# Keywords¶

## Links to manual entries¶

## Summary of all keywords¶

`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: False 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: False 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 `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: True 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 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: False 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 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 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: True 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: True 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 `ByAtomType`

Type: Non-standard block Description: Definition of the basis set for specific atom types (one definition per line). Format: ‘AtomType Type=Type Core=Core’. Example: ‘C.large_basis Type=TZ2P Core=None’ `Core`

Type: Multiple Choice Default value: Large Options: [None, Small, Medium, Large] Description: Size of the frozen core. `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’ `Type`

Type: Multiple Choice Default value: DZ Options: [SZ, DZ, DZP, TZP, TZ2P, QZ4P] Description: The basis sets to 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. `AtomDepQuality`

Type: Non-standard block Description: One can define a different grid quality for each atom (one definition per line). Line format: ‘AtomIndex Quality’, e.g. ‘3 Good’ means that a grid of Good quality will be used for the third atom in input order. If the index of an atom is not present in the AtomDepQuality section, the quality defined in the Quality key will be used `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. `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.

`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: False Description: Use an atomic dipole as magnetic field instead of a uniform magnetic field. `DipoleAtom`

Type: Integer Default value: 1 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. `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: a.u. Description: Simulates a finite-temperature electronic distribution using the defined energy. This may be used to achieve convergence in an otherwise problematically converging system. The energy of a finite-T distribution is different from the T=0 value, but for small T a fair approximation of the zero-T energy is obtained by extrapolation. The extrapolation energy correction term is printed with the survey of the bonding energy in the output file. Check that this value is not too large. Build experience yourself how different settings may affect the outcomes. Note: this key is meant to help you overcome convergence problems, not to do finite-temperature research! Only the electronic distribution is computed T-dependent, other aspects are not accounted for! `InitialDensity`

Type: Multiple Choice Default value: rho Options: [rho, psi] 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: False 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. `NoDegenerate`

Type: Bool Default value: False Description: This key prevents any internal automatic setting of the key DEGENERATE. `SpinFlip`

Type: String Default value: 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. `startwithmaxspin`

Type: Bool Default value: True 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.

`CPVector`

Type: Integer Default value: 128 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 `Basis`

Type: Float Default value: 1e-08 Description: Criteria for linear dependency of the basis: smallest eigenvalue of the overlap matrix of normalized Bloch functions. `Core`

Type: Float Default value: 0.98 Description: The program verifies that the frozen core approximation is reasonable, by checking the smallest value of the overlap matrix of the core (Bloch) orbitals against 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: True Description: Change automatically the value of dimix during the SCF. `CHuge`

Type: Float Default value: 20.0 Description: When the largest coefficient in the DIIS expansion exceeds this value, damping is applied `CLarge`

Type: Float Default value: 20.0 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 Description: Mixing parameter for the DIIS procedure `NCycleDamp`

Type: Integer Default value: 1 Description: Number of initial iterations where damping is applied, before any DIIS is considered `NVctrx`

Type: Integer Default value: 20 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 `DeltaE`

Type: Float Default value: 0.005 Unit: Hartree 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. `Enabled`

Type: Bool Default value: False Description: Whether or not to calculate the density of states. `Energies`

Type: Integer Description: Number of equidistant energy-values for the DOS grid. This keyword supersedes 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: True 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: False Description: Calculate the COOP (crystal orbital overlap population).

`DosBas`

Type: Non-standard block Description: Used to specify the fragment basis for the DOS. `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: False Description: Compute the EffectiveMass. `KPointCoord`

Type: Float List Unit: 1/Bohr Recurring: True Description: Coordinate of the k-points for which you would like to compute the effective mass. `NumAbove`

Type: Integer Default value: 1 Description: Number of bands to take into account above the Fermi level. `NumBelow`

Type: Integer Default value: 1 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: False Description: Compute the EFG tensor (for nuclear quadrupole interaction).

`EField`

Type: Block Description: Include a homogeneous, static, electric field in the z-direction (only possible for 0D, 1D or 2D periodic systems) `Ez`

Type: Float Default value: 0.0 Description: Strength of the electric field, in units as selected with the EField unit key. `unit`

Type: Multiple Choice Default value: Volt/Angstrom Options: [Volt/Angstrom, a.u., Volt/Bohr, Volt/meter] Description: Unit of the electric field Ez

`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 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: False 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’

`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.

`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. `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: Once can define the regular grid specification in this block. See example.

`GridBasedAIM`

Type: Block Description: Invoke the ultra fast grid based Bader analysis. `Enabled`

Type: Bool Default value: False 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: False 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. `HubbardU`

Type: Block Description: Options for Hubbard-corrected DFT calculations. `Enabled`

Type: Bool Default value: False Description: Whether or not to apply the Hubbard Hamiltonian `LValue`

Type: String Default value: Description: For each atom type specify the l value (0 - s orbitals, 1 - p orbitals, 2 - d orbitals). A negative value is interpreted as no l-value. `PrintOccupations`

Type: Bool Default value: True Description: Whether or not to print the occupations during the SCF. `UValue`

Type: String Default value: Description: For each atom type specify the U value (in atomic units). A value of 0.0 is interpreted as no U.

`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 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] 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 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] 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.

`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: False Description: Compute NMR shielding.

`MultiSecantConfig`

Type: Block Description: Parameters for the Multi-secant SCF convergence method. `CMax`

Type: Float Default value: 20.0 Description: Maximum coefficient allowed in expansion `InitialSigmaN`

Type: Float Default value: 0.1 Description: This is a lot like a mix factor: bigger means bolder `MaxSigmaN`

Type: Float Default value: 0.3 Description: Upper bound for the SigmaN parameter `MaxVectors`

Type: Integer Default value: 20 Description: Maximum number of previous cycles to be used `MinSigmaN`

Type: Float Default value: 0.01 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: True 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: True Description: Apply the smaller alignment shift. This requires an extra alignment run. Usually this shift is smaller. `AutoContour`

Type: Bool Default value: True 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: False 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: False 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: True Description: Whether or not to ignore the outer layer. `KT`

Type: Float Default value: 0.001 Description: k-Boltzman 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.

`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 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 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 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: True 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: False 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: Bool Default value: True Description: In case the DIIS method is not working, one can switch to plain mixing by setting DIIS to false. `LowFreqAlgo`

Type: Bool Default value: True 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 algoritm 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!`Mixing`

Type: Float Default value: 0.2 Description: Mixing value for the SCF optimization. `NCycle`

Type: Integer Default value: 20 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: True Description: Undocumented. `Enabled`

Type: Bool Default value: False 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: False Description: Undocumented. `Original`

Type: Bool Default value: False Description: Undocumented. `Print_jp`

Type: Bool Description: Print paramagnetic current. `SuperCell`

Type: Bool Default value: True 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: True 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: False 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: False 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. `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: False 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 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: False 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: False 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: True 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. `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. `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

`Relativity`

Type: Block Description: Options for relativistic effects. `Level`

Type: Multiple Choice Default value: None Options: [None, Scalar, Spin-Orbit] 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. `DensityPlot`

Type: Bool Default value: False Description: Goes together with the DensityPlot block and Grid blocks `File`

Type: String Default value: Description: Name of the restart file. `NOCVOrbitalPlot`

Type: Bool Default value: False Description: Goes together with the NOCVOrbitalPlot and Grid blocks. `NOCVdRhoPlot`

Type: Bool Default value: False Description: Goes together with the NOCVdRhoPlot and Grid blocks. `OrbitalPlot`

Type: Bool Default value: False Description: Goes together with the OrbitalPlot and Grid `ResponseInducedDensityPlot`

Type: Bool Default value: False Description: Goes together with the ResponseInducedDensityPlot and Grid blocks. `SCF`

Type: Bool Default value: False Description: Continue the SCF procedure using the orbital coefficients and occupations from the restart file. `UseDensityMatrix`

Type: Bool Default value: False 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.

`RIHartreeFock`

Type: Block Description: The Hartree-Fock exchange matrix is calculated through a procedure known as Resolution of the Identity (RI). Here you can tweak various parameters of the procedure. `AtomDepQuality`

Type: Non-standard block Description: One can define a different fit-set quality for each atom. The syntax for this free block is ‘iAtom quality’, where iAtom is the index of the atom in input order. `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 the SCF does not converge or you obtain unphysically large bond energy in an Hybrid calculation, you might try setting the DependencyThreshold to a larger value (e.g. 3.0E-3). `FitSetQuality`

Type: Multiple Choice Default value: Normal Options: [VeryBasic, Basic, Normal, Good, VeryGood, Excellent] Description: The auxiliary fit set employed in the RI scheme. This is an important aspect of the procedure, significantly affecting both accuracy and computation time. For SZ and DZ basis set a ‘basic’ FitSetQuality will suffice. For ‘DZP’ and ‘TZP’ a normal quality is recommended. For larger basis set, use either ‘normal’ or better FitSetQuality. `Quality`

Type: Multiple Choice Default value: Normal Options: [VeryBasic, Basic, Normal, Good, VeryGood, Excellent] Description: Accuracy of numerical integration and thresholds of the RI procedure.

`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 Description: The maximum number of SCF iterations to be performed. `Method`

Type: Multiple Choice Default value: DIIS Options: [DIIS, MultiSecant] 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. `PMatrix`

Type: Bool Description: If present, evaluate the charge density from the P-matrix. See also the key Eigenstates. `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 `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: Explicitely 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] 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: Explicitely 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] 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: True 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] 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: False 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 Allinge. Format: ‘AtomType value’. e.g.: ‘H 0.7’ `SCF`

Type: Multiple Choice Default value: VAR Options: [VAR, PERT, NONE] 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] 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] 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 bacicity 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: True 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: False 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: False Description: Whether to apply the solvation potential during the SCF or only calculate the solvation energy after the SCF. `PrintSM12`

Type: Bool Default value: False 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] 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: False Description: Undocumented, used for (at least) NEGF. `StoreHamiltonian`

Type: Bool Description: Undocumented. `StoreHamiltonian2`

Type: Bool Default value: False 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: False Description: Undocumented. `Analyticalkinetic`

Type: Bool Default value: False Description: Undocumented. `Analyticalpulay`

Type: Bool Default value: False Description: Undocumented. `Analyticalxc`

Type: Bool Default value: False Description: Undocumented. `Cellpartitiondelta`

Type: Float Default value: 4.0 Description: Undocumented. `Cellpartitioninterpolationcubic`

Type: Bool Default value: False Description: Undocumented. `Cellpartitioninterpolationmesh`

Type: Integer Default value: 100 Description: Undocumented. `Cellpartitionversion`

Type: Integer Default value: 2 Description: Undocumented. `Celltopoorder`

Type: Integer Default value: 20 Description: Undocumented. `Centralizenaturallsg`

Type: Bool Default value: False Description: Undocumented. `Coreorthoption`

Type: Integer Default value: 2 Description: Undocumented. `Fitrho0numintextrarad`

Type: Integer Default value: 0 Description: Undocumented. `Fitrho0prune`

Type: Bool Default value: True Description: Undocumented. `Interpolatecellpartition`

Type: Bool Default value: False Description: Undocumented. `Kinviadagger`

Type: Bool Default value: False Description: Undocumented. `Lmaxmultipoleexpansion`

Type: Integer Default value: 4 Description: Undocumented. `Naiveelstat`

Type: Bool Default value: False Description: Undocumented. `Numericaldefdef`

Type: Bool Default value: True Description: Undocumented. `Numericaldefdeflong`

Type: Bool Default value: False Description: Undocumented. `Numintextral`

Type: Integer Default value: 0 Description: Undocumented. `Numintextrarad`

Type: Integer Default value: 0 Description: Undocumented. `Pairgridlowerangularorder`

Type: Integer Default value: 5 Description: Undocumented. `Pairgridradpointsincrease`

Type: Integer Default value: 0 Description: Undocumented. `Partitionfunctiontol`

Type: Float Default value: 1e-08 Description: Undocumented. `Prunelatticesummedgrid`

Type: Bool Default value: True Description: Undocumented. `Reduceaccuracylsg`

Type: Bool Default value: False Description: Undocumented. `Renormalizechargefitrho0`

Type: Bool Default value: False Description: Undocumented. `Shiftmultipoleorigin`

Type: Bool Default value: True Description: Undocumented. `Simplelatticesummedgrid`

Type: Bool Default value: False Description: Undocumented. `Skipinlgwsmodule`

Type: Bool Default value: True Description: Undocumented. `Subtractatomicxc`

Type: Bool Default value: False Description: Undocumented. `Usesymmetry`

Type: Bool Default value: False Description: Undocumented. `Usevstrainderrho`

Type: Bool Default value: False Description: Undocumented. `atomradiuslsg`

Type: Float Default value: 0.0 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 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: False Description: Controls wheather Band should perform a spin-unrestricted calculation. Spin-unrestricted calculations are computationally roughly twice as expensive as spin-restricted. `UnrestrictedOnlyReference`

Type: Bool Default value: False Description: Undocumented. `UnrestrictedReference`

Type: Bool Default value: False Description: Undocumented. `UnrestrictedStartup`

Type: Bool Default value: False Description: Undocumented. `UseSymmetry`

Type: Bool Default value: True 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: False Description: Whether the DFT-1/2 method will be used. `Prepare`

Type: Bool Default value: False 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: True 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.

`GLLBKParameter`

Type: Float Default value: 0.382 Description: K parameter for the GLLB functionals. See equation (20) of the paper. `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: False Description: Whether ot not the XCFun library should be used. `xcfun`

Type: Bool Default value: False Description: Functional for the XCFun library.

`ZlmFit`

Type: Block Description: Options for the density fitting scheme ‘ZlmFit’. `AllowBoost`

Type: Bool Default value: True 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. `AtomDepQuality`

Type: Non-standard block Description: One can specify different ZlmFit-quality for different atoms, The syntax for this free block is ‘iAtom quality’, where iAtom is the index of the atom in input order. For the atoms that are not present in the AtomDepQuality sub-block, the quality defined in the Quality key will be used. `DensityThreshold`

Type: Float Default value: 1e-07 Description: Threshold below which the electron density is considered to be negligible. `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 Default value: 4 Description: User-defined l-margin, i.e., l_max for fitting is max(lMargin + l_max_basis_function, 2*l_max_basis_function) `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] 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.