# Keywords¶

## Links to manual entries¶

**ams:**

**band:**

## Summary of all keywords¶

### Engine Band¶

`AIMCriticalPoints`

- Type
Block

- Description
Compute the critical points of the density (Atoms In Molecules). The algorithm starts from a regular mesh of points, and from each of these it walks towards its corresponding critical point.

`Enabled`

- Type
Bool

- Default value
No

- GUI name
: Critical points and bond paths

- Description
Compute the critical points of the density (Atoms In Molecules). The algorithm starts from a regular mesh of points, and from each of these it walks towards its corresponding critical point.

`EqvPointsTol`

- Type
Float

- Default value
0.27

- Unit
Bohr

- Description
If the distance between two critical points is smaller than this value, the two critical points are considered to be the same point.

`GridPadding`

- Type
Float

- Default value
0.7

- Unit
Bohr

- Description
How much extra space is added to the starting guess domain in the search for the critical points

`GridSpacing`

- Type
Float

- Default value
0.5

- Unit
Bohr

- Description
The distance between the initial trial points.

`Allow`

- Type
String

- Recurring
True

- Description
Debugging feature to let the program continue even when intermediate results seem to be wrong or very inaccurate

`ATensor`

- Type
Block

- Description
Hyperfine A-tensor.

`Enabled`

- Type
Bool

- Default value
No

- GUI name
:A-tensor

- Description
Compute the hyperfine A-tensor. Note: Unrestricted calculation is required.

`AtomType`

- Type
Block

- Recurring
True

- Description
Explicit basis set definition for given atom type.

`AutomaticGaussians`

- Type
Non-standard block

- Description
Definition of the automatic gaussians

`BasisFunctions`

- Type
Non-standard block

- Description
Definition of the extra Slater-type orbitals

`ContractedGaussians`

- Type
Non-standard block

- Description
Definition of the contracted gaussians

`Dirac`

- Type
Non-standard block

- Description
Specification of the numerical (‘Herman-Skillman’) free atom, which defines the initial guess for the SCF density, and which also (optionally) supplies Numerical Atomic Orbitals (NOs) as basis functions

`FitFunctions`

- Type
Non-standard block

- Description
Slater-type fit functions. Obsolete feature.

`BandStructure`

- Type
Block

- Description
Options for the calculation of the band structure.

`Automatic`

- Type
Bool

- Default value
Yes

- GUI name
Automatic generate path

- Description
If True, BAND will automatically generate the standard path through the Brillouin zone. If False BAND will use the user-defined path in BZPath.

`DeltaK`

- Type
Float

- Default value
0.1

- Unit
1/Bohr

- GUI name
Interpolation delta-K

- Description
Step (in reciprocal space) for band structure interpolation. Using a smaller number (e.g. 0.03) will result in smoother band curves at the cost of an increased computation time.

`Enabled`

- Type
Bool

- Default value
No

- GUI name
Calculate band structure

- Description
If True, Band will calculate the band structure and save it to file for visualization.

`EnergyAboveFermi`

- Type
Float

- Default value
0.75

- Unit
Hartree

- GUI name
Energy above Fermi level

- Description
Bands with minimum energy larger then FermiEnergy + EnergyAboveFermi are not saved to file. Increasing the value of EnergyAboveFermi will result in more unoccupied bands to be saved to file for visualization.

`EnergyBelowFermi`

- Type
Float

- Default value
10.0

- Unit
Hartree

- GUI name
Energy below Fermi level

- Description
Bands with maximum energy smaller then FermiEnergy - EnergyBelowFermi are not saved to file. Increasing the value of EnergyBelowFermi will result in more occupied core bands to be saved to file for visualization. Note: EnergyBelowFermi should be a positive number!

`FatBands`

- Type
Bool

- Default value
Yes

- GUI name
Calculate fatbands

- Description
If True, BAND will compute the fat bands (only if BandStructure%Enabled is True). The Fat Bands are the periodic equivalent of the Mulliken population analysis.

`UseSymmetry`

- Type
Bool

- Default value
Yes

- GUI name
Use symmetry

- Description
If True, only the irreducible wedge of the Wigner-Seitz cell is sampled. If False, the whole (inversion-unique) Wigner-Seitz cell is sampled. Note: The Symmetry key does not influence the symmetry of the band structure sampling.

`Basis`

- Type
Block

- Description
Definition of the basis set

`Core`

- Type
Multiple Choice

- Default value
Large

- Options
[None, Small, Medium, Large]

- GUI name
Frozen core

- Description
Select the size of the frozen core you want to use. Small, Medium, and Large will be interpreted within the basis sets available (of the selected quality), and might refer to the same core in some cases.

`Folder`

- Type
String

- Description
Path to a folder containing the basis set files. This can be used for special use-defined basis sets. Cannot be used in combination with ‘Type’

`PerAtomType`

- Type
Block

- Recurring
True

- Description
Defines the basis set for all atoms of a particular type.

`Core`

- Type
Multiple Choice

- Options
[None, Small, Medium, Large]

- Description
Size of the frozen core.

`File`

- Type
String

- Description
The path to the basis set file. The path can be absolute or relative to $AMSRESOURCES/Band. Specifying the path to the basis file explicitly overrides the automatic basis file selection via the Type and Core subkeys.

`Symbol`

- Type
String

- Description
The symbol for which to define the basis set.

`Type`

- Type
Multiple Choice

- Options
[SZ, DZ, DZP, TZP, TZ2P, QZ4P]

- Description
The basis sets to be used.

`PerRegion`

- Type
Block

- Recurring
True

- Description
Defines the basis set for all atoms in a region. If specified, this overwrites the values set with the Basis%Type and Basis%PerAtomType keywords for atoms in that region. Note that if this keyword is used multiple times, the chosen regions may not overlap.

`Core`

- Type
Multiple Choice

- Default value
Large

- Options
[None, Small, Medium, Large]

- Description
Size of the frozen core.

`Region`

- Type
String

- Description
The identifier of the region for which to define the basis set. Note that this may also be a region expression, e.g. ‘myregion+myotherregion’ (the union of two regions).

`Type`

- Type
Multiple Choice

- Default value
DZ

- Options
[SZ, DZ, DZP, TZP, TZ2P, QZ4P]

- Description
The basis sets to be used.

`Type`

- Type
Multiple Choice

- Default value
DZ

- Options
[SZ, DZ, DZP, TZP, TZ2P, QZ4P, STO/TZ2P, STO/SZ, STO/DZ, STO/DZP, STO/QZ4P, CORR/QZ6P, CORR/TZ3P, GTO/CC-PV5Z, GTO/DEF2-QZVPPD, GTO/CC-PV6Z, GTO/CC-PVQZ, GTO/CC-PVTZ, GTO/CC-PVDZ, GTO/DEF2-SVP, GTO/DEF2-TZVP, GTO/DEF2-TZVPP, GTO/DEF2-QZVP, GTO/AUG-CC-PVDZ, GTO/AUG-CC-PVTZ]

- GUI name
Basis set

- Description
Select the basis set to use. SZ : Single Z DZ : Double Z DZP : Double Z, 1 polarization function TZP : Triple Z, 1 polarization function TZ2P : Triple Z, 2 polarization functions QZ4P : Quadruple Z, 4 polarization function The basis set chosen will apply to all atoms in your structure. If a matching basis is not found a better type might be used.

`BeckeGrid`

- Type
Block

- Description
Options for the numerical integration grid, which is a refined version of the fuzzy cells integration scheme developed by Becke.

`Quality`

- Type
Multiple Choice

- Default value
Auto

- Options
[Auto, Basic, Normal, Good, VeryGood, Excellent]

- Description
Quality of the integration grid. For a description of the various qualities and the associated numerical accuracy see reference. If ‘Auto’, the quality defined in the ‘NumericalQuality’ will be used.

`QualityPerRegion`

- Type
Block

- Recurring
True

- Description
Sets the grid quality for all atoms in a region. If specified, this overwrites the globally set quality.

`Quality`

- Type
Multiple Choice

- Options
[Basic, Normal, Good, VeryGood, Excellent]

- Description
The region’s integration grid quality.

`Region`

- Type
String

- Description
The identifier of the region for which to set the quality.

`RadialGridBoost`

- Type
Float

- Default value
1.0

- Description
The number of radial grid points will be boosted by this factor. Some XC functionals require very accurate radial integration grids, so BAND will automatically boost the radial grid by a factor 3 for the following numerically sensitive functionals: LibXC M05, LibXC M05-2X, LibXC M06-2X, LibXC M06-HF, LibXC M06-L, LibXC M08-HX, LibXC M08-SO, LibXC M11-L, LibXC MS0, LibXC MS1, LibXC MS2, LibXC MS2H, LibXC MVS, LibXC MVSH, LibXC N12, LibXC N12-SX, LibXC SOGGA11, LibXC SOGGA11-X, LibXC TH1, LibXC TH2, LibXC WB97, LibXC WB97X, MetaGGA M06L, MetaHybrid M06-2X, MetaHybrid M06-HF, MetaGGA MVS.

`BerryPhase`

- Type
Bool

- Default value
No

- Description
Boolean that determines whether the dipole as determined through the Berry phase approach should be calculated.

`BField`

- Type
Block

- Description
The effect of a magnetic filed can be approximated by the following potential: mu * sigma_i * B, where mu is the Bohr magneton, sigma_i are the Pauli matrices and B is the magnetic field

`Bx`

- Type
Float

- Default value
0.0

- Unit
Tesla

- Description
Value of the x component of the BField

`By`

- Type
Float

- Default value
0.0

- Unit
Tesla

- Description
Value of the y component of the BField

`Bz`

- Type
Float

- Default value
0.0

- Unit
Tesla

- Description
Value of the z component of the BField

`Dipole`

- Type
Bool

- Default value
No

- GUI name
Bfield is: Atomic dipole

- Description
Use an atomic dipole as magnetic field instead of a uniform magnetic field.

`DipoleAtom`

- Type
Integer

- Default value
1

- GUI name
on atom number

- Description
Atom on which the magnetic dipole should be centered (if using the dipole option)

`Method`

- Type
Multiple Choice

- Default value
NR_SDOTB

- Options
[NR_SDOTB, NR_LDOTB, NR_SDOTB_LDOTB]

- Description
There are two terms coupling to an external magnetic field. One is the intrinsic spin of the electron, called S-dot-B, the other one is the orbital momentum call L-dot-B. The L.B is implemented non-relativistically, using GIAOs in the case of a homogeneous magnetic field (not for the dipole case).

`Unit`

- Type
Multiple Choice

- Default value
tesla

- Options
[tesla, a.u.]

- Description
Unit of magnetic filed. The a.u. is the SI version of a.u.

`BZPath`

- Type
Block

- Description
Definition of the user-defined path in the Brillouin zone for band structure plotting.

`path`

- Type
Non-standard block

- Recurring
True

- Description
Definition of the k-points in a path. The vertices of your path should be defined in fractional coordinates (wrt the reciprocal lattice vectors)

`Comment`

- Type
Non-standard block

- Description
The content of this block will be copied to the output header as a comment to the calculation.

`Convergence`

- Type
Block

- Description
Options and parameters related to the convergence behavior of the SCF procedure.

`Criterion`

- Type
Float

- Description
Criterion for termination of the SCF procedure. The default depends on the NumericalQuality and on the number of atoms in the system. Can be used for EngineAutomations

`CriterionFactor`

- Type
Float

- Default value
1.0

- Description
Multiply Criterion (which depends on system and quality) with this factor. Can be used for EngineAutomations

`Degenerate`

- Type
String

- Default value
default

- Description
Smooths (slightly) occupation numbers around the Fermi level, so as to insure that nearly-degenerate states get (nearly-) identical occupations. Be aware: In case of problematic SCF convergence the program will turn this key on automatically, unless the key ‘Nodegenerate’ is set in input. The smoothing depends on the argument to this key, which can be considered a ‘degeneration width’. When the argument reads default, the program will use the value 1e-4 a.u. for the energy width.

`ElectronicTemperature`

- Type
Float

- Default value
0.0

- Unit
Hartree

- Description
(KT) Specify this key for a gradient independent electronic temperature

`InitialDensity`

- Type
Multiple Choice

- Default value
rho

- Options
[rho, psi, frompot]

- Description
The SCF is started with a guess of the density. There are the following choices RHO: the sum of atomic density. PSI: construct an initial eigensystem by occupying the atomic orbitals. The guessed eigensystem is orthonormalized, and from this the density is calculated/

`LessDegenerate`

- Type
Bool

- Default value
No

- Description
If smoothing of occupations over nearly degenerate orbitals is applied (see Degenerate key), then, if this key is set in the input file, the program will limit the smoothing energy range to 1e-4 a.u. as soon as the SCF has converged ‘halfway’, i.e. when the SCF error has decreased to the square root of its convergence criterion.

`ModestCriterion`

- Type
Float

- Default value
-1.0

- Description
If this is specified band will consider the SCF converged if the error is below this criterion (after using the maximum number of iterations).

`NoDegenerate`

- Type
Bool

- Default value
No

- Description
This key prevents any internal automatic setting of the key DEGENERATE.

`NumBoltz`

- Type
Integer

- Default value
10

- Description
The electronic temperature is done with a Riemann Stieltjes numerical integration, between zero and one occupation. This defines the number of points to be used.

`SpinFlip`

- Type
Integer List

- GUI name
Flip spin for atoms

- Description
List here the atoms for which you want the initial spin polarization to be flipped. This way you can distinguish between ferromagnetic and anti ferromagnetic states. Currently, it is not allowed to give symmetry equivalent atoms a different spin orientation. To achieve that you have to break the symmetry.

`SpinFlipEnabled`

- Type
Bool

- Default value
Yes

- Description
If set to False, the keys SpinFlip and SpinFlipRegion are ignored. Only useful/convenient when trying to compare in a script the effect of spin flip.

`SpinFlipRegion`

- Type
String

- Recurring
True

- GUI name
Flip spin for region

- Description
Specify here the region for which you want the initial spin polarization to be flipped. This way you can distinguish between ferromagnetic and anti ferromagnetic states. Currently, it is not allowed to give symmetry equivalent atoms a different spin orientation. To achieve that you have to break the symmetry.

`StartWithMaxSpin`

- Type
Bool

- Default value
Yes

- Description
To break the initial perfect symmetry of up and down densities there are two strategies. One is to occupy the numerical orbitals in a maximum spin configuration. The alternative is to add a constant to the potential. See also Vsplit key.

`StartWithMaxSpinForSO`

- Type
Bool

- Default value
No

- Description
Same as the StartWithMaxSpin option. In case of spin-orbit band always used to split the potential. Now will use maxspin in case of SpinFlip. With this option it will always do that.

`CPVector`

- Type
Integer

- Default value
128

- GUI name
Vectorlength (blocksize)

- Description
The code is vectorized and this key can be used to set the vector length

`DensityPlot`

- Type
Non-standard block

- Description
Plots of the density. Goes together with the Restart%DensityPlot and Grid keys.

`Dependency`

- Type
Block

- Description
Criteria for linear dependency of the basis and fit set

`AllowBasisDependency`

- Type
Bool

- Default value
Yes

- Description
Project out the dependent part of the basis set (associated with small eigenvalues of the overlap matrix).

`Basis`

- Type
Float

- Default value
1e-08

- GUI name
Dependency criterion

- Description
Criteria for linear dependency of the basis: smallest eigenvalue of the overlap matrix of normalized Bloch functions.

`Core`

- Type
Float

- Default value
0.8

- Description
The program verifies that the frozen core approximation is reasonable, by checking the smallest eigen value of the overlap matrix of the core (Bloch) orbitals (which should ideally be one) is bigger than this criterion.

`CoreValence`

- Type
Float

- Default value
1e-05

- Description
Criterion for dependency of the core functions on the valence basis. The maximum overlap between any two normalized functions in the two respective function spaces should not exceed 1.0-corevalence

`Fit`

- Type
Float

- Default value
5e-06

- Description
Criterion for dependency of the total set of fit functions. The value monitored is the smallest eigenvalue of the overlap matrix of normalized Bloch sums of symmetrized fit functions.

`DIIS`

- Type
Block

- Description
Parameters for the DIIS procedure to obtain the SCF solution

`Adaptable`

- Type
Bool

- Default value
Yes

- Description
Change automatically the value of dimix during the SCF.

`CHuge`

- Type
Float

- Default value
20.0

- GUI name
No DIIS (but damping) when coefs >

- Description
When the largest coefficient in the DIIS expansion exceeds this value, damping is applied

`CLarge`

- Type
Float

- Default value
20.0

- GUI name
Reduce DIIS space when coefs >

- Description
When the largest DIIS coefficient exceeds this value, the oldest DIIS vector is removed and the procedure re-applied

`Condition`

- Type
Float

- Default value
1000000.0

- Description
The condition number of the DIIS matrix, the largest eigenvalue divided by the smallest, must not exceed this value. If this value is exceeded, this vector will be removed.

`DiMix`

- Type
Float

- Default value
0.2

- GUI name
Bias DIIS towards latest vector with

- Description
Mixing parameter for the DIIS procedure

`DiMixMax`

- Type
Float

- Default value
-1.0

- Description
For adaptive diis: A negative value means automatic, see DiMixatnvctrx. If positive it is an absolute upper bound for (adaptive) dimix

`DiMixMin`

- Type
Float

- Default value
0.01

- Description
An absolute lower bound for adaptive dimix.

`NCycleDamp`

- Type
Integer

- Default value
1

- GUI name
Do not start DIIS before cycle

- Description
Number of initial iterations where damping is applied, before any DIIS is considered

`NVctrx`

- Type
Integer

- Default value
20

- GUI name
Size of DIIS space

- Description
Maximum number of DIIS expansion vectors

`Variant`

- Type
Multiple Choice

- Default value
DIIS

- Options
[DIIS, LISTi, LISTb, LISTd]

- Description
Which variant to use. In case of problematic SCF convergence, first try MultiSecant, and if that does not work the LISTi is the advised method. Note: LIST is computationally more expensive per SCF iteration than DIIS.

`DOS`

- Type
Block

- Description
Density-Of-States (DOS) options

`CalcDOS`

- Type
Bool

- Default value
Yes

- GUI name
Calculate DOS

- Description
Whether or not to calculate the density of states.

`CalcPDOS`

- Type
Bool

- Default value
No

- GUI name
Calculate PDOS

- Description
Whether or not to calculate the partial DOS (projections on basis functions). This can be significantly more expensive than calculating the total DOS

`CalcPopulationAnalysis`

- Type
Bool

- Default value
Yes

- GUI name
Calculate Mulliken charges

- Description
Whether or not to calculate the population analysis. Population analysis can become very expensive when there are many symmetry operators, such as in a super cell.

`CompensateDeltaE`

- Type
Bool

- Default value
Yes

- Description
Only relevant when IntegrateDeltaE=yes. If set to true then after integrating each interval over DeltaE the result is divided by DeltaE, so that the unit is DOS.

`DeltaE`

- Type
Float

- Default value
0.005

- Unit
Hartree

- GUI name
Delta E

- Description
Energy step for the DOS grid. Using a smaller value (e.g. half the default value) will result in a finer sampling of the DOS.

`Energies`

- Type
Integer

- Description
Number of equidistant energy-values for the DOS grid. This keyword is superseded by the ‘DeltaE’ keyword.

`File`

- Type
String

- Description
Write the DOS (plain text format) to the specified file instead of writing it to the standard output.

`IntegrateDeltaE`

- Type
Bool

- Default value
Yes

- Description
This subkey handles which algorithm is used to calculate the data-points in the plotted DOS. If true, the data-points represent an integral over the states in an energy interval. Here, the energy interval depends on the number of Energies and the user-defined upper and lower energy for the calculation of the DOS. The result has as unit [number of states / (energy interval * unit cell)]. If false, the data-points do represent the number of states for a specific energy and the resulting plot is equal to the DOS per unit cell (unit: [1/energy]). Since the resulting plot can be a wild function and one might miss features of the DOS due to the step length between the energies, the default is set to the integration algorithm.

`Max`

- Type
Float

- Unit
Hartree

- Description
User defined upper bound energy (with respect to the Fermi energy)

`Min`

- Type
Float

- Unit
Hartree

- Description
User defined lower bound energy (with respect to the Fermi energy)

`StoreCoopPerBasPair`

- Type
Bool

- Default value
No

- GUI name
Calculate COOP

- Description
Calculate the COOP (crystal orbital overlap population).

`DosBas`

- Type
Non-standard block

- Description
Used to specify the fragment basis for the DOS.

`DumpBasisOnly`

- Type
Bool

- Default value
No

- Description
Dump basis and fit set files use for each atom.

`EffectiveMass`

- Type
Block

- Description
In a semi-conductor, the mobility of electrons and holes is related to the curvature of the bands at the top of the valence band and the bottom of the conduction band. With the effective mass option, this curvature is obtained by numerical differentiation. The estimation is done with the specified step size, and twice the specified step size, and both results are printed to give a hint on the accuracy. The easiest way to use this key is to enabled it without specifying any extra options.

`Enabled`

- Type
Bool

- Default value
No

- GUI name
Effective mass

- Description
Compute the EffectiveMass.

`KPointCoord`

- Type
Float List

- Unit
1/Bohr

- Recurring
True

- GUI name
At K-point

- Description
Coordinate of the k-points for which you would like to compute the effective mass.

`NumAbove`

- Type
Integer

- Default value
1

- GUI name
Include N bands above

- Description
Number of bands to take into account above the Fermi level.

`NumBelow`

- Type
Integer

- Default value
1

- GUI name
Include N bands below

- Description
Number of bands to take into account below the Fermi level.

`StepSize`

- Type
Float

- Default value
0.001

- Description
Size of the step taken in reciprocal space to perform the numerical differentiation

`EFG`

- Type
Block

- Description
The electronic charge density causes an electric field, and the gradient of this field couples with the nuclear quadrupole moment, that some (non-spherical) nuclei have and can be measured by several spectroscopic techniques. The EFG tensor is the second derivative of the Coulomb potential at the nuclei. For each atom it is a 3x3 symmetric and traceless matrix. Diagonalization of this matrix gives three eigenvalues, which are usually ordered by their decreasing absolute size and denoted as V_{xx}, V_{yy}, V_{zz}. The result is summarized by the largest eigenvalue and the asymmetry parameter.

`Enabled`

- Type
Bool

- Default value
No

- GUI name
EFG (electric field gradient): Calculate

- Description
Compute the EFG tensor (for nuclear quadrupole interaction).

`EigThreshold`

- Type
Float

- Default value
0.01

- Description
Threshold for printing the eigenvectors coefficients (Print Eigens)

`ElectronHole`

- Type
Block

- Description
Allows one to specify an occupied band which shall be depopulated, where the electrons are then moved to the Fermi level. For a spin-restricted calculation 2 electrons are shifted and for a spin-unrestricted calculation only one electron is shifted.

`BandIndex`

- Type
Integer

- Description
Which occupied band shall be depopulated.

`SpinIndex`

- Type
Integer

- Description
Defines the spin of the shifted electron (1 or 2).

`EmbeddingPotential`

- Type
Block

- Description
An external potential can be read in and will be added to the effective Kohn-Sham potential. It has to be on the becke grid

`Filename`

- Type
String

- Default value
- Description
Name of the file containing the embedding potential.

`PotentialName`

- Type
String

- Default value
- Description
Name of variable containing the potential.

`EnforcedSpinPolarization`

- Type
Float

- GUI name
Spin polarization

- Description
Enforce a specific spin-polarization instead of occupying according to the aufbau principle. The spin-polarization is the difference between the number of alpha and beta electron. Thus, a value of 1 means that there is one more alpha electron than beta electrons. The number may be anything, including zero, which may be of interest when searching for a spin-flipped pair, that may otherwise end up in the (more stable) parallel solution.

`ESR`

- Type
Block

- Description
Zeeman g-tensor. The Zeeman g-tensor is implemented using two-component approach of Van Lenthe and co-workers in which the g-tensor is computed from a pair of spinors related to each other by time-reversal symmetry. Note: the following options are necessary for ESR: ‘Relativistic zora spin’ and ‘Kspace 1’

`Enabled`

- Type
Bool

- Default value
No

- GUI name
ESR: g-tensor

- Description
Compute Zeeman g-tensor. The Zeeman g-tensor is implemented using two-component approach of Van Lenthe and co-workers in which the g-tensor is computed from a pair of spinors related to each other by time-reversal symmetry. Note: the following options are necessary for ESR: ‘Relativistic zora spin’ and ‘Kspace 1’

`Excitations`

- Type
Block

- Description
Excitation energies: UV/Vis

`Fermi`

- Type
Block

- Description
Technical parameter used in determining the Fermi energy, which is carried out at each cycle of the SCF procedure.

`Delta`

- Type
Float

- Default value
0.0001

- Description
Convergence criterion: upper and lower bounds for the Fermi energy and the corresponding integrated charge volumes must be equal within delta.

`Eps`

- Type
Float

- Default value
1e-10

- Description
After convergence of the Fermi energy search procedure, a final estimate is defined by interpolation and the corresponding integrated charge volume is tested. It should be exact, to machine precision. Tested is that it deviates not more than eps.

`MaxTry`

- Type
Integer

- Default value
15

- Description
Maximum number of attempts to locate the Fermi energy. The procedure is iterative in nature, narrowing the energy band in which the Fermi energy must lie, between an upper and a lower bound. If the procedure has not converged sufficiently within MaxTry iterations, the program takes a reasonable value and constructs the charge density by interpolation between the functions corresponding to the last used upper and lower bounds for the Fermi energy.

`RefinePostSCFFactor`

- Type
Integer

- Description
Use a finer k-grid after the scf to calculate a refined fermi level. Makes only sense for metals. Works like DoubleCount. Use 1,2,3

`FermiSurface`

- Type
Block

- Description
Calculation of the Fermi surface for metals

`Enabled`

- Type
Bool

- Default value
No

- GUI name
Calculate Fermi surface

- Description
Calculate the Fermi surface if the system has no band gap (i.e. is a metal). The result can be visualized with amsbands.

`KIntegForSymmetricKGrid`

- Type
Integer

- Default value
-1

- Description
If the (default) regular k-grid is used, a symmetric one is created to determine the Fermi surface. If this key is not specified an automatic value of kInteg is used. Odd values trigger quadratic interpolation.

`NMesh`

- Type
Integer

- Default value
7

- Description
Improves the matching of the interpolated quadratic surface. For better results it makes more sense to increases KIntegForSymmetricKGrid.

`FormFactors`

- Type
Integer

- Default value
2

- Description
Number of stars of K-vectors for which the form factors are computed

`Fragment`

- Type
Block

- Recurring
True

- Description
Defines a fragment. You can define several fragments for a calculation.

`AtomMapping`

- Type
Non-standard block

- Description
Format ‘indexFragAt indexCurrentAt’. One has to associate the atoms of the fragment to the atoms of the current calculation. So, for each atom of the fragment the indexFragAt has to be associated uniquely to the indexCurrentAt for the current calculation.

`Filename`

- Type
String

- Description
Filename of the fragment. Absolute path or path relative to the executing directory.

`Labels`

- Type
Non-standard block

- Description
This gives the possibility to introduce labels for the fragment orbitals. See examples.

`FuzzyPotential`

- Type
Non-standard block

- Description
Atomic (fuzzy cell) based, external, electric potential. See example.

`FuzzyUnitCellGrid`

- Type
Block

- Description
Undocumented.

`AtomRadiusLSG`

- Type
Float

- Default value
0.0

- Description
Undocumented.

`CellPartitionDelta`

- Type
Float

- Default value
4.0

- Description
Undocumented.

`CellPartitionInterpolationCubic`

- Type
Bool

- Default value
No

- Description
Undocumented.

`CellPartitionInterpolationMesh`

- Type
Integer

- Default value
100

- Description
Undocumented.

`CellPartitionVersion`

- Type
Integer

- Default value
2

- Description
Undocumented.

`CentralizeNaturalLSG`

- Type
Bool

- Default value
No

- Description
Undocumented.

`InterpolateCellPartition`

- Type
Bool

- Default value
No

- Description
Undocumented.

`NumIntExtraL`

- Type
Integer

- Default value
0

- Description
Undocumented.

`NumIntExtraRad`

- Type
Integer

- Default value
0

- Description
Undocumented.

`PartitionFunctionTol`

- Type
Float

- Default value
1e-08

- Description
Undocumented.

`PruneLatticeSummedGrid`

- Type
Bool

- Default value
Yes

- Description
Undocumented.

`ReduceAccuracyLSG`

- Type
Bool

- Default value
No

- Description
Undocumented.

`SimpleLatticeSummedGrid`

- Type
Bool

- Default value
No

- Description
Undocumented.

`Grid`

- Type
Block

- Description
Options for the regular grid used for plotting (e.g. density plot). Used ICW the restart option.

`ExtendX`

- Type
Float

- Default value
0.0

- Unit
Bohr

- Description
Extend the default regular grid along the x-direction by the specified amount: [x_min, x_max] => [x_min - ExtendX/2, x_max + ExtendX/2].

`ExtendY`

- Type
Float

- Default value
0.0

- Unit
Bohr

- Description
Extend the default regular grid along the y-direction by the specified amount: [y_min, y_max] => [y_min - ExtendY/2, y_max + ExtendY/2].

`ExtendZ`

- Type
Float

- Default value
0.0

- Unit
Bohr

- Description
Extend the default regular grid along the z-direction by the specified amount: [z_min, z_max] => [z_min - ExtendZ/2, z_max + ExtendZ/2].

`FileName`

- Type
String

- Default value
- Description
Read in the grid from a file. The file format of the grid is: three numbers per line (defining the x, y and z coordinates of the points).

`Type`

- Type
Multiple Choice

- Default value
coarse

- Options
[coarse, medium, fine]

- Description
The default regular grids.

`UserDefined`

- Type
Non-standard block

- Description
One can define the regular grid specification in this block. See example. Default unit is Bohr

`GridBasedAIM`

- Type
Block

- Description
Invoke the ultra fast grid based Bader analysis.

`Enabled`

- Type
Bool

- Default value
No

- GUI name
Bader (AIM): Atomic properties

- Description
Invoke the ultra fast grid based Bader analysis.

`Iterations`

- Type
Integer

- Default value
40

- Description
The maximum number of steps that may be taken to find the nuclear attractor for a grid point.

`SmallDensity`

- Type
Float

- Default value
1e-06

- Description
Value below which the density is ignored. This should not be chosen too small because it may lead to unassignable grid points.

`UseStartDensity`

- Type
Bool

- Default value
No

- Description
Whether the analysis is performed on the startup density (True) or on the final density (False).

`GrossPopulations`

- Type
Non-standard block

- Description
Partial DOS (pDOS) are generated for the gross populations listed under this key. See example.

`GW`

- Type
Block

- Description
Instruct ADF to perform a G0W0 calculation.

`AdaptiveMixing`

- Type
Float List

- Description
Requests to use adaptive mixing instead of DIIS and sets the staring mixing parameter for mixing of Green’s function in case of self-consistency. Adapative mixing is recommended in case a qsGW calculation does not converge with DIIS. It is ignored in non-selfconsistent calculation and overwritten by DIIS when DIIS is also present.

`AnalyticalIntegration`

- Type
Block

- Description
Use analytical integration to calculate the self-energy. Very slow, unless the system is very small but useful to check the accuracy of the frequency integration

`Enabled`

- Type
Bool

- Default value
No

- GUI name
analytical integration

- Description
Enable the calculation of the GW quasi-particle energies via analytical integration.

`Polarizability`

- Type
Multiple Choice

- Default value
RPA

- Options
[RPA, BSE]

- Description
Sets the expression for the Polarizability used in the GW calculation. RPA is the Default and amounts to a standard GW calculation. BSE denotes screening in the Bethe-Salpeter-equation formalism.

`PrintSpectralFunction`

- Type
Bool

- Default value
No

- Description
Plot the self-energy as a function of frequency. Automatically done in case of analytical continuation. However, this is expensive in the analytical integration formalism.

`SpectralFunctionResolution`

- Type
Integer

- Default value
800

- Description
Number of points at which spectral function is evaluated.

`TDA`

- Type
Bool

- Default value
No

- Description
Solve the linear response equations in the Tamm-Dancoff approximation.

`eta`

- Type
Float

- Default value
0.001

- Description
Artificial (positive) broadening parameter for evaluation of self-energy in analytical integration. Ideally should be as small as possible but this might lead to convergence issues in partially self-consistent approaches. In this case, a value of up to 0.1 is possible.

`Converge`

- Type
Block

- Description
Sets convergence criteria for the GW calculation in self-consistent case

`Density`

- Type
Float List

- Default value
[1e-08, 1e-05]

- Description
First Criterion for self-consistency procedure to terminate. Criterion is the trace of the density matrix. Ignored in non-selfconsistent Calculation and in eigenvalue self-consistent GW It is possible to run a qsGW calculation with an inner SCF loop which updates the static part of the elf-energy only. This can be useful to accelerate the convergence in case linear mixing is used. It is not recommended to use linear mixing, so it is also not recommended to use that inner loop as well. The second number in this list specifies the convergence criterion for the inner SCF loop.

`HOMO`

- Type
Float

- Default value
0.003

- Unit
eV

- GUI name
HOMO energy convergence

- Description
Criterion for self-consistency procedure to terminate. The self-consistent GW calculation terminates, when the difference between the HOMO QP energies between 2 consecutive iterations is below this number. The LUMO energy converged faster than the HOMO energy so when the HOMO energy is converged according to this criterion, the LUMO energy will be converged as well. In non-selfconsistent Calculation, this criterion is ignored.

`DIIS`

- Type
Integer

- Default value
10

- Description
Requests to use DIIS. This is the Default. Number of expansion coefficients can be requested as well. Ignored in non-selfconsistent calculation

`Enabled`

- Type
Bool

- Default value
No

- GUI name
Calculate GW quasi-particle energies

- Description
Enable the calculation of the GW quasi-particle energies.

`FixedGrids`

- Type
Bool

- Default value
No

- Description
In a self-consistent GW calculation, do not recalculate Grids. Can be useful in case of convergence problems. Only relevant for qsGW and qsGW0. In case of evGW and evGW0, the grids are always kept fixed.

`LinearMixing`

- Type
Float List

- Description
Requests to use linear mixing instead of DIIS and sets the mixing parameter for linear mixing of Green’s function in case of self-consistency. It is ignored in non-selfconsistent calculation and overwritten by DIIS when DIIS is also present.

`LinearizeQPequations`

- Type
Bool

- Default value
No

- Description
Instead of solving the non-linear QP equations in a G0W0 (or evGW calculation) by bisection exactly, linearize them by first-order Taylor expansion. This is not recommended since it does not save computational time when used together with analytical continuation (as implemented in AMS). It might however be useful for benchmarking or for validating results. If the results os the linearization differ by a lot (for instance, more than 0.1 eV in frontier QP energies) from the non-linearized results, this might indicate that the GW calculation is not reliable.

`OffDiagonalEFermi`

- Type
Bool

- Default value
No

- Description
Analytically continue the off-diagonal elements of the KSF2 qsGW Hamiltonian at the Fermi-energy instead of omega=0. Typically leads to slightly lower QP energies, i.e. higher ionization potentials. The HOMO-LUMO gaps are typically not affected.

`PrintAllSolutions`

- Type
Bool

- Default value
No

- Description
Print out all solutions for all requested states. Detects multiple solutions of the QP equations.

`QPHamiltonian`

- Type
Multiple Choice

- Default value
KSF2

- Options
[KSF1, KSF2, SRG, LQSGW]

- Description
The quasi-particle Hamiltonian can be constructed in different ways. KSF1 refers to the original construction by Kotani, Van Schilfgaarde anf Faleev (KSF) which is also implemented in TURBOMOLE. KSF2 refers to an alternative construction by KSF. KSF1 is not recommended since it is numerically less stable than KSF2. The results are typically very similar. The QP energies at which the matrix elements are evaluated can be tweaked further, see the two subsequent keys: However, KSF2 is recommended since it typically leads to QP energies with the best agreement with experiment. Ignored when not a quasi-particle self-consistent GW calculation is performed

`ScissorShift`

- Type
Bool

- Default value
No

- Description
Only calculate the HOMO and LUMO QP energies and shift the remaining QP energies by the same amount. This is a rather crude approximation and not recommended. It might again be useful for benchmarking purposes.

`SelfConsistency`

- Type
Multiple Choice

- Default value
G0W0

- Options
[G0W0, EVGW0, EVGW, QSGW0, QSGW]

- Description
Sets the level of self-consistency in a GW calculation. G0W0 calculates a one-shot, perturbative correction to the KS eigenvalues. In evGW and evGW0, the quasi-particle energies are updated until self-consistency is reached. evGW0 requests that the Green’s function is evaluated self-consistently but not the screened interaction. In qsGW, the density is updated as well, however, the self-energy is mapped to a static effective potential and the Dyson equation is solved by diagonalization instead of inversion. The results of a qsGW are independent of the choice of the underlying exchange-correlation functional and are usually the most accurate ones. The same is done in qsGW0, but the screened interaction is not updated.

`SelfEnergy`

- Type
Multiple Choice

- Default value
GW

- Options
[HF, GW, G3W2, SOSEX, GWGamma, G3W2dynamic]

- Description
Controls the form of the self-energy. GW is the default and corresponds to the standard GW calculation. G3W2 is a GW calculation plus a perturbative second-order statically screened exchange correction (second order expansion in the self-energy). Note, that there the self-energy is always static.

`nIterations`

- Type
Integer List

- Default value
[10]

- GUI name
Number of iterations

- Description
The maximum number of iterations within the (partially or fully) self-consistent GW calculation has to converge. Ignored when Formalism is set to G0W0

`nLowest`

- Type
Integer

- Default value
1

- GUI name
N Lowest

- Description
Number of lowest occupied QP levels to be evaluated, overwrites nStates’

`nStates`

- Type
Integer

- Default value
5

- GUI name
N states

- Description
Number of Quasiparticle States to be printed to output. The default is 5 states which in this case means that min(5, Number of particle states) occupied and min(5, Number of hole states) hole states are printed. The whole list of states can be printed by setting this parameter to -1’

`preconditionQSGW`

- Type
Bool

- Default value
No

- Description
If true, the QSGW equations are solved but prior to each diagonalization, i.e. a G0W0 calculation is performed to find the optimal QP energies at which to analytically continue the self-energy. This is in principle a more consistent construction than KSF1 or KSF2 since the diagonal elements are consistent with G0W0. In KSF1 and KSF2, the diagonal elements are evaluated at the QP energies from the previous iteration which is equivalent to a zeroth-order Taylor expansion of the diagonal elements around the previous QP energies.Enabling this option typically leads to slightly lower QP energies.

`HubbardU`

- Type
Block

- Description
Options for Hubbard-corrected DFT calculations.

`Atom`

- Type
Block

- Recurring
True

- Description
Specify Hubbard parameters (U,l) for a certain element

`Element`

- Type
String

- Description
Name of the element, such as Cu or Zn

`LValue`

- Type
Multiple Choice

- Default value
s

- Options
[s, p, d, f]

- Description
L value of the shell to apply the Hubbard model to

`UValue`

- Type
Float

- Default value
0.0

- Unit
Hartree

- Description
Hubbard U value.

`PrintOccupations`

- Type
Bool

- Default value
Yes

- Description
Whether or not to print the occupations during the SCF.

`Region`

- Type
Block

- Recurring
True

- Description
Specify Hubbard parameters (U,l) for all atoms in a certain region

`LValue`

- Type
Multiple Choice

- Default value
s

- Options
[s, p, d, f]

- Description
L value of the shell to apply the Hubbard model to

`Name`

- Type
String

- Description
Name of the region

`UValue`

- Type
Float

- Default value
0.0

- Unit
Hartree

- Description
Hubbard U value.

`Integration`

- Type
Block

- Description
Options for the Voronoi numerical integration scheme. Deprecated. Use BeckeGrid instead.

`AccInt`

- Type
Float

- Default value
3.5

- Description
General parameter controlling the accuracy of the Voronoi integration grid. A value of 3 would be basic quality and a value of 7 would be good quality.

`IntegrationMethod`

- Type
Multiple Choice

- Default value
Becke

- Options
[Becke, Voronoi]

- Description
Choose the real-space numerical integration method. Note: the Voronoi integration scheme is deprecated.

`KGrpX`

- Type
Integer

- Default value
5

- GUI name
Number of K-points at once

- Description
Absolute upper bound on the number of k-points processed together. This only affects the computational performance.

`KSpace`

- Type
Block

- Description
Options for the k-space integration (i.e. the grid used to sample the Brillouin zone)

`Quality`

- Type
Multiple Choice

- Default value
Auto

- Options
[Auto, GammaOnly, Basic, Normal, Good, VeryGood, Excellent]

- GUI name
K-space

- Description
Select the quality of the K-space grid used to sample the Brillouin Zone. If ‘Auto’, the quality defined in the ‘NumericalQuality’ will be used. If ‘GammaOnly’, only one point (the gamma point) will be used. The actual number of K points generated depends on this option and on the size of the unit cell. The larger the real space cell, the fewer K points will be generated. The CPU-time and accuracy strongly depend on this option.

`Regular`

- Type
Block

- Description
Options for the regular k-space integration grid.

`NumberOfPoints`

- Type
Integer List

- Description
Use a regular grid with the specified number of k-points along each reciprocal lattice vector. For 1D periodic systems you should specify only one number, for 2D systems two numbers, and for 3D systems three numbers.

`Symmetric`

- Type
Block

- Description
Options for the symmetric k-space integration grid.

`KInteg`

- Type
Integer

- GUI name
Accuracy

- Description
Specify the accuracy for the Symmetric method. 1: absolutely minimal (only the G-point is used) 2: linear tetrahedron method, coarsest spacing 3: quadratic tetrahedron method, coarsest spacing 4,6,… (even): linear tetrahedron method 5,7…. (odd): quadratic method The tetrahedron method is usually by far inferior.

`Type`

- Type
Multiple Choice

- Default value
Regular

- Options
[Regular, Symmetric]

- GUI name
K-space grid type

- Description
The type of k-space integration grid used to sample the Brillouin zone (BZ) used. ‘Regular’: simple regular grid. ‘Symmetric’: symmetric grid for the irreducible wedge of the first BZ (useful when high-symmetry points in the BZ are needed to capture the correct physics of the system, graphene being a notable example).

`LDOS`

- Type
Block

- Description
Local Density-Of-States information. This can be used to generate STM images in the Tersoff-Hamann approximation (see https://doi.org/10.1103/PhysRevB.31.805)

`DeltaNeg`

- Type
Float

- Default value
0.0001

- Unit
Hartree

- Description
Lower bound energy (Shift-DeltaNeg)

`DeltaPos`

- Type
Float

- Default value
0.0001

- Unit
Hartree

- Description
Upper bound energy (Shift+DeltaPos)

`Shift`

- Type
Float

- Default value
0.0

- Unit
Hartree

- Description
The energy bias with respect to the Fermi level.

`MBPT`

- Type
Block

- Description
Technical aspects of the MP2 algorithm.

`Dependency`

- Type
Bool

- Default value
Yes

- Description
If true, to improve numerical stability, almost linearly-dependent combination of basis functions are removed from the Green’s function that are used in the MBPT equations. Disabling this key is strongly discouraged. Its value can however be changed. The key to adjust this value is RiHartreeFock%DependencyThreshold

`ExcludeCore`

- Type
Bool

- Description
If active, excludes core states from the calculation of the optimal imaginary time and frequency grids. The core states are still included in all parts of the calculations. In case a frozen care calculation is performed, this key is ignored. For MP2 and double hybrid calculation, it defaults to false. For RPA and GW calculations, it defaults to true.

`FitSetQuality`

- Type
Multiple Choice

- Default value
Auto

- Options
[Auto, VeryBasic, Basic, Normal, Good, VeryGood]

- Description
Specifies the fit set to be used in the MBPT calculation. ‘Normal’ quality is generally sufficient for basis sets up to and including TZ2P. For larger basis sets (or for benchmarking purposes) a ‘VeryGood’ fit set is recommended. Note that the FitSetQuality heavily influences the computational cost of the calculation. If not specified or ‘Auto’, the RIHartreeFock%FitSetQuality is used.

`Formalism`

- Type
Multiple Choice

- Default value
Auto

- Options
[Auto, RI, LT, All]

- Description
Specifies the formalism for the calculation of the MP2 correlation energy. ‘LT’ means Laplace Transformed MP2 (also referred to as AO-PARI-MP2), ‘RI’ means that a conventional RI-MP2 is carried out. If ‘Auto’, LT will be used in case of DOD double hybrids and SOS MP2, and RI will be used in all other cases. ‘All’ means that both RI and LT formalisms are used in the calculation. For a RPA or GW calculation, the formalism is always LT, irrespective of the formalism specified with this key.

`IntegrationQuality`

- Type
Multiple Choice

- Options
[VeryBasic, Basic, Normal, Good, VeryGood]

- Description
Specifies the integration quality to be used in the MBPT calculation. If not specified, the RIHartreeFock%IntegrationQuality is used.

`SigmaFunctionalParametrization`

- Type
Multiple Choice

- Default value
S1re

- Options
[W1, W2, S1, S2, S1re]

- Description
Only relevant if a sigma-functional calculation is performed. Possible choices for the parametrization of the sigma-functional. Not all options are supported for all functionals.

`ThresholdQuality`

- Type
Multiple Choice

- Options
[VeryBasic, Basic, Normal, Good, VeryGood, Excellent]

- Description
Controls the distances between atomic centers for which the product of two basis functions is not fitted any more. Especially for spatially extended, large systems, ‘VERYBASIC’ and ‘BASIC’ can lead to large computational savings, but the fit is also more approximate. If not specified, the RIHartreeFock%ThresholdQuality is used.

`UseScaledZORA`

- Type
Bool

- Default value
Yes

- Description
If true, use the scaled ZORA orbital energies instead of the ZORA orbital energies in the MBPT equations.

`frozencore`

- Type
Bool

- Default value
No

- Description
Freeze core states in correlation part of MBPT calculation

`nCore`

- Type
Integer

- Default value
0

- GUI name
Number of core levels

- Description
Number of core states which will be excluded from the correlated calculation. Will be ignored if frozencore is false. In case nothing is specified, the number of core levels will be determined automatically. Needs to be smaller than the number of occupied states.

`nFrequency`

- Type
Integer

- Default value
12

- GUI name
Number of frequency points

- Description
Number of imaginary frequency points. This key is only relevant for RPA and GW and will be ignored if used in an AO-PARI-MP2 calculation. 12 Points is the default for a RPA calculation. It is technically possible to use a different number of imaginary frequency points than for imaginary time. The maximum number of points which can be requested for imaginary frequency integration is 42. Important note: The computation time and memory requirements roughly scale linearly with the number of imaginary frequency points. However, memory can be an issue for RPA and GW when the number of imaginary frequency points is high. In case a job crashes, it is advised to increase the number of nodes since the necessary memory distributes over all nodes.

`nFrequencyG3W2`

- Type
Integer

- Default value
32

- GUI name
Number of frequency points for G3W2 integration

- Description
Number of imaginary frequency points for G3W2 integration

`nLambda`

- Type
Integer

- Default value
1

- GUI name
Number of lambda points

- Description
Size of coupling constant integration grid for SOSEX variants in RPA. Default is 4 points

`nTime`

- Type
Integer

- GUI name
Number of time points

- Description
Number of imaginary time points (only relevant in case the Laplace Transformed (LT) formalism is used). In the many-body-perturbation theory module in ADF, the polarizability (or Kohn-Sham density response function) is evaluated in imaginary time to exploit sparsity in the AO basis. For MP2, this is often referred to as a Laplace transform. For MP2, 9 points are the default. This is a safe choice, guaranteeing accuracies higher than 1 Kj/mol for most systems (For many simple organic systems, 6 points are sufficient for good accuracy). Only for systems with a very small HOMO-LUMO gap or low-lying core states (heavy elements starting from the 4th row of the periodic table) more points might be necessary. In principle, the same considerations apply for RPA and GW as well, however, the accuracy requirements are somewhat higher and 12 point are the default for RPA. In a GW calculation, the number of points is adjusted according to the numerical quality. Using less than 9 points is strongly discouraged except for the simplest molecules. In ADF2019, it can happen that the algorithm determining the imaginary time grid does not converge. In this case, the usual reason is that the number of points is too small and more points need to be specified. Starting from AMS2020, this does not happen any more. In case the imaginary time grid does not converge, the number of points is automatically adjusted until it does. The computation time of AO-PARI-MP2, RPA, and GW scales linearly with the number of imaginary time points.

`MolecularNMR`

- Type
Block

- Description
Options for the calculations of the NMR shielding tensor for molecules, excluding periodic systems. Implements the Schreckenbach method like ADF.

`Enabled`

- Type
Bool

- Default value
No

- Description
Compute NMR shielding.

`MultiSecantConfig`

- Type
Block

- Description
Parameters for the Multi-secant SCF convergence method.

`CMax`

- Type
Float

- Default value
20.0

- GUI name
Max coeff

- Description
Maximum coefficient allowed in expansion

`InitialSigmaN`

- Type
Float

- Default value
0.1

- GUI name
Initial

- Description
This is a lot like a mix factor: bigger means bolder

`MaxSigmaN`

- Type
Float

- Default value
0.3

- GUI name
Max

- Description
Upper bound for the SigmaN parameter

`MaxVectors`

- Type
Integer

- Default value
20

- GUI name
Number of cycles to use

- Description
Maximum number of previous cycles to be used

`MinSigmaN`

- Type
Float

- Default value
0.01

- GUI name
Min

- Description
Lower bound for the SigmaN parameter

`NEGF`

- Type
Block

- Description
Options for the NEGF (non-equilibrium green function) transport calculation.

`AlignChargeTol`

- Type
Float

- Default value
0.1

- Description
In an alignment run you want to get the number of electrons in the center right. This number specifies the criterion for that.

`AlignmentFile`

- Type
String

- Default value
- Description
Band result file (.rkf) corresponding to the alignment calculation.

`Alpha`

- Type
Float

- Default value
1e-05

- Description
A charge error needs to be translated in a potential shift. DeltaV = alpha * DeltaQ

`ApplyShift1`

- Type
Bool

- Default value
Yes

- Description
Apply the main shift, obtained from comparing matrix elements in the leads with those from the tight-binding run. Strongly recommended.

`ApplyShift2`

- Type
Bool

- Default value
Yes

- Description
Apply the smaller alignment shift. This requires an extra alignment run. Usually this shift is smaller.

`AutoContour`

- Type
Bool

- Default value
Yes

- Description
Use automatic contour integral.

`BiasPotential`

- Type
Float

- Default value
0.0

- Description
Apply a bias potential (atomic units). Can be negative. One has to specify the ramp potential with the FuzzyPotential key. This is mostly conveniently done with the GUI.

`BoundOccupationMethod`

- Type
Integer

- Default value
1

- Description
See text. Only relevant with NonEqDensityMethod equal 2 or 3.

`CDIIS`

- Type
Bool

- Default value
No

- Description
Make the normal DIIS procedure aware of the align charge error

`CheckOverlapTol`

- Type
Float

- Default value
0.01

- Description
BAND checks how well the TB overlap matrix S(R=0) represents the overlap matrix in the lead region. Elements corresponding to the outer layer are neglected, because when using a frozen core they have bigger errors.

`ContourQuality`

- Type
Multiple Choice

- Default value
good

- Options
[basic, normal, good, verygood]

- Description
The density matrix is calculated numerically via a contour integral. Changing the quality influences the number of points. This influences a lot the performance.

`DEContourInt`

- Type
Float

- Default value
-1.0

- Description
The energy interval for the contour grid. Defaults depends on the contour quality

`DERealAxisInt`

- Type
Float

- Default value
-1.0

- Description
The energy interval for the real axis grid. Defaults depends on the contour quality.

`DeltaPhi0`

- Type
Float

- Default value
0.0

- Description
Undocumented.

`DeltaPhi1`

- Type
Float

- Default value
0.0

- Description
Undocumented.

`DoAlignment`

- Type
Bool

- Default value
No

- Description
Set this to True if you want to do an align run. Between the leads there should be lead material. The GUI can be of help here.

`EMax`

- Type
Float

- Default value
5.0

- Unit
eV

- Description
The maximum energy for the transmission grid (with respect to the Fermi level of the lead)

`EMin`

- Type
Float

- Default value
-5.0

- Unit
eV

- Description
The minimum energy for the transmission grid (with respect to the Fermi level of the lead)

`Eta`

- Type
Float

- Default value
1e-05

- Description
Small value used for the contour integral: stay at least this much above the real axis. This value is also used for the evaluation of the Transmission and dos.

`IgnoreOuterLayer`

- Type
Bool

- Default value
Yes

- Description
Whether or not to ignore the outer layer.

`KT`

- Type
Float

- Default value
0.001

- Description
k-Boltzmann times temperature.

`LeadFile`

- Type
String

- Default value
- Description
File containing the tight binding representation of the lead.

`NE`

- Type
Integer

- Default value
100

- Description
The number of energies for the transmission energy grid.

`NonEqDensityMethod`

- Type
Integer

- Default value
1

- Description
See text.

`SGFFile`

- Type
String

- Default value
- Description
The result from the SGF program. Contains the Fermi energy of the lead.

`YContourInt`

- Type
Float

- Default value
0.3

- Description
The density is calculated via a contour integral. This value specifies how far above the real axis the (horizontal part of the) contour runs. The value is rounded in such a way that it goes exactly halfway between two Fermi poles. There is a trade off: making it bigger makes the integrand more smooth, but the number of enclosed poles increases. For low temperatures it makes sense to lower this value, and use a smaller deContourInt.

`YRealaxisInt`

- Type
Float

- Default value
1e-05

- Description
The non-Equilibrium density is calculated near the real axis.

`NeutralizingDensity`

- Type
Multiple Choice

- Default value
None

- Options
[None, rho(atoms), rho(valence/atoms), rho(neutralizing/atoms), rho(homogeneous)]

- Description
For charged systems an artificial compensating density can be used to make it neutral again. This fictitious density only affects the Coulomb potential. For charged periodic systems neutralization is required, as otherwise the Coulomb potential diverges.

`NeutralizingDensityDetails`

- Type
Block

- Description

`DiffuseFactor`

- Type
Float

- Default value
1.0

- Description
The bigger this number, the more diffuse (extended) the neutralizing density becomes. Works only for rho(neutralizing/atoms)

`HomogeneousDensity`

- Type
Block

- Description
xxx

`Origin`

- Type
Float List

- Default value
[0.0, 0.0, 0.0]

- Unit
Bohr

- Description

`Range`

- Type
Float

- Default value
10.0

- Unit
Bohr

- Description

`Width`

- Type
Float

- Default value
1.0

- Unit
Bohr

- Description

`NewResponse`

- Type
Block

- Description
The TD-CDFT calculation to obtain the dielectric function is computed when this block is present in the input. Several important settings can be defined here.

`ActiveESpace`

- Type
Float

- Default value
5.0

- Unit
eV

- GUI name
Active energy space

- Description
Modifies the energy threshold (DeltaE^{max}_{thresh} = omega_{high} + ActiveESpace) for which single orbital transitions (DeltaEpsilon_{ia} = Epsilon_{a}^{virtual} - Epsilon_{i}^{occupied}) are taken into account.

`ActiveXYZ`

- Type
String

- Default value
t

- Description
Expects a string consisting of three letters of either ‘T’ (for true) or ‘F’ (for false) where the first is for the X-, the second for the Y- and the third for the Z-component of the response properties. If true, then the response properties for this component will be evaluated.

`DensityCutOff`

- Type
Float

- Default value
0.001

- GUI name
Volume cutoff

- Description
For 1D and 2D systems the unit cell volume is undefined. Here, the volume is calculated as the volume bordered by the isosurface for the value DensityCutoff of the total density.

`EShift`

- Type
Float

- Default value
0.0

- Unit
eV

- GUI name
Shift

- Description
Energy shift of the virtual crystal orbitals.

`FreqHigh`

- Type
Float

- Default value
3.0

- Unit
eV

- Description
Upper limit of the frequency range for which response properties are calculated (omega_{high}).

`FreqLow`

- Type
Float

- Default value
1.0

- Unit
eV

- Description
Lower limit of the frequency range for which response properties are calculated. (omega_{low})

`NFreq`

- Type
Integer

- Default value
5

- Description
Number of frequencies for which a linear response TD-CDFT calculation is performed.

`NewResponseKSpace`

- Type
Block

- Description
Modify the details for the integration weights evaluation in reciprocal space for each single-particle transition. Only influencing the NewResponse code.

`Eta`

- Type
Float

- Default value
1e-05

- Description
Defines the small, finite imaginary number i*eta which is necessary in the context of integration weights for single-particle transitions in reciprocal space.

`SubSimp`

- Type
Integer

- Default value
3

- Description
determines into how many sub-integrals each integration around a k point is split. This is only true for so-called quadratic integration grids. The larger the number the better the convergence behavior for the sampling in reciprocal space. Note: the computing time for the weights is linear for 1D, quadratic for 2D and cubic for 3D!

`NewResponseSCF`

- Type
Block

- Description
Details for the linear-response self-consistent optimization cycle. Only influencing the NewResponse code.

`Bootstrap`

- Type
Integer

- Default value
0

- Description
defines if the Berger2015 kernel (Bootstrap 1) is used or not (Bootstrap 0). If you chose the Berger2015 kernel, you have to set NewResponseSCF%XC to ‘0’. Since it shall be used in combination with the bare Coulomb response only. Note: The evaluation of response properties using the Berger2015 is recommend for 3D systems only!

`COApproach`

- Type
Bool

- Default value
Yes

- Description
The program automatically decides to calculate the integrals and induced densities via the Bloch expanded atomic orbitals (AO approach) or via the cyrstal orbitals (CO approach). The option COApproach overrules this decision.

`COApproachBoost`

- Type
Bool

- Default value
No

- GUI name
CO Approach Boost

- Description
Keeps the grid data of the Crystal Orbitals in memory. Requires significantly more memory for a speedup of the calculation. One might have to use multiple computing nodes to not run into memory problems.

`Criterion`

- Type
Float

- Default value
0.001

- Description
For the SCF convergence the RMS of the induced density change is tested. If this value is below the Criterion the SCF is finished. Furthermore, one can find the calculated electric susceptibility for each SCF step in the output and can therefore decide if the default value is too loose or too strict.

`DIIS`

- Type
Block

- Description
Parameters influencing the DIIS self-consistency method

`Enabled`

- Type
Bool

- Default value
Yes

- Description
If not enabled simple mixing without DIIS acceleration will be used.

`MaxSamples`

- Type
Integer

- Default value
10

- Description
Specifies the maximum number of samples considered during the direct inversion of iteration of subspace (DIIS) extrapolation of the atomic charges during the SCC iterations. A smaller number of samples potentially leads to a more aggressive convergence acceleration, while a larger number often guarantees a more stable iteration. Due to often occurring linear dependencies within the set of sample vectors, the maximum number of samples is reached only in very rare cases.

`MaximumCoefficient`

- Type
Float

- Default value
10.0

- Description
When the diis expansion coefficients exceed this threshold, the solution is rejected. The vector space is too crowded. The oldest vector is discarded, and the expansion is re-evaluated.

`MinSamples`

- Type
Integer

- Default value
-1

- Description
When bigger than one, this affects the shrinking of the DIIS space on linear dependence. It will not reduce to a smaller space than MinSamples unless there is extreme dependency.

`MixingFactor`

- Type
Float

- Default value
0.2

- Description
The parameter used to mix the DIIS linear combination of previously sampled atomic charge vectors with an analogous linear combination of charge vectors resulting from population analysis combination. It can assume real values between 0 and 1.

`LowFreqAlgo`

- Type
Bool

- Default value
Yes

- GUI name
Low Frequency Algorithm

- Description
Numerically more stable results for frequencies lower than 1.0 eV. Note: for a graphene monolayer the conical intersection results in a very small band gap (zero band gap semi-conductor). This leads ta a failing low frequency algorithm. One can then chose to use the algorithm as originally proposed by Kootstra by setting the input value to *false*. But, this can result in unreliable results for frequencies lower than 1.0 eV!

`NCycle`

- Type
Integer

- Default value
20

- GUI name
Cycles

- Description
Number of SCF cycles for each frequency to be evaluated.

`XC`

- Type
Integer

- Default value
1

- Description
Influences if the bare induced Coulomb response (XC 0) is used for the effective, induced potential or the induced potential derived from the ALDA kernel as well (XC 1).

`NMR`

- Type
Block

- Description
Options for the calculations of the NMR shielding tensor.

`Correction_r`

- Type
Bool

- Default value
Yes

- Description
Undocumented.

`Enabled`

- Type
Bool

- Default value
No

- Description
Compute NMR shielding.

`MS0`

- Type
Float

- Default value
0.01

- Description
Undocumented.

`NMRAtom`

- Type
Integer

- Default value
0

- Description
The index of the atom atom (in input order) for which NMR should be computed.

`Numeric`

- Type
Bool

- Default value
No

- Description
Undocumented.

`Original`

- Type
Bool

- Default value
No

- Description
Undocumented.

`Print_jp`

- Type
Bool

- Description
Print paramagnetic current.

`SuperCell`

- Type
Bool

- Default value
Yes

- Description
This is the switch between the two methods, either the super cell (true), or the single-dipole method (false)

`Test`

- Type
Bool

- Description
Key for printing all intrinsic tensors.

`Test_E`

- Type
Bool

- Description
Test of energy levels.

`Test_S`

- Type
Bool

- Description
Test of overlap matrix.

`UseSharedMemory`

- Type
Bool

- Default value
Yes

- Description
Whether or not to use shared memory in the NMR calculation.

`NOCVdRhoPlot`

- Type
Non-standard block

- Description
Goes together with the Restart%NOCVdRhoPlot and Grid keys. See example.

`NOCVOrbitalPlot`

- Type
Non-standard block

- Description
Goes together with the Restart%NOCVOrbitalPlot and Grid keys. See example.

`NuclearModel`

- Type
Multiple Choice

- Default value
PointCharge

- Options
[PointCharge, Gaussian, Uniform]

- Description
Specify what model to use for the nucleus. For the Gaussian model the nuclear radius is calculated according to the work of Visscher and Dyall (L. Visscher, and K.G. Dyall, Dirac-Fock atomic electronic structure calculations using different nuclear charge distributions, Atomic Data and Nuclear Data Tables 67, 207 (1997))

`NUElstat`

- Type
Integer

- Default value
50

- Description
Number of outward (parabolic) integration points (for elliptical integration of the electrostatic interaction)

`NumericalQuality`

- Type
Multiple Choice

- Default value
Normal

- Options
[Basic, Normal, Good, VeryGood, Excellent]

- Description
Set the quality of several important technical aspects of a BAND calculation (with the notable exception of the basis set). It sets the quality of: BeckeGrid (numerical integration), ZlmFit (density fitting), KSpace (reciprocal space integration), and SoftConfinement (basis set confinement). Note: the quality defined in the block of a specific technical aspects supersedes the value defined in NumericalQuality (e.g. if I specify ‘NumericalQuality Basic’ and ‘BeckeGrid%Quality Good’, the quality of the BeckeGrid will be ‘Good’)

`NVElstat`

- Type
Integer

- Default value
80

- Description
Number of angular (elliptic) integration points (for elliptical integration of the electrostatic interaction)

`Occupations`

- Type
Non-standard block

- Description
Allows one to input specific occupations numbers. Applies only for calculations that use only one k-point (i.e. pseudo-molecule calculations). See example.

`OldResponse`

- Type
Block

- Description
Options for the old TD-CDFT implementation.

`Berger2015`

- Type
Bool

- Default value
No

- Description
Use the parameter-free polarization functional by A. Berger (Phys. Rev. Lett. 115, 137402). This is possible for 3D insulators and metals. Note: The evaluation of response properties using the Berger2015 is recommend for 3D systems only!

`CNT`

- Type
Bool

- Description
Use the CNT parametrization for the longitudinal and transverse kernels of the XC kernel of the homogeneous electron gas. Use this in conjunction with the NewVK option.

`CNVI`

- Type
Float

- Default value
0.001

- Description
The first convergence criterion for the change in the fit coefficients for the fit functions, when fitting the density.

`CNVJ`

- Type
Float

- Default value
0.001

- Description
the second convergence criterion for the change in the fit coefficients for the fit functions, when fitting the density.

`Ebndtl`

- Type
Float

- Default value
0.001

- Unit
Hartree

- Description
the energy band tolerance, for determination which routines to use for calculating the numerical integration weights, when the energy band posses no or to less dispersion.

`Enabled`

- Type
Bool

- Default value
No

- Description
If true, the response function will be calculated using the old TD-CDFT implementation

`Endfr`

- Type
Float

- Default value
3.0

- Unit
eV

- Description
The upper bound frequency of the frequency range over which the dielectric function is calculated

`Isz`

- Type
Integer

- Default value
0

- Description
Integer indicating whether or not scalar zeroth order relativistic effects are included in the TDCDFT calculation. 0 = relativistic effects are not included, 1 = relativistic effects are included. The current implementation does NOT work with the option XC%SpinOrbitMagnetization equal NonCollinear

`Iyxc`

- Type
Integer

- Default value
0

- Description
integer for printing yxc-tensor (see http://aip.scitation.org/doi/10.1063/1.1385370). 0 = not printed, 1 = printed.

`NewVK`

- Type
Bool

- Description
Use the slightly modified version of the VK kernel (see https://aip.scitation.org/doi/10.1063/1.1385370). When using this option one uses effectively the static option, even for metals, so one should check carefully the convergence with the KSPACE parameter.

`Nfreq`

- Type
Integer

- Default value
5

- Description
the number of frequencies for which a linear response TD-CDFT calculation is performed.

`QV`

- Type
Bool

- Description
Use the QV parametrization for the longitudinal and transverse kernels of the XC kernel of the homogeneous electron gas. Use this in conjunction with the NewVK option. (see reference).

`Shift`

- Type
Float

- Default value
0.0

- Unit
eV

- Description
energy shift for the virtual crystal orbitals.

`Static`

- Type
Bool

- Description
An alternative method that allows an analytic evaluation of the static response (normally the static response is approximated by a finite small frequency value). This option should only be used for non-relativistic calculations on insulators, and it has no effect on metals. Note: experience shows that KSPACE convergence can be slower.

`Strtfr`

- Type
Float

- Default value
1.0

- Unit
eV

- Description
is the lower bound frequency of the frequency range over which the dielectric function is calculated.

`OrbitalPlot`

- Type
Non-standard block

- Description
Goes together with the Restart%OrbitalPlot and Grid keys. See Example.

`Output`

- Type
Block

- Description
Control the output.

`Print`

- Type
Block

- Recurring
True

- Description

`Level`

- Type
Multiple Choice

- Options
[None, Error, Warning, Minimal, Normal, Detail, TooMuchDetail]

- Description

`Section`

- Type
Multiple Choice

- Options
[Prepare, SCF, Properties]

- Description

`OverlapPopulations`

- Type
Non-standard block

- Description
Overlap population weighted DOS (OPWDOS), also known as the crystal orbital overlap population (COOP).

`PEDA`

- Type
Bool

- Default value
No

- Description
If present in combination with the fragment block, the decomposition of the interaction energy between fragments is invoked.

`PEDANOCV`

- Type
Block

- Description
Options for the decomposition of the orbital relaxation (pEDA).

`EigvalThresh`

- Type
Float

- Default value
0.001

- GUI name
Use NOCVs with ev larger than

- Description
The threshold controls that for all NOCV deformation densities with NOCV eigenvalues larger than EigvalThresh the energy contribution will be calculated and the respective pEDA-NOCV results will be printed in the output

`Enabled`

- Type
Bool

- Default value
No

- GUI name
Perform PEDA-NOCV analysis

- Description
If true in combination with the fragment blocks and the pEDA key, the decomposition of the orbital relaxation term is performed.

`PeriodicSolvation`

- Type
Block

- Description
Additional options for simulations of periodic structures with solvation.

`NStar`

- Type
Integer

- Default value
4

- Description
This option, expecting an integer number (>2), handles the accuracy for the construction of the COMSO surface. The larger the given number the more accurate the construction.

`RemovePointsWithNegativeZ`

- Type
Bool

- Default value
No

- GUI name
Only above slab

- Description
Whether the COSMO surface is constructed on both sides of a surface. If one is only interested in the solvation effect on the upper side of a surface (in the Z direction), then this option should be set to ‘True’

`SymmetrizeSurfacePoints`

- Type
Bool

- Default value
Yes

- Description
Whether or not the COSMO point should be symmetrized

`PopThreshold`

- Type
Float

- Default value
0.01

- Description
Threshold for printing Mulliken population terms. Works with ‘Print orbpop’

`PotentialNoise`

- Type
Float

- Default value
0.0001

- Description
The initial potential for the SCF procedure is constructed from a sum-of-atoms density. Added to this is some small noise in the numerical values of the potential in the points of the integration grid. The purpose of the noise is to help the program break the initial symmetry, if that would lower the energy, by effectively inducing small differences between (initially) degenerate orbitals.

`Print`

- Type
String

- Recurring
True

- Description
One or more strings (separated by blanks) from a pre-defined set may be typed after the key. This induces printing of various kinds of information, usually only used for debugging and checking. The set of recognized strings frequently changes (mainly expands) in the course of software-developments. Useful arguments may be symmetry, and fit.

`Programmer`

- Type
Block

- Description
Miscellaneous technical options.

`SharedMemorySandwichingThreshold`

- Type
Integer

- Default value
5000

- Description
When the nr. of basis functions exceeds this threshold shared memory will be used to calculate matrix elements. Unless UseSharedMemoryForSandwiching is explicitly set in the input.

`StoreDOSPerBas`

- Type
Bool

- Default value
Yes

- Description
Whether or not to store the parial DOS per basis function. This allows you to view any partial DOS with amsspectra and amsbands. Requires the CalcPDOS option to be on.

`StoreOrbitals`

- Type
Bool

- Default value
Yes

- Description
Copy information on band.rkf needed for orbital plotting and restarts. This can be a lot of information. DOS and BandStructure require StoreOrbitals=true.

`UpdateSTDVec`

- Type
Bool

- Default value
Yes

- Description
Shift atoms so that center of mass is at zero. As a results the detected symmetry may be higher.

`UseSharedMemoryForSandwiching`

- Type
Bool

- Default value
Yes

- GUI name
Use shared memory

- Description
When calculating matrix elements the array will be shared. This saves memory at the cost of locking overhead. If not specified this will depend on the threshold SharedMemorySandwichingThreshold

`UseTurnoverRuleForXcMatrix`

- Type
Bool

- Default value
No

- Description
Undocumented.

`Usesharedmemory`

- Type
Bool

- Default value
Yes

- GUI name
Use shared memory

- Description
When running more then one task, share memory between those tasks. This saves a lot of memory. Only disable it in case of problems.

`PropertiesAtNuclei`

- Type
Non-standard block

- Description
A number of properties can be obtained near the nucleus. An average is taken over a tiny sphere around the nucleus. The following properties are available: vxc[rho(fit)], rho(fit), rho(scf), v(coulomb/scf), rho(deformation/fit), rho(deformation/scf).

`RadialDefaults`

- Type
Block

- Description
Options for the logarithmic radial grid of the basis functions used in the subprogram Dirac

`NR`

- Type
Integer

- Default value
3000

- Description
Number of radial points. With very high values (like 30000) the Dirac subprogram may not converge.

`NRPerType`

- Type
Integer List

- Description
If present overrides NR. The list needs to be as long as there are atom types

`RMax`

- Type
Float

- Default value
100.0

- Unit
Bohr

- Description
Upper bound of the logarithmic radial grid

`RMin`

- Type
Float

- Default value
1e-06

- Unit
Bohr

- Description
Lower bound of the logarithmic radial grid

`RMinPerType`

- Type
Float List

- Unit
Bohr

- Description
If specified overrides RMin. The list needs to be as long as there are atom types (different elements)

`Relativity`

- Type
Block

- Description
Options for relativistic effects.

`Level`

- Type
Multiple Choice

- Default value
Scalar

- Options
[None, Scalar, Spin-Orbit]

- GUI name
Relativity (ZORA)

- Description
None: No relativistic effects. Scalar: Scalar relativistic ZORA. This option comes at very little cost. SpinOrbit: Spin-orbit coupled ZORA. This is the best level of theory, but it is (4-8 times) more expensive than a normal calculation. Spin-orbit effects are generally quite small, unless there are very heavy atoms in your system, especially with p valence electrons (like Pb). See also the SpinOrbitMagnetization key.

`ResponseInducedDensityPlot`

- Type
Non-standard block

- Description
Goes together with Restart%ResponseInducedDensityPlot and Grid.

`Restart`

- Type
Block

- Description
Tells the program that it should restart with the restart file, and what to restart.

`BandStructure`

- Type
Bool

- Default value
No

- Description
Calculate the band structure from a previous calculation. Does not work with model potentials and Hubbard.

`CheckAtomicPositions`

- Type
Bool

- Default value
Yes

- Description
If set to True: For restarting the SCF the atomic positions will be checked, and may not deviate too much.

`DOS`

- Type
Bool

- Default value
No

- Description
Calculate the DOS from a previous calculation. Does not work with model potentials and Hubbard.

`DensityPlot`

- Type
Bool

- Default value
No

- Description
Goes together with the DensityPlot block and Grid blocks

`File`

- Type
String

- Default value
- Description
Name of the restart file.

`LoadEigenSystem`

- Type
Bool

- Default value
No

- GUI name
Load: eigen system

- Description
At each step of the SCF load the section eigensystem from the restart file, forcing constant eigenvalues and vectors.

`NOCVOrbitalPlot`

- Type
Bool

- Default value
No

- Description
Goes together with the NOCVOrbitalPlot and Grid blocks.

`NOCVdRhoPlot`

- Type
Bool

- Default value
No

- Description
Goes together with the NOCVdRhoPlot and Grid blocks.

`OrbitalPlot`

- Type
Bool

- Default value
No

- Description
Goes together with the OrbitalPlot and Grid

`ResponseInducedDensityPlot`

- Type
Bool

- Default value
No

- Description
Goes together with the ResponseInducedDensityPlot and Grid blocks.

`SCF`

- Type
Bool

- Default value
No

- GUI name
Restart: SCF

- Description
Continue the SCF procedure using the orbital coefficients and occupations from the restart file.

`UseDensityMatrix`

- Type
Bool

- Default value
No

- Description
If set to True: For restarting the SCF the density matrix will be used. Requires you to set ‘Save DensityMatrix’ in the previous run.

`VTKFile`

- Type
String

- Default value
- Description
If specified a vtk file with be created with this name. If the extension is ‘.txt’, a text file is created. Setting it to ‘CUBE’ one or more (one for each component) files in the cube format are generated with an automatic naming scheme.

`VoronoiGrid`

- Type
Bool

- Default value
No

- Description
Copy the section Num In Params to the current file.

`RIHartreeFock`

- Type
Block

- Description

`DependencyCoreRange`

- Type
Float

- Description
Basis functions may be given a core character based on the range. For now only active in Band and only if present in the input

`DependencyThreshold`

- Type
Float

- Default value
0.001

- Description
To improve numerical stability, almost linearly-dependent combination of basis functions are removed from the Hartree-Fock exchange matrix. If you obtain unphysically large bond energy in an Hybrid calculation, or an unphysically low correlation energy in an RPA, MP2, or double hybrid calculation, you might try setting the DependencyThreshold to a larger value (e.g. 3.0E-3) Note, that in GW calculations and GW-BSE calculations the default for this key is 5.0e-3.

`FitGenerationDetails`

- Type
Block

- Description
Technical details about how the RI Hartree-Fock fit functions are generated.

`BoostL`

- Type
Bool

- Default value
No

- Description
Add extra max(l)+1 diffuse function When l denotes the highest angular momentum present in the primary basis, FromBasisProducts will generate auxiliary fit functions with up to 2l angular momentum. When this key is set to true, the maximum angular momentum in the auxiliary fit set becomes 2l+2. Typically, this option is not needed and when precision issues arise, it is rather advised to adjust the OneCenterDependencyThreshold key to a smaller value.

`LapackWorkAround`

- Type
Bool

- Default value
No

- Description
GetFitFunctionsForAtomType diagonalization done with Lapack instead of Scalapack

`Method`

- Type
Multiple Choice

- Default value
Auto

- Options
[Auto, FromBasisProducts]

- Description
The way in which fit functions are generated. The main distinction is whether it depends on the basis functions used. When FromBasisProducts is used, the auxiliary basis is generated directly from the products of primary basis functions. This has the advantage that the auxiliary fit adapts automatically to the basis set size. Especially for basis sets of QZ quality or larger, this is often necessary to obtain highly precise correlation energies using RPA or double hybrids FromBasisProducts option is also useful for GW or BSE calculations with basis sets of QZ quality or larger.

`OneCenterDependencyThreshold`

- Type
Float

- Default value
1e-08

- Description
This key is only active when FromBasisProducts is chosen as method to generate the auxiliary basis. This threshold controls the size, and at the samw time, the precision of the auxiliary basis set. A smaller number leads to a larger auxiliary fit set. The default value of 1e-8 is typically sufficient to converge correlation energies and QP energies to a very high precision. It corresponds to an auxiliary basis which is typically 8-9 times larger than the primary basis.

`UseBandRadialGrid`

- Type
Bool

- Default value
Yes

- Description
Only applies to band. The band logarithmic grid ranges (by default) from 1e-6 to 100 with 3000 points. Otherwise 300 points will be used. For 0-periodicity (molecules) it is advisable to set this key to false since lots of memory is needed to evaluate all necessary integrals.

`FitSetQuality`

- Type
Multiple Choice

- Default value
Auto

- Options
[Auto, VeryBasic, Basic, Normal, Good, VeryGood, Excellent, FromBasisProducts]

- Description
The quality of auxiliary fit set employed in the RI scheme. If ‘Auto’, the value of the RIHartreeFock Quality option will be used. Normal quality is generally sufficient for basis sets up to and including TZ2P. For larger basis sets (or for benchmarking purposes) a VeryGood fit set is recommended. Note that the FitSetQuality heavily influences the computational cost of the calculation.

`IntegrationQuality`

- Type
Multiple Choice

- Options
[VeryBasic, Basic, Normal, Good, VeryGood, Excellent]

- Description
Quality of the numerical integration for evaluating the integrals between basis functions and fit functions. If IntegrationQuality is not defined in input, the value defined in RIHartreeFock%Quality will be used.

`Quality`

- Type
Multiple Choice

- Default value
Auto

- Options
[Auto, VeryBasic, Basic, Normal, Good, VeryGood, Excellent]

- Description
Numerical accuracy of the RI procedure. If ‘Auto’, the quality specified in the ‘NumericalQuality’ will be used.

`QualityPerRegion`

- Type
Block

- Recurring
True

- Description
Sets the fit-set quality for all atoms in a region. If specified, this overwrites the globally set quality.

`Quality`

- Type
Multiple Choice

- Options
[VeryBasic, Basic, Normal, Good, VeryGood, Excellent]

- Description
This region’s quality of the auxiliary fit set employed in the RI scheme.

`Region`

- Type
String

- Description
The identifier of the region for which to set the quality.

`ResponseQuality`

- Type
Multiple Choice

- Options
[VeryBasic, Basic, Normal, Good, VeryGood, Excellent]

- Description
Numerical accuracy of the RI procedure for the Response module.

`ThresholdQuality`

- Type
Multiple Choice

- Options
[VeryBasic, Basic, Normal, Good, VeryGood, Excellent]

- Description
Linear scaling thresholds (also used for determining at what range the multiple approximation is used). To disable all linear scaling thresholds set this to Excellent.

`UseMe`

- Type
Bool

- Default value
Yes

- Description
Set to False if you want to use the old RI scheme (ADF only)

`Save`

- Type
String

- Recurring
True

- Description
Save scratch files or extra data that would be otherwise deleted at the end of the calculation. e.g. ‘TAPE10’ (containing the integration grid) or ‘DensityMatrix’

`SCF`

- Type
Block

- Description
Controls technical SCF parameters.

`Eigenstates`

- Type
Bool

- Description
The program knows two alternative ways to evaluate the charge density iteratively in the SCF procedure: from the P-matrix, and directly from the squared occupied eigenstates. By default the program actually uses both at least one time and tries to take the most efficient. If present, Eigenstates turns off this comparison and lets the program stick to one method (from the eigenstates).

`Iterations`

- Type
Integer

- Default value
300

- GUI name
Maximum number of cycles

- Description
The maximum number of SCF iterations to be performed.

`Method`

- Type
Multiple Choice

- Default value
MultiStepper

- Options
[DIIS, MultiSecant, MultiStepper]

- Description
Choose the general scheme used to converge the density in the SCF. In case of scf problems one can try the MultiSecant alternative at no extra cost per SCF cycle. For more details see the DIIS and MultiSecantConfig block.

`Mixing`

- Type
Float

- Default value
0.075

- Description
Initial ‘damping’ parameter in the SCF procedure, for the iterative update of the potential: new potential = old potential + mix (computed potential-old potential). Note: the program automatically adapts Mixing during the SCF iterations, in an attempt to find the optimal mixing value.

`MultiStepperPresetPath`

- Type
String

- Default value
DFTB/default2023.inc

- Description
Name of file containing a SCFMultiStepper key block. This will be used if no Explicit SCFMultiStepper block is in the input, and Method=MultiStepper. If the path is not absolute, it is relative to $AMSHOME/data/presets/multi_stepper’

`PMatrix`

- Type
Bool

- Description
If present, evaluate the charge density from the P-matrix. See also the key Eigenstates.

`PrintAllOccupiedBands`

- Type
Bool

- Default value
Yes

- Description
When printing the ranges of the bands, include all occupied ones.

`PrintAllVirtualBands`

- Type
Bool

- Default value
No

- Description
When printing the ranges of the bands, include all virtual ones.

`PrintAlwaysBandRanges`

- Type
Bool

- Default value
No

- Description
Normally the ranges of the bands are only printed at the last SCF cycle

`Rate`

- Type
Float

- Default value
0.99

- Description
Minimum rate of convergence for the SCF procedure. If progress is too slow the program will take measures (such as smearing out occupations around the Fermi level, see key Degenerate of block Convergence) or, if everything seems to fail, it will stop

`SCFMultiStepper`

- Type
Block

- Description
To solve the self-consistent problem multiple steppers can be tried during stints using the ones that give the best progress.

`AlwaysChangeStepper`

- Type
Bool

- Default value
No

- Description
When the progress is fine there is no reason to change the stepper. In practice this is always set to true, because also the Stepper%ExpectedSlope can be used to achieve similar behavior.

`ErrorGrowthAbortFactor`

- Type
Float

- Default value
1000.0

- Description
Abort stint when the error grows too much, compared to the error at the start of the stint.

`FractionalStepFactor`

- Type
Float

- Default value
-1.0

- Description
Multiply the step by this factor. If smaller than zero this is not used.

`MinStintCyclesForAbort`

- Type
Integer

- Default value
0

- Description
Look at ErrorGrowthAbortFactor only when a number of steps has been completed since the start of the stint. A value of 0 means always.

`Stepper`

- Type
Block

- Recurring
True

- Description
??

`AbortSlope`

- Type
Float

- Default value
100.0

- Description
If the slope (at the end of a stint) is larger than this: abort the stepper

`DIISStepper`

- Type
Block

- Description
DIIS stepper

`EDIISAlpha`

- Type
Float

- Default value
0.01

- Description
The extra energy vector is weighed by this factor. .

`MaxCoefficient`

- Type
Float

- Default value
20.0

- Description
The largest allowed value of the expansion coefficients. If exceed the number of vectors is reduces until the criterion is met.

`MaxVectors`

- Type
Integer

- Default value
10

- Description
Maximum number of previous densities to be used (size of the history).

`MinVectors`

- Type
Integer

- Default value
-1

- Description
Try to prevent to make nVectors shrink below this value, by allowing for significantly larger coefficients.

`Mix`

- Type
Float

- Default value
0.2

- Description
Also known as greed. It determines the amount of output density to be used. May be changed by the MixAdapter.

`ErrorGrowthAbortFactor`

- Type
Float

- Default value
-1.0

- Description
Abort stint when the error grows too much, compared to the error at the start of the stint. Overrides global ErrorGrowthAbortFactor when set to a value > 0

`ExpectedSlope`

- Type
Float

- Default value
-100.0

- Description
If the slope of the total SCF is better than this keep on going.

`FractionalStepFactor`

- Type
Float

- Default value
-1.0

- Description
Multiply the step by this factor. If smaller than zero this is not used.

`MaxInitialError`

- Type
Float

- Description
Only use the stepper when error is smaller than this.

`MaxIterationNumber`

- Type
Integer

- Default value
-1

- Description
Stepper will only be active for iterations smaller than this number. (Negative value means: Ignore this option)

`MaxStintNumber`

- Type
Integer

- Default value
-1

- Description
Stepper will only be active for stints smaller than this number. (Negative value means: Ignore this option)

`MinInitialError`

- Type
Float

- Description
Only use the stepper when error is larger than this.

`MinIterationNumber`

- Type
Integer

- Default value
-1

- Description
Stepper will only be active for iterations larger than this number.

`MinStintCyclesForAbort`

- Type
Integer

- Default value
0

- Description
Look at ErrorGrowthAbortFactor only when a number of steps has been completed since the start of the stint. A value of 0 means always. Overrides global value.

`MinStintNumber`

- Type
Integer

- Default value
-1

- Description
Stepper will only be active for stints larger than this number.

`MixAdapter`

- Type
Block

- Description
Generic mix adapter

`ErrorGrowthPanicFactor`

- Type
Float

- Default value
10.0

- Description
When the error increases more than this factor, this mix is reduced a lot.

`GrowthFactor`

- Type
Float

- Default value
1.1

- Description
When the mix is considered too low it is multiplied by this factor. Otherwise it is divided by it.

`MaxMix`

- Type
Float

- Default value
0.3

- Description
Do not grow the mix above this value.

`MinMix`

- Type
Float

- Default value
0.1

- Description
Do not shrink the mix below this value.

`NTrialMixFactors`

- Type
Integer

- Default value
3

- Description
Only used with Type=Trial. Must be an odd number.

`TrialMode`

- Type
Multiple Choice

- Default value
CurrentMixCentered

- Options
[CurrentMixCentered, FullRange]

- Description
How are the NTrialMixFactors chosen?

`Type`

- Type
Multiple Choice

- Default value
Error

- Options
[Error, Energy, UnpredictedStep, Trial]

- Description
Adapt the mix factor based on the observed progress (slope).

`MixStepper`

- Type
Block

- Description
Simple mixing stepper, only using the previous (in/out) density.

`Mix`

- Type
Float

- Default value
0.1

- Description
???.

`MultiSecantStepper`

- Type
Block

- Description
Multi secant stepper.

`MaxCoefficient`

- Type
Float

- Default value
20.0

- Description
???.

`MaxVectors`

- Type
Integer

- Default value
10

- Description
???.

`Mix`

- Type
Float

- Default value
0.2

- Description
???.

`Variant`

- Type
Multiple Choice

- Default value
MSB2

- Options
[MSB1, MSB2, MSR1, MSR1s]

- Description
There are several version of the Multi secant method.

`StintLength`

- Type
Integer

- Description
Override global StintLength.

`StintLength`

- Type
Integer

- Default value
10

- Description
A stepper is active during a number of SCF cycles, called a stint.

`UsePreviousStintForErrorGrowthAbort`

- Type
Bool

- Default value
No

- Description
The error is normally checked against the first error of the stint. With this option that will be the one from the previous stint, if performed with the same stepper.

`VSplit`

- Type
Float

- Default value
0.05

- Description
To disturb degeneracy of alpha and beta spin MOs the value of this key is added to the beta spin potential at the startup.

`Screening`

- Type
Block

- Description
For the periodic solvation potential and for the old (not default anymore) fitting method, BAND performs lattice summations which are in practice truncated. The precision of the lattice summations is controlled by the options in this block.

`CutOff`

- Type
Float

- Description
Criterion for negligibility of tails in the construction of Bloch sums. Default depends on Accuracy.

`DMadel`

- Type
Float

- Description
One of the parameters that define the screening of Coulomb-potentials in lattice sums. Depends by default on Accuracy, rmadel, and rcelx. One should consult the literature for more information

`NoDirectionalScreening`

- Type
Bool

- Description
Real space lattice sums of slowly (or non-) convergent terms, such as the Coulomb potential, are computed by a screening technique. In previous releases, the screening was applied to all (long-range) Coulomb expressions. Screening is only applied in the periodicity directions. This key restores the original situation: screening in all directions

`RCelx`

- Type
Float

- Description
Max. distance of lattice site from which tails of atomic functions will be taken into account for the Bloch sums. Default depends on Accuracy.

`RMadel`

- Type
Float

- Description
One of the parameters that define screening of the Coulomb potentials in lattice summations. Depends by default on Accuracy, dmadel, rcelx. One should consult the literature for more information.

`SelectedAtoms`

- Type
Integer List

- Description
With this key you can select atoms. This has an effect on a few of options, like NMR and EFG.

`Skip`

- Type
String

- Recurring
True

- Description
Skip the specified part of the Band calculation (expert/debug option).

`SoftConfinement`

- Type
Block

- Description
In order to make the basis functions more compact, the radial part of the basis functions is multiplied by a Fermi-Dirac (FD) function (this ‘confinement’ is done for efficiency and numerical stability reasons). A FD function goes from one to zero, controlled by two parameters. It has a value 0.5 at Radius, and the decay width is Delta.

`Delta`

- Type
Float

- Unit
Bohr

- Description
Explicitly specify the delta parameter of the Fermi-Dirac function (if not specified, it will be 0.1*Radius).

`Quality`

- Type
Multiple Choice

- Default value
Auto

- Options
[Auto, Basic, Normal, Good, VeryGood, Excellent]

- GUI name
Confinement

- Description
In order to make the basis functions more compact, the radial part of the basis functions is multiplied by a Fermi-Dirac (FD) function (this ‘confinement’ is done for efficiency and numerical stability reasons). A FD function goes from one to zero, controlled by two parameters. It has a value 0.5 at Radius, and the decay width is Delta. This key sets the two parameters ‘Radius’ and ‘Delta’. Basic: Radius=7.0, Delta=0.7; Normal: Radius=10.0, Delta=1.0; Good: Radius=20.0, Delta=2.0; VeryGood and Excellent: no confinement at all. If ‘Auto’, the quality defined in the ‘NumericalQuality’ will be used.

`Radius`

- Type
Float

- Unit
Bohr

- Description
Explicitly specify the radius parameter of the Fermi-Dirac function.

`Solvation`

- Type
Block

- Description
Options for the COSMO (Conductor like Screening Model) solvation model.

`CVec`

- Type
Multiple Choice

- Default value
EXACT

- Options
[EXACT, FITPOT]

- GUI name
Calculate Coulomb interaction

- Description
Choose how to calculate the Coulomb interaction matrix between the molecule and the point charges on the surface: - EXACT: use exact density, and integrate against the potential of the point charges. This may have inaccuracies when integration points are close to the point charges. - FITPOT: evaluate the molecular potential at the positions of the point charges, and multiply with these charges.

`Charge`

- Type
Block

- Description
Select the algorithm to determine the charges.

`Conv`

- Type
Float

- Default value
1e-08

- Description
Charge convergence threshold in iterative COSMO solution.

`Corr`

- Type
Bool

- Default value
Yes

- GUI name
Correct for outlying charge

- Description
Correct for outlying charge.

`Iter`

- Type
Integer

- Default value
1000

- Description
Maximum number of iterations to solve COSMO equations.

`Method`

- Type
Multiple Choice

- Default value
CONJ

- Options
[CONJ, INVER]

- GUI name
Charge determination method

- Description
INVER: matrix inversion, CONJ: biconjugate gradient method. The CONJ method is guaranteed to converge with small memory requirements and is normally the preferred method.

`Enabled`

- Type
Bool

- Default value
No

- GUI name
Include COSMO solvation

- Description
Use the Conductor like Screening Model (COSMO) to include solvent effects.

`Radii`

- Type
Non-standard block

- Description
The values are the radii of the atomic spheres. If not specified the default values are those by Allinger. Format: ‘AtomType value’. e.g.: ‘H 0.7’

`SCF`

- Type
Multiple Choice

- Default value
VAR

- Options
[VAR, PERT, NONE]

- GUI name
Handle charges

- Description
Determine the point charges either Variational (VAR) or after the SCF as a Perturbation (PERT).

`Solvent`

- Type
Block

- Description
Solvent details

`Del`

- Type
Float

- Description
Del is the value of Klamt’s delta_sol parameter, only relevant in case of Klamt surface.

`Emp`

- Type
Float

- Description
Emp is the empirical scaling factor x for the energy scaling.

`Eps`

- Type
Float

- Description
User-defined dielectric constant of the solvent (overrides the Eps value of the solvent defined in ‘Name’)

`Name`

- Type
Multiple Choice

- Default value
Water

- Options
[AceticAcid, Acetone, Acetonitrile, Ammonia, Aniline, Benzene, BenzylAlcohol, Bromoform, Butanol, isoButanol, tertButanol, CarbonDisulfide, CarbonTetrachloride, Chloroform, Cyclohexane, Cyclohexanone, Dichlorobenzene, DiethylEther, Dioxane, DMFA, DMSO, Ethanol, EthylAcetate, Dichloroethane, EthyleneGlycol, Formamide, FormicAcid, Glycerol, HexamethylPhosphoramide, Hexane, Hydrazine, Methanol, MethylEthylKetone, Dichloromethane, Methylformamide, Methypyrrolidinone, Nitrobenzene, Nitrogen, Nitromethane, PhosphorylChloride, IsoPropanol, Pyridine, Sulfolane, Tetrahydrofuran, Toluene, Triethylamine, TrifluoroaceticAcid, Water]

- GUI name
Solvent

- Description
Name of a pre-defined solvent. A solvent is characterized by the dielectric constant (Eps) and the solvent radius (Rad).

`Rad`

- Type
Float

- Unit
Angstrom

- Description
User-defined radius of the solvent molecule (overrides the Rad value of the solvent defined in ‘Name’).

`Surf`

- Type
Multiple Choice

- Default value
Delley

- Options
[Delley, Wsurf, Asurf, Esurf, Klamt]

- GUI name
Surface type

- Description
Within the COSMO model the molecule is contained in a molecule shaped cavity. Select one of the following surfaces to define the cavity: - Wsurf: Van der Waals surface - Asurf: solvent accessible surface - Esurf: solvent excluding surface - Klamt: Klamt surface - Delley: Delley surface.

`SolvationSM12`

- Type
Block

- Description
Options for Solvation Model 12 (SM12).

`ARO`

- Type
Float

- Default value
0.0

- Description
Square of the fraction of non-hydrogen atoms in the solvent that are aromatic carbon atoms (carbon aromaticity)

`Acid`

- Type
Float

- Default value
0.82

- Description
Abraham hydrogen bond acidity parameter

`Base`

- Type
Float

- Default value
0.35

- Description
Abraham hydrogen bond basicity parameter

`BornC`

- Type
Float

- Default value
3.7

- Description
Coulomb constant for General Born Approximation

`BornRadiusConfig`

- Type
Block

- Description

`MaxCellDistance`

- Type
Float

- Default value
30.0

- Unit
Bohr

- Description
Max distance from the centra cell used when computing the Born radii for periodic systems

`PointsPerBohr`

- Type
Integer

- Default value
10

- Description

`UseLegendreGrid`

- Type
Bool

- Default value
Yes

- Description

`Chgal`

- Type
Float

- Default value
2.474

- Description
Exponential of Pauli’s bond order

`Cust`

- Type
String

- Description
Custom solvent input

`Debug`

- Type
String

- Description
Prints a lot of information about every pass on CDS and ENP code, keywords: ENP, CDS

`EPS`

- Type
Float

- Default value
78.36

- Description
The dielectric constant

`Enabled`

- Type
Bool

- Default value
No

- GUI name
Include SM12 solvation

- Description
Whether to use the Solvation Model 12 (SM12) in the calculation.

`HALO`

- Type
Float

- Default value
0.0

- Description
Square of the fraction of non-hydrogen atoms in the solvent molecule that are F, Cl, or Br (electronegative halogenicity)

`Kappa`

- Type
Float

- Default value
0.0

- Description
Factor for Debye screening

`PostSCF`

- Type
Bool

- Default value
No

- Description
Whether to apply the solvation potential during the SCF or only calculate the solvation energy after the SCF.

`PrintSM12`

- Type
Bool

- Default value
No

- Description
Prints out an in-depth breakdown of solvation energies

`RadSolv`

- Type
Float

- Default value
0.4

- Description
The radius distance between the solute and solvent

`Ref`

- Type
Float

- Default value
1.3328

- Description
Refractive index of solvent

`Solv`

- Type
Multiple Choice

- Default value
WATER

- Options
[ACETICACID, ACETONITRILE, ACETOPHENONE, ANILINE, ANISOLE, BENZENE, BENZONITRILE, BENZYLALCOHOL, BROMOBENZENE, BROMOETHANE, BROMOFORM, BROMOOCTANE, N-BUTANOL, SEC-BUTANOL, BUTANONE, BUTYLACETATE, N-BUTYLBENZENE, SEC-BUTYLBENZENE, T-BUTYLBENZENE, CARBONDISULFIDE, CARBONTETRACHLORIDE, CHLOROBENZENE, CHLOROFORM, CHLOROHEXANE, M-CRESOL, CYCLOHEXANE, CYCLOHEXANONE, DECALIN, DECANE, DECANOL, 1-2-DIBROMOETHANE, DIBUTYLETHER, O-DICHLOROBENZENE, 1-2-DICHLOROETHANE, DIETHYLETHER, DIISOPROPYLETHER, N-N-DIMETHYLACETAMIDE, N-N-DIMETHYLFORMAMIDE, 2-6-DIMETHYLPYRIDINE, DIMETHYLSULFOXIDE, DODECANE, ETHANOL, ETHOXYBENZENE, ETHYLACETATE, ETHYLBENZENE, FLUOROBENZENE, 1-FLUORO-N-OCTANE, HEPTANE, HEPTANOL, HEXADECANE, HEXADECYLIODIDE, HEXANE, HEXANOL, IODOBENZENE, ISOBUTANOL, ISOOCTANE, ISOPROPANOL, ISOPROPYLBENZENE, P-ISOPROPYLTOLUENE, MESITYLENE, METHANOL, METHOXYETHANOL, METHYLENECHLORIDE, N-METHYLFORMAMIDE, 2-METHYLPYRIDINE, 4-METHYL-2-PENTANONE, NITROBENZENE, NITROETHANE, NITROMETHANE, O-NITROTOLUENE, NONANE, NONANOL, OCTANE, OCTANOL, PENTADECANE, PENTANE, PENTANOL, PERFLUOROBENZENE, PHENYLETHER, PROPANOL, PYRIDINE, TETRACHLOROETHENE, TETRAHYDROFURAN, TETRAHYDROTHIOPHENEDIOXIDE, TETRALIN, TOLUENE, TRIBUTYLPHOSPHATE, TRIETHYLAMINE, 1-2-4-TRIMETHYLBENZENE, UNDECANE, WATER, XYLENE, 1-2-DIBROMOETHANE_WATER, 1-2-DICHLOROETHANE_WATER, BENZENE_WATER, CARBONTETRACHLORIDE_WATER, CHLOROBENZENE_WATER, CHLOROFORM_WATER, CYCLOHEXANE_WATER, DIBUTYLETHER_WATER, DIETHYLETHER_WATER, ETHYLACETATE_WATER, HEPTANE_WATER, HEXANE_WATER, NITROBENZENE_WATER, OCTANOL_WATER]

- GUI name
Solvent

- Description
List of predefined solvents

`Tens`

- Type
Float

- Default value
103.62

- Description
Macroscopic surface tension of the solvent at the air/solvent interface at 298K (cal*mol^-1*Ang^-2)

`TopologicalExtrapolation`

- Type
Block

- Description
Method to extrapolate the long range Coulomb potential, needed for periodic calculations

`FirstCell`

- Type
Integer

- Default value
5

- Description
First cell for the topological extrapolation of the long range part of the Coulomb Potential.

`LastCell`

- Type
Integer

- Default value
10

- Description
Last cell for the topological extrapolation of the long range part of the Coulomb Potential.

`Order`

- Type
Integer

- Default value
3

- Description
Order of the topological extrapolation of the long range part of the Coulomb Potential.

`StopAfter`

- Type
String

- Default value
BAND

- Description
Specifies that the program is stopped after execution of a specified program-part (subroutine).

`StoreHamAsMol`

- Type
Bool

- Default value
No

- Description
Undocumented, used for (at least) NEGF.

`StoreHamiltonian`

- Type
Bool

- Description
Undocumented.

`StoreHamiltonian2`

- Type
Bool

- Default value
No

- Description
determine the tight-binding representation of the overlap an fock matrix. Used for (at least) NEGF.

`StrainDerivatives`

- Type
Block

- Description
Undocumented.

`Analytical`

- Type
Bool

- Description
Whether or not to use analytical strain derivatives. By default this is determined automatically, and used if possible.

`AnalyticalElectrostatic`

- Type
Bool

- Default value
No

- Description
Undocumented.

`Analyticalkinetic`

- Type
Bool

- Default value
No

- Description
Undocumented.

`Analyticalpulay`

- Type
Bool

- Default value
No

- Description
Undocumented.

`Analyticalxc`

- Type
Bool

- Default value
No

- Description
Undocumented.

`Celltopoorder`

- Type
Integer

- Default value
20

- Description
Undocumented.

`Coreorthoption`

- Type
Integer

- Default value
2

- Description
Undocumented.

`Fitrho0numintextrarad`

- Type
Integer

- Default value
0

- Description
Undocumented.

`Fitrho0prune`

- Type
Bool

- Default value
Yes

- Description
Undocumented.

`Kinviadagger`

- Type
Bool

- Default value
No

- Description
Undocumented.

`Lmaxmultipoleexpansion`

- Type
Integer

- Default value
4

- Description
Undocumented.

`Naiveelstat`

- Type
Bool

- Default value
No

- Description
Undocumented.

`Numericaldefdef`

- Type
Bool

- Default value
Yes

- Description
Undocumented.

`Numericaldefdeflong`

- Type
Bool

- Default value
No

- Description
Undocumented.

`Pairgridlowerangularorder`

- Type
Integer

- Default value
5

- Description
Undocumented.

`Pairgridradpointsincrease`

- Type
Integer

- Default value
0

- Description
Undocumented.

`Renormalizechargefitrho0`

- Type
Bool

- Default value
No

- Description
Undocumented.

`Shiftmultipoleorigin`

- Type
Bool

- Default value
Yes

- Description
Undocumented.

`Skipinlgwsmodule`

- Type
Bool

- Default value
Yes

- Description
Undocumented.

`SubtractAtomicXC`

- Type
Bool

- Default value
Yes

- Description
Derive stress from xc energy difference of molecule versus atoms.

`Usesymmetry`

- Type
Bool

- Default value
No

- Description
Undocumented.

`Usevstrainderrho`

- Type
Bool

- Default value
No

- Description
Undocumented.

`fitrho0numintextral`

- Type
Integer

- Default value
0

- Description
Undocumented.

`SubSymmetry`

- Type
Integer List

- Description
The indices of the symmetry operators to maintain.

`Tails`

- Type
Block

- Description
Ignore function tails.

`Bas`

- Type
Float

- Default value
1e-06

- GUI name
Basis functions

- Description
Cut off the basis functions when smaller than the specified threshold.

`Title`

- Type
String

- Default value
- Description
Title of the calculation, which will be printed in the output file.

`Unrestricted`

- Type
Bool

- Default value
No

- Description
Controls whether Band should perform a spin-unrestricted calculation. Spin-unrestricted calculations are computationally roughly twice as expensive as spin-restricted.

`UnrestrictedOnlyReference`

- Type
Bool

- Default value
No

- Description
Undocumented.

`UnrestrictedReference`

- Type
Bool

- Default value
No

- Description
Undocumented.

`UnrestrictedStartup`

- Type
Bool

- Default value
No

- Description
Undocumented.

`UseInversionSymmetryInReciprocalSpace`

- Type
Bool

- Default value
Yes

- Description
Whether to use inversion symmetry in reciprocal space. This is almost always a valid assumption.

`UseSymmetry`

- Type
Bool

- Default value
Yes

- Description
Whether or not to exploit symmetry during the calculation.

`XC`

- Type
Block

- Description
Exchange Correlation functionals

`DFTHalf`

- Type
Block

- Description
DFT-1/2 method for band gaps. See PRB vol 78,125116 2008. This method can be used in combination with any functional. For each active atom type (see ActiveAtomType) Band will perform SCF calculations at different screening cut-off values (see ScreeningCutOffs) and pick the cut-off value that maximizes the band gap. If multiple atom types are active, the screening cut-off optimizations are done one type at the time (in the same order as the ActiveAtomType blocks appear in the input).

`ActiveAtomType`

- Type
Block

- Recurring
True

- Description
Use the DFT-1/2 method for the atom-type specified in this block.

`AtomType`

- Type
String

- Description
Atom-type to use. You can activate all atom-types by specifying ‘All’.

`IonicCharge`

- Type
Float

- Default value
0.5

- Description
The amount of charge to be removed from the atomic HOMO.

`ScreeningCutOffs`

- Type
Float List

- Default value
[0.0, 1.0, 2.0, 3.0, 4.0, 5.0]

- Unit
Bohr

- Description
List of screening cut-offs (to screen the asymptotic IonicCharge/r potential). Band will loop over these values and find the cut-off that maximizes the band-gap. If only one number is provided, Band will simply use that value.

`Enabled`

- Type
Bool

- Default value
No

- GUI name
Use method

- Description
Whether the DFT-1/2 method will be used.

`Prepare`

- Type
Bool

- Default value
No

- Description
Analyze the band structure to determine reasonable settings for an DFT-1/2 calculation. If this is possible the list of active atom types is written to the output. This can be used in a next run as the values for ActiveAtomType. The DFTHalf%Enabled key should be set to false

`SelfConsistent`

- Type
Bool

- Default value
Yes

- Description
Apply the extra potential during the SCF, or only afterwards. Applying DFT-1/2 only post SCF increases the band gap, compared to the self-consistent one.

`DoubleHybrid`

- Type
String

- Description
Specifies the double hybrid functional that should be used during the SCF.

`EmpiricalScaling`

- Type
Multiple Choice

- Default value
None

- Options
[None, SOS, SCS, SCSMI]

- Description
Calculate the (SOS/SCS/SCSMI)-MP2 correlation energy.

`GLLBKParameter`

- Type
Float

- Default value
0.382

- Description
K parameter for the GLLB functionals. See equation (20) of the paper.

`HartreeFock`

- Type
Bool

- Default value
No

- Description
Stand alone HF calculation.

`MP2`

- Type
Bool

- Default value
No

- Description
Calculate the MP2 correlation energy after the HF SCF is completed.

`RPA`

- Type
Multiple Choice

- Default value
None

- Options
[None, Direct, Sigma, SOSEX, SOSSX]

- Description
Specifies that RPA is used an possibly also a post-RPA method. By default, direct RPA is used

`diracgga`

- Type
String

- Default value
- Description
GGA for the dirac .

`dispersion`

- Type
String

- Default value
DEFAULT

- Description
The dispersion correction model to be used.

`gga`

- Type
String

- Default value
NONE

- Description
GGA XC functional.

`lda`

- Type
String

- Default value
VWN

- Description
LDA XC functional.

`libxc`

- Type
String

- Default value
NONE

- Description
Functional using the LicXC library.

`libxcdensitythreshold`

- Type
Float

- Default value
1e-10

- Description
Density threshold for LibXC functionals.

`metagga`

- Type
String

- Default value
NONE

- Description
MetaGG XC functional.

`model`

- Type
String

- Default value
LB94

- Description
Model potential. The possible choices are LB94, GLLB-SC, BGLLB-VWN, and BGLLB-LYP

`spinorbitmagnetization`

- Type
String

- Default value
collinearz

- Description
Type of Spin-Orbit magnetization.

`tb_mbjafactor`

- Type
Float

- Default value
-1.23456789

- Description
a parameter for the TB-MBJ model potential.

`tb_mbjbfactor`

- Type
Float

- Default value
-1.23456789

- Description
b parameter for the TB-MBJ model potential..

`tb_mbjcfactor`

- Type
Float

- Default value
-1.23456789

- Description
c parameter for the TB-MBJ model potential..

`tb_mbjefactor`

- Type
Float

- Default value
-1.23456789

- Description
e parameter for the TB-MBJ model potential..

`usexcfun`

- Type
Bool

- Default value
No

- Description
Whether ot not the XCFun library should be used.

`xcfun`

- Type
Bool

- Default value
No

- Description
Functional for the XCFun library.

`ZlmFit`

- Type
Block

- Description
Options for the density fitting scheme ‘ZlmFit’.

`AllowBoost`

- Type
Bool

- Default value
Yes

- Description
Allow automatic atom-dependent tuning of maximum l of spherical harmonics expansion. Whether or not this boost is needed for a given atom is based on an heuristic estimate of how complex the density around that atom is.

`DensityThreshold`

- Type
Float

- Description
Threshold below which the electron density is considered to be negligible. Depends on Quality and is normally 1.0e-7

`FGaussianW`

- Type
Float

- Default value
1.0

- Description
Only for 3D periodic systems. Width of the Gaussian functions replacing the S and P Zlms for Fourier transform.

`FGridSpacing`

- Type
Float

- Description
Only for 3D periodic systems. Spacing for the Fourier grid. By default, this depends on the quality.

`FKSpaceCutOff`

- Type
Float

- Description
Only for 3D periodic systems. Cut-off of the grid in k-space for the Fourier transform.

`FirstTopoCell`

- Type
Integer

- Default value
5

- Description
First cell for the topological extrapolation of the long range part of the Coulomb Potential.

`LMargin`

- Type
Integer

- Description
User-defined l-margin, i.e., l_max for fitting is max(lMargin + l_max_basis_function, 2*l_max_basis_function). Depends on Quality and normally is 4

`LastTopoCell`

- Type
Integer

- Default value
10

- Description
Last cell for the topological extrapolation of the long range part of the Coulomb Potential.

`NumStarsPartitionFun`

- Type
Integer

- Default value
5

- Description
Number of cell stars to consider when computing the partition function.

`OrderTopoTrick`

- Type
Integer

- Default value
3

- Description
Order of the topological extrapolation of the long range part of the Coulomb Potential.

`PartitionFunThreshold`

- Type
Float

- Default value
0.0

- Description
Threshold for the partition functions: if an integration point has a partition function weight smaller than this threshold, it will be discarded.

`Quality`

- Type
Multiple Choice

- Default value
Auto

- Options
[Auto, Basic, Normal, Good, VeryGood, Excellent]

- GUI name
Spline Zlm fit

- Description
Quality of the density-fitting approximation. For a description of the various qualities and the associated numerical accuracy see reference. If ‘Auto’, the quality defined in the ‘NumericalQuality’ will be used.

`QualityPerRegion`

- Type
Block

- Recurring
True

- Description
Sets the ZlmFit quality for all atoms in a region. If specified, this overwrites the globally set quality.

`Quality`

- Type
Multiple Choice

- Options
[Basic, Normal, Good, VeryGood, Excellent]

- Description
The region’s quality of the ZlmFit.

`Region`

- Type
String

- Description
The identifier of the region for which to set the quality.

### conductance¶

`EnergyGrid`

- Type
Block

- Description
Energy grid for Transmission Function

`Max`

- Type
Float

- Default value
5.0

- Unit
eV

- Description
Max Energy (relative to Fermi energy)

`Min`

- Type
Float

- Default value
-5.0

- Unit
eV

- Description
Min energy (relative to Fermi energy)

`Num`

- Type
Integer

- Default value
200

- Description
Number of energy values in which the interval Min-Max is subdivided

`Files`

- Type
Block

- Description
path of files

`HamiltonianElectrode`

- Type
String

- Default value
- Description

`HamiltonianMolecule`

- Type
String

- Default value
- Description

`Leads`

- Type
String

- Default value
- Description
Path (either absolute or relative) of the lead results file

`OverlapElectrode`

- Type
String

- Default value
- Description

`OverlapMolecule`

- Type
String

- Default value
- Description

`Scattering`

- Type
String

- Default value
- Description
Path (either absolute or relative) of the scattering region results

`Output`

- Type
Block

- Description
options describing what should be printed

`OldOutput`

- Type
Bool

- Default value
No

- Description

`Physics`

- Type
Block

- Description
Block describing the physics of the system

`FermiEnergy`

- Type
Block

- Description
Block describing the physics of the system

`Electrode`

- Type
Float

- Default value
0.0

- Description
Fermi energy of the electrode

`Technical`

- Type
Block

- Description
options describing technical parts of the calculation

`Eta`

- Type
Float

- Default value
1e-05

- Description
To avoid poles of the Green’s function, a small imaginary number is added to the energy

`overwriteLeads`

- Type
Bool

- Default value
Yes

- Description
If true, Hamiltonians H_L and H_R are taken from the DFTB-leads calculation. If False, they are taken from the DFTB scattering-region calculation

`setOffDiagonalToZero`

- Type
Bool

- Default value
Yes

- Description
If true, H_LR and S_LR are explicitly set to zero. If False, they are taken from the DFTB scattering-region calculation.

### sgf¶

`Debug`

- Type
String

- Recurring
True

- Description

`Save`

- Type
String

- Recurring
True

- Description

`SurfaceGF`

- Type
Block

- Description

`BANDMU`

- Type
Float

- Default value
0.0

- Description

`CONTACT`

- Type
Integer

- Default value
1

- Description

`CPMARGIN`

- Type
Float

- Description

`ContourQuality`

- Type
Multiple Choice

- Default value
good

- Options
[basic, normal, good, verygood, excellent]

- Description

`DELTA`

- Type
Float

- Description

`ETA`

- Type
Float

- Default value
1e-05

- Description

`KGRID`

- Type
Integer

- Description

`KT`

- Type
Float

- Description

`MAXDOS`

- Type
Float

- Description

`MINDOS`

- Type
Float

- Description

`MINVALENCE`

- Type
Float

- Description

`MULOWER`

- Type
Float

- Description

`MUUPPER`

- Type
Float

- Description

`NARCPTS`

- Type
Integer

- Description

`NDOSPTS`

- Type
Integer

- Description

`NE`

- Type
Integer

- Description

`NEQLINEPTS`

- Type
Integer

- Description

`NFPOLES`

- Type
Integer

- Description

`NLAYERS`

- Type
Integer

- Description

`NNONEQLPTS`

- Type
Integer

- Description

`PHI1`

- Type
Float

- Default value
0.0

- Description

`PHI2`

- Type
Float

- Default value
0.0

- Description

`RKFFileName`

- Type
String

- Default value
RUNKF

- Description

`SCMCODE`

- Type
Bool

- Default value
No

- Description

`SECANT`

- Type
Bool

- Default value
No

- Description

`SGFMaxIter`

- Type
Integer

- Default value
500

- Description

`SGFTOL`

- Type
Float

- Default value
1e-08

- Description

`TOL`

- Type
Float

- Default value
0.0001

- Description

`TRANSDIR`

- Type
Integer

- Default value
1

- Description

`TRUEMU`

- Type
Float

- Default value
0.0

- Description

`deContourInt`

- Type
Float

- Default value
-1.0

- Description

`TightBinding`

- Type
Block

- Description

`DTol`

- Type
Float

- Default value
0.001

- Description

`Eps`

- Type
Float

- Default value
1e-18

- Description

`IODim`

- Type
Integer

- Description

`MaxMerit`

- Type
Float

- Description

`MaxRange`

- Type
Float

- Description

`XTol`

- Type
Float

- Default value
5e-06

- Description

`Title`

- Type
String

- Description