MLPotential Keywords

Engine MLPotential

AIMNet2
Type:

Block

Recurring:

False

Description:

Options for the AIMNet2 machine learning potential backend.

CompileModel
Type:

Bool

Default value:

No

Description:

Compile the AIMNet2 model. This can improve performance for repeated calculations (e.g. during molecular dynamics), but increases startup cost.

EnsembleSize
Type:

Integer

Default value:

4

Value Range:

2 <= value <= 4

Description:

Number of members in the ensemble. Uncertainty estimates improve with the number of members, but computational cost scales linearly.

LongRange
Type:

Block

Recurring:

False

Description:

Long-range electrostatics options.

DSF
Type:

Block

Recurring:

False

Description:

Damped shifted force Coulomb settings.

Alpha
Type:

Float

Default value:

0.2

Value Range:

value > 0

Description:

Damping parameter for the DSF Coulomb method.

Cutoff
Type:

Float

Default value:

15.0

Unit:

Angstrom

Value Range:

value > 0

Description:

Cutoff distance in Angstrom for the DSF Coulomb neighbor list.

Ewald
Type:

Block

Recurring:

False

Description:

Accuracy settings for Ewald and PME Coulomb summation.

Accuracy
Type:

Float

Default value:

1e-06

Value Range:

value > 0

Description:

Target accuracy for Ewald and PME summation. Smaller values are more accurate and more expensive.

Type
Type:

Multiple Choice

Default value:

Auto

Options:

[Auto, Simple, DSF, Ewald, PME]

Description:

Long-range Coulomb method. Auto uses the AIMNet2 model default (typically simple for aperiodic systems, DSF for periodic systems). Simple uses all-pairs pairwise Coulomb, and is suitable for small aperiodic systems. DSF (damped shifted force) Coulomb with a finite cutoff is an efficient method for periodic and large aperiodic systems. Ewald and PME (Particle mesh Ewald) is for high accuracy periodic electrostatics.

UseEnsemble
Type:

Bool

Default value:

No

Description:

Whether to use an ensemble of independently trained model members for calculations. This gives uncertainty estimates for energies and forces, but at increased computational cost.

Backend
Type:

Multiple Choice

Options:

[AIMNet2, FAIRChem, M3GNet, MACE, MatGL, NEP, TorchANI]

Description:

The machine learning potential backend.

Device
Type:

Multiple Choice

Default value:

Options:

[, cpu, cuda:0, cuda:1]

Description:

Device on which to run the calculation (e.g. cpu, cuda:0).

If empty, the device can be controlled using environment variables for TensorFlow or PyTorch.

FAIRChem
Type:

Block

Recurring:

False

Description:

Options for the FAIRChem machine learning potential backend.

ModelTask
Type:

String

Default value:

Description:

Model task to use if a custom UMA/eSEN model is supplied via a parameter file (e.g. ‘OC20’, ‘OC22’, ‘OC25’, ‘ODAC’, ‘OMat’, ‘OMC’, ‘OMol’). Ignored if a specific FAIRChem model is selected.

Fukui
Type:

Block

Recurring:

False

Description:

Expert settings for the charged states used to calculate Fukui functions and vertical ionization properties when AMS Properties%Other is requested.

Enabled
Type:

Multiple Choice

Default value:

Auto

Options:

[Auto, Yes, No]

Description:

Controls calculation of the Fukui analysis when AMS Properties%Other is requested. Auto calculates it for supported aperiodic models, Yes explicitly requests it and reports a warning when it is unavailable, and No disables it.

FMinus
Type:

Block

Recurring:

False

Description:

Settings for the electron-removed state used to calculate Fukui f- and the vertical ionization energy.

ChargeDelta
Type:

Integer

Default value:

1

Value Range:

value > 0

Description:

Change in total charge relative to the reference system. A value of 1 corresponds to removing one electron.

SpinState
Type:

Multiple Choice

Default value:

Auto

Options:

[Auto, Low, High, UnpairedElectrons]

Description:

Spin state of the electron-removed system. Auto currently selects the lowest spin compatible with the reference spin and charge change. Low and High explicitly select the lowest or highest directly reachable spin, respectively. UnpairedElectrons uses the value of the UnpairedElectrons keyword.

UnpairedElectrons
Type:

Integer

Default value:

0

Value Range:

value >= 0

Description:

Number of unpaired electrons in the electron-removed state. This value is used only when SpinState is UnpairedElectrons.

FPlus
Type:

Block

Recurring:

False

Description:

Settings for the electron-added state used to calculate Fukui f+ and the vertical electron affinity.

ChargeDelta
Type:

Integer

Default value:

-1

Value Range:

value < 0

Description:

Change in total charge relative to the reference system. A value of -1 corresponds to adding one electron.

SpinState
Type:

Multiple Choice

Default value:

Auto

Options:

[Auto, Low, High, UnpairedElectrons]

Description:

Spin state of the electron-added system. Auto currently selects the lowest spin compatible with the reference spin and charge change. Low and High explicitly select the lowest or highest directly reachable spin, respectively. UnpairedElectrons uses the value of the UnpairedElectrons keyword.

UnpairedElectrons
Type:

Integer

Default value:

0

Value Range:

value >= 0

Description:

Number of unpaired electrons in the electron-added state. This value is used only when SpinState is UnpairedElectrons.

MACE
Type:

Block

Recurring:

False

Description:

Options for the MACE machine learning potential backend.

DataType
Type:

Multiple Choice

Default value:

float32

Options:

[float32, float64]

Description:

Using float32 is faster but less accurate, and generally recommended for MD. Conversely using float64 is slower but more accurate, and recommended for geometry optimization.

EnableCuEquivariance
Type:

Bool

Default value:

Yes

Description:

Enable CUDA-accelerated cuEquivariance library for equivariant neural networks, if CUDA available.

ModelHead
Type:

String

Default value:

Description:

Model head to use if a custom MACE model is supplied via a parameter file (e.g. ‘omat_pbe’, ‘omol’, ‘spice_wB97M’, ‘ωB97M-D3(BJ)’, ‘rgd1_b3lyp’, ‘oc20_usemppbe’, ‘matpes_r2scan’). Ignored if a specific MACE model is selected.

MLDistanceUnit
Type:

Multiple Choice

Default value:

Auto

Options:

[Auto, angstrom, bohr]

GUI name:

Internal distance unit

Description:

Unit of distances expected by the ML backend (not the ASE calculator). The ASE calculator may require this information.

MLEnergyUnit
Type:

Multiple Choice

Default value:

Auto

Options:

[Auto, Hartree, eV, kcal/mol, kJ/mol]

GUI name:

Internal energy unit

Description:

Unit of energy output by the ML backend (not the unit output by the ASE calculator). The ASE calculator may require this information.

Model
Type:

Multiple Choice

Default value:

ANI-2x

Options:

[Custom, AIMNet2-B973c, AIMNet2-NSE, AIMNet2-Pd, AIMNet2-Rxn, AIMNet2-wB97MD3, ANI-1ccx, ANI-1x, ANI-2x, eSEN-S-Con-OMol, M3GNet-UP-2022, MACE-MP-0-Large, MACE-MP-0-Medium, MACE-MP-0-Small, MACE-MPA-0, NEP89, QET-MatQ, QET-PBE-2025, QET-r2SCAN-2025, TensorNet-PBE-M-2025, TensorNet-r2SCAN-M-2025, UMA-S-1.2-OC20, UMA-S-1.2-OC22, UMA-S-1.2-OC25, UMA-S-1.2-ODAC, UMA-S-1.2-OMat, UMA-S-1.2-OMC, UMA-S-1.2-OMol]

Description:

Select a pre-parameterized or custom model.

AIMNet2 variants: best for fast calculations of small, drug-like molecules; limited to systems of 14 elements (H, B, C, N, O, F, Si, P, S, Cl, As/Pd, Se, Br, I).

ANI-(1x/1ccx/2x): best for very fast calculations of organic molecules; limited to elements H, C, N, O (ANI-1x/1ccx), F, S, Cl (ANI-2x).

eSEN-S-Con-OMol: best for highly accurate calculations of diverse organic and bio-relevant molecules; not intended for calculations on periodic inorganic bulk materials.

M3GNet-UP-2022: best for fast calculations of inorganic crystalline materials; not designed for accurately modeling small organic molecules or biomolecules.

MACE-MP-0-(Small/Medium/Large): best for accurate periodic calculations of inorganic materials; size trades speed/accuracy; not designed for accurately modeling small organic molecules or biomolecules. MACE-MPA-0 has improved accuracy vs MP-0.

QET-MatQ, QET-PBE-2025, QET-r2SCAN-2025: best for charge-aware calculations of inorganic materials, ionic systems, electrolytes, and interfaces.

TensorNet-PBE-M-2025, TensorNet-r2SCAN-M-2025: best for efficient calculations of inorganic materials.

NEP89: Neuroevolution potential for neutral systems.

UMA-S-1.2 variants: best for high accuracy calculations on a broad range of systems; choose from OC20 (adsorption and surface chemistry), OC22 (oxide catalysis), OC25 (electrocatalysis), ODAC (adsorption in porous frameworks), OMat (inorganic materials), OMC (organic molecular crystals), OMol (molecules, biomolecules, metal complexes, electrolytes); can be computationally expensive compared to other, more targeted models.

Set Custom to choose a backend and provide your own parameters.

NumThreads
Type:

String

Default value:

GUI name:

Number of threads

Description:

Number of threads.

If not empty, OMP_NUM_THREADS will be set to this number; for PyTorch-engines, torch.set_num_threads() will be called.

ParameterDir
Type:

String

Default value:

GUI name:

Parameter directory

Description:

Path to a set of parameters for the backend, if it expects to read from a directory.

ParameterFile
Type:

String

Default value:

Description:

Path to a set of parameters for the backend, if it expects to read from a file.

UnpairedElectrons
Type:

Integer

Default value:

0

Value Range:

value >= 0

GUI name:

Spin polarization

Description:

The number of unpaired electrons in the system for a spin unrestricted calculation. The spin multiplicity is taken as this value plus one.

Unrestricted
Type:

Bool

Default value:

No

Description:

Enables spin unrestricted calculations, passing spin information to models that accept spin input.