MLIPs Ontology

Title: MLIPs Ontology: An Ontology for Machine Learning Interatomic Potentials

An OWL ontology capturing the concepts needed to describe machine learning interatomic potentials: algorithm families, hyperparameters, training datasets with DFT provenance, and published benchmarks.

Version: 0.1.0

Namespace: https://w3id.org/mlips#

Prefix: mlips:

Persistent IRI: https://w3id.org/mlips

Licence: CC BY 4.0

Editors:

Contributors:

Algorithm Module

Classes

Hyperparameter

A hyperparameter of an MLIP method, with its name, data type, range, and default value.

Subclass of: mlschema:HyperParameter


  Hyperparameter
  A hyperparameter of an MLIP method, with its name,
data type, range, and default value.
  
  
    
      
        
          
        
      
      
    
  
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Physical Hyperparameter

A hyperparameter that has a direct physical meaning (e.g., the cutoff radius bounds the physical interaction range, the minimum distance bounds short-range repulsion). Not disjoint with ArchitecturalHyperparameter: many MLIP hyperparameters are simultaneously architectural and physical.

Subclass of: mlips:Hyperparameter


  Physical Hyperparameter
  A hyperparameter that has a direct physical
meaning. Not disjoint with ArchitecturalHyperparameter.
  
]]>

Architectural Hyperparameter

A hyperparameter that specifies the architecture of the model (number of layers, number of basis functions, maximum moment level, etc.). Not disjoint with PhysicalHyperparameter.

Subclass of: mlips:Hyperparameter


  Architectural Hyperparameter
  A hyperparameter that specifies the model
architecture. Not disjoint with PhysicalHyperparameter.
  
]]>

Training Hyperparameter

A hyperparameter of the training procedure (optimizer type, learning rate, batch size, loss-term weights, regularization strength). These are parameters of how the model is fitted, not of the model itself.

Subclass of: mlips:Hyperparameter


  Training Hyperparameter
  A hyperparameter of the training procedure.
  
]]>

Hyperparameter Setting

A concrete value assigned to a hyperparameter in a specific training run or configuration.


  Hyperparameter Setting
  A concrete value assigned to a hyperparameter in a
specific training run or configuration.
]]>

Implementation

A software implementation of an MLIP method in a specific library and version.

Subclass of: mlschema:Implementation


  Implementation
  A software implementation of an MLIP method in a
specific library and version.
  
  
    
      
      
    
  
  
    
      
        
          
        
      
      
    
  
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Library

A software library or tool used in MLIP research (e.g., ASE, LAMMPS, VASP, GPAW).


  Library
  A software library or tool used in MLIP research
(e.g., ASE, LAMMPS, VASP, GPAW).
]]>

MLIP Method

A machine learning interatomic potential method family (e.g., MACE, ACE, HDNNP, NequIP, M3GNet, MTP). An MLIP method specifies a functional form mapping an atomic configuration to an energy, a loss function defined over that form, and a training algorithm used to fit its parameters. MLIPMethod is disjoint from mls:Algorithm: an MLIP method is a named specification of all three components, whereas mls:Algorithm refers to a training/learning procedure (e.g., Adam, L-BFGS).

Disjoint with: mlschema:Algorithm


  MLIP Method
  A machine learning interatomic potential method family
(e.g., MACE, ACE, HDNNP, NequIP, M3GNet, MTP). Specifies a functional form,
a loss function, and a training algorithm. Disjoint from mls:Algorithm.
  
  
    
      
      
    
  
  
    
      
      
    
  
  
    
      
      
    
  
  
    
      
      
    
  
  
    
      
      
    
  
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Functional Form

A parametrised mapping from an atomic configuration to an energy (and derived quantities such as forces and stresses), specified independently of the values of its parameters. Examples: the MTP moment-tensor polynomial $E(\text{cfg}; \boldsymbol{\xi})$, the MACE message-passing ansatz, the HDNNP sum of atomic neural networks. The functional form is what is being fitted; the trained model records the fitted parameter values.


  Functional Form
  A parametrised mapping from an atomic configuration to an energy, specified independently of parameter values.
]]>

Loss Function

A scalar objective whose minimisation fits the parameters of the functional form. For MLIPs it is typically a weighted sum of mean-squared errors on energies, forces, and stresses, optionally with regularisation terms.


  Loss Function
  A scalar objective whose minimisation fits the parameters of the functional form.
]]>

Simulation Type

A type of atomistic simulation: molecular dynamics, Monte Carlo, geometry optimization, phonon calculations, thermodynamic integration, etc.


  Simulation Type
  A type of atomistic simulation: molecular dynamics,
Monte Carlo, geometry optimization, phonon calculations,
thermodynamic integration, etc.
]]>

Trained Model

The concrete artifact produced by fitting an MLIP method on a specific dataset with specific hyperparameter settings---the learned parameters (weights) that can be used for prediction.

Subclass of: mlschema:Model


  Trained Model
  The concrete artifact produced by fitting an MLIP method
on a specific dataset with specific hyperparameter settings---the learned
parameters (weights) that can be used for prediction.
  
  
    
      
        
          
        
      
      
    
  
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MLIP Run

A concrete fitting activity for an MLIP method: it applies an MLIP method to a training dataset and produces a trained model. MLIPRun is a subclass of prov:Activity but not of mls:Run, because the mls:Run.executes property ranges over mls:Algorithm and mlips:MLIPMethod is disjoint from mls:Algorithm. An optional hasTrainingRun property links an MLIPRun to an underlying mls:Run when the training algorithm is itself modelled in ML-Schema.

Subclass of: prov:Activity


  MLIP Run
  A concrete fitting activity for an MLIP method: it applies an MLIP method to a training dataset and produces a trained model.
  
  
    
      
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Atomic Environment Descriptor

A mathematical representation of the local atomic environment (neighbor positions and types) used by an MLIP algorithm. Different algorithms use different descriptors: moment tensors (MTP), SOAP (GAP), symmetry functions (HDNNP), equivariant message passing (MACE, NequIP), or atomic cluster expansion (ACE).


  Atomic Environment Descriptor
  A mathematical representation of the local atomic environment used by an MLIP method.
]]>

Object Properties

evaluates model

Links a benchmark result to the trained model being evaluated.

Domain
BenchmarkResult
Range
TrainedModel

  evaluates model
  Links a benchmark result to the trained model being evaluated.
  
  
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applies method

Links an MLIP run to the MLIP method it fits.

Domain
MLIPRun
Range
MLIPMethod

  applies method
  Links an MLIP run to the MLIP method it fits.
  
  
]]>

has functional form

Links an MLIP method to its parametrised functional form.

Domain
MLIPMethod
Range
FunctionalForm

  has functional form
  Links an MLIP method to its parametrised functional form.
  
  
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has loss function

Links an MLIP method to the loss function whose minimisation fits its parameters.

Domain
MLIPMethod
Range
LossFunction

  has loss function
  Links an MLIP method to the loss function whose minimisation fits its parameters.
  
  
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has training algorithm

Links an MLIP method to the ML-Schema algorithm used to fit its functional form by minimising its loss function. This is the alignment point with ML-Schema: while MLIPMethod is disjoint from mls:Algorithm, every MLIP method names the training algorithm (e.g., L-BFGS, Adam, stochastic gradient descent) as an mls:Algorithm instance.

Domain
MLIPMethod
Range
mlschema:Algorithm

  has training algorithm
  Links an MLIP method to the ML-Schema algorithm used to fit its functional form.
  
  
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has training run

Optional link from an MLIP run to the underlying ML-Schema run that records the execution of the training algorithm. Use when the training algorithm is itself modelled in ML-Schema; omit otherwise.

Domain
MLIPRun
Range
mlschema:Run

  has training run
  Optional link from an MLIP run to an ML-Schema run recording the training algorithm execution.
  
  
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for hyperparameter

Links a setting to the hyperparameter it configures.

Domain
HyperparameterSetting
Range
Hyperparameter

  for hyperparameter
  Links a setting to the hyperparameter it configures.
  
  
]]>

has hyperparameter

Links an MLIP method to a hyperparameter it accepts.

Domain
MLIPMethod
Range
Hyperparameter

  has hyperparameter
  Links an MLIP method to a hyperparameter it accepts.
  
  
]]>

has implementation

Links an MLIP method to a software implementation.

Domain
MLIPMethod
Range
Implementation

  has implementation
  Links an MLIP method to a software implementation.
  
  
]]>

implemented in

Links an implementation to the library that provides it.

Domain
Implementation
Range
Library

  implemented in
  Links an implementation to the library that provides it.
  
  
]]>

produces

Links an MLIP run to the trained model it produces.

Domain
MLIPRun
Range
TrainedModel

  produces
  Links an MLIP run to the trained model it produces.
  
  
]]>

runs on

Links an MLIP run to the training dataset it uses.

Domain
MLIPRun
Range
TrainingDataset

  runs on
  Links an MLIP run to the training dataset it uses.
  
  
]]>

supports simulation

Links an MLIP method to the simulation types it supports.

Domain
MLIPMethod
Range
SimulationType

  supports simulation
  Links an MLIP method to the simulation types it supports.
  
  
]]>

trained on

Shortcut: links a trained model directly to the training dataset it was fitted on.

Domain
TrainedModel
Range
TrainingDataset

  trained on
  Shortcut: links a trained model directly to the training dataset it was fitted on.
  
  
  
    
      
    
    
  
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trained with

Shortcut: links a trained model directly to the MLIP method it applies.

Domain
TrainedModel
Range
MLIPMethod

  trained with
  Shortcut: links a trained model directly to the MLIP method it applies.
  
  
  
    
      
    
    
  
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trained using

Shortcut: links a trained model directly to a hyperparameter setting used during the MLIP run that produced it.

Domain
TrainedModel
Range
HyperparameterSetting

  trained using
  Shortcut: links a trained model directly to a hyperparameter setting used during the MLIP run that produced it.
  
  
  
    
      
    
    
  
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has descriptor

Links an MLIP method to the atomic environment descriptor it uses to represent local neighborhoods.

Domain
MLIPMethod
Range
AtomicEnvironmentDescriptor

  has descriptor
  Links an MLIP method to the atomic environment descriptor it uses.
  
  
]]>

Individuals

Moment Tensor Descriptor

Type: AtomicEnvironmentDescriptor


  
  Moment Tensor Descriptor
  Invariant moment tensors of the neighborhood; used by MTP.
]]>

SOAP Descriptor

Type: AtomicEnvironmentDescriptor


  
  SOAP Descriptor
  Smooth Overlap of Atomic Positions; used by GAP.
]]>

Symmetry Function Descriptor

Type: AtomicEnvironmentDescriptor


  
  Symmetry Function Descriptor
  Behler-Parrinello symmetry functions; used by HDNNP.
]]>

Equivariant Message Passing Descriptor

Type: AtomicEnvironmentDescriptor


  
  Equivariant Message Passing Descriptor
  Equivariant message-passing representation; used by MACE and NequIP.
]]>

Atomic Cluster Expansion Descriptor

Type: AtomicEnvironmentDescriptor


  
  Atomic Cluster Expansion Descriptor
  Atomic cluster expansion; used by ACE.
]]>

Datatype Properties

cutoff radius

Cutoff radius for atomic interactions, in angstroms.

Domain
HyperparameterSetting
Range
xsd:double

  cutoff radius
  Cutoff radius for atomic interactions, in angstroms.
  
  
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default value

Domain
Hyperparameter
Range
rdfs:Literal

  default value
  
  
]]>

hyperparameter datatype

The expected datatype of this hyperparameter (e.g., float, int, string).

Domain
Hyperparameter
Range
xsd:string

  hyperparameter datatype
  The expected datatype of this hyperparameter (e.g., float, int, string).
  
  
]]>

hyperparameter name

Domain
Hyperparameter
Range
xsd:string

  hyperparameter name
  
  
]]>

learning rate

Learning rate used during model training.

Domain
HyperparameterSetting
Range
xsd:double

  learning rate
  Learning rate used during model training.
  
  
]]>

maximum value

Domain
Hyperparameter
Range
rdfs:Literal

  maximum value
  
  
]]>

minimum value

Domain
Hyperparameter
Range
rdfs:Literal

  minimum value
  
  
]]>

number of angular basis functions

Number of angular basis functions in the descriptor.

Domain
HyperparameterSetting
Range
xsd:integer

  number of angular basis functions
  Number of angular basis functions in the descriptor.
  
  
]]>

number of layers

Number of layers in the neural network architecture.

Domain
HyperparameterSetting
Range
xsd:integer

  number of layers
  Number of layers in the neural network architecture.
  
  
]]>

number of radial basis functions

Number of radial basis functions in the descriptor.

Domain
HyperparameterSetting
Range
xsd:integer

  number of radial basis functions
  Number of radial basis functions in the descriptor.
  
  
]]>

setting value

Domain
HyperparameterSetting
Range
rdfs:Literal

  setting value
  
  
]]>

version

Domain
Implementation
Range
xsd:string

  version
  
  
]]>

training complexity

Asymptotic computational complexity of fitting the MLIP method, as a prior-knowledge annotation (e.g., "O(N)", "O(N log N)"). This is a property of the method itself, independent of any specific MLIP run.

Domain
MLIPMethod
Range
xsd:string

  training complexity
  Asymptotic computational complexity of training.
  
  
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inference complexity

Asymptotic computational complexity of running the trained potential on a system, as a prior-knowledge annotation (e.g., "O(N)" for local potentials).

Domain
MLIPMethod
Range
xsd:string

  inference complexity
  Asymptotic computational complexity of inference.
  
  
]]>

supports GPU

Whether the algorithm (in its canonical implementation) supports GPU acceleration.

Domain
MLIPMethod
Range
xsd:boolean

  supports GPU
  
  
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supports parallelization

Whether the algorithm supports multi-node or multi-core parallel training and inference.

Domain
MLIPMethod
Range
xsd:boolean

  supports parallelization
  
  
]]>

training duration

Measured wall-clock time of a training run, in hours.

Domain
MLIPRun
Range
xsd:double

  training duration
  Measured wall-clock training time (hours).
  
  
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training hardware

Hardware used in the MLIP run (e.g., "NVIDIA A100", "Intel Xeon 8-core CPU").

Domain
MLIPRun
Range
xsd:string

  training hardware
  
  
]]>

peak memory

Peak memory usage during training, in gigabytes.

Domain
MLIPRun
Range
xsd:double

  peak memory
  Peak memory during training (GB).
  
  
]]>

GPU hours

Total GPU-hours consumed by the training run.

Domain
MLIPRun
Range
xsd:double

  GPU hours
  
  
]]>

Training Data Module

Classes

Atomic Configuration

A single atomic configuration (positions, cell, properties) in a training dataset.

Subclass of: cmso:AtomicStructure


  Atomic Configuration
  A single atomic configuration (positions, cell,
properties) in a training dataset.
  
]]>

Covered Property

A physical property covered by the training dataset (energy, forces, stresses, virials).


  Covered Property
  A physical property covered by the training dataset
(energy, forces, stresses, virials).
]]>

DFT Calculation

A density functional theory calculation that produced reference data for training.

Subclass of: mlips:ReferenceCalculation, mdo:Calculation


  DFT Calculation
  A density functional theory calculation that produced
reference data for training.
  
  
  
    
      
      
    
  
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DFT Settings

Settings of a DFT calculation: exchange-correlation functional, k-point mesh, energy cutoff, pseudopotential type.

Subclass of: mlips:ReferenceSettings


  DFT Settings
  Settings of a DFT calculation: exchange-correlation
functional, k-point mesh, energy cutoff, pseudopotential type.
  
]]>

Dataset Provenance

The provenance type of a training dataset.


  Dataset Provenance
  The provenance type of a training dataset.
]]>

DFT Basis Set

The basis set used in a DFT calculation, when the code is all-electron or otherwise uses a localised basis (e.g., FHI-aims NAO families, LAPW, Gaussian-type orbitals such as cc-pVDZ or 6-31G). Range of $\dlRole{dftBasisSet}$ on $\DFTSettingsC$. Plane- wave codes specify the basis through $\dlRole{energyCutoff}$ instead and leave this slot empty. Concrete basis sets are modelled as named individuals; an open extension point. Where the corpus uses a basis set not in the controlled vocabulary, a paper-local instance is minted and tagged with $\dlRole{candidateForVocabulary}$ for later review.


  DFT Basis Set
  The basis set used in a DFT calculation,
when the code is all-electron or otherwise uses a localised basis (e.g.,
FHI-aims NAO families, LAPW, Gaussian-type orbitals such as cc-pVDZ
or 6-31G). Range of mlips:dftBasisSet on DFTSettings. Plane-wave
codes specify the basis through mlips:energyCutoff instead and leave
this slot empty. Concrete basis sets are modelled as named individuals;
an open extension point.
]]>

Material System

A material system studied in a dataset: element, alloy, compound, or complex microstructure.

Subclass of: cmso:CrystallineMaterial


  Material System
  A material system studied in a dataset: element, alloy,
compound, or complex microstructure.
  
]]>

Pseudopotential Type

A family of pseudopotentials used in a plane-wave DFT calculation (e.g., PAW, ultrasoft, norm-conserving). Range of $\dlRole{pseudopotentialType}$ on $\DFTSettingsC$. All-electron codes leave this slot empty. Concrete pseudopotential families are modelled as named individuals; an open extension point.


  Pseudopotential Type
  A family of pseudopotentials used in a
plane-wave DFT calculation (e.g., PAW, ultrasoft, norm-conserving).
Range of mlips:pseudopotentialType on DFTSettings. All-electron codes
leave this slot empty. Concrete pseudopotential families are modelled
as named individuals; an open extension point.
]]>

Reference Calculation

A first-principles calculation that produced reference energies, forces, or stresses for MLIP training. Generalisation of DFTCalculation that also covers wave-function methods (e.g., CCSD(T), MP2, CASPT2) and other ab initio approaches.

Subclass of: mdo:Calculation


  Reference Calculation
  A first-principles calculation that produced
reference energies, forces, or stresses for MLIP training. Generalisation of
DFTCalculation that also covers wave-function methods (e.g., CCSD(T), MP2,
CASPT2) and other ab initio approaches.
  
  
    
      
      
    
  
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Reference Settings

Settings of a reference calculation, abstracted across method families. Concrete subclasses (DFTSettings, WaveFunctionSettings) carry the method-specific parameters; the supertype carries cross-family slots such as the software code used.


  Reference Settings
  Settings of a reference calculation, abstracted
across method families. Concrete subclasses (DFTSettings, WaveFunctionSettings)
carry the method-specific parameters; the supertype carries cross-family slots
such as the software code used.
]]>

Sampling Strategy

A strategy used to sample the atomic configurations in a training dataset (e.g., chemical sampling across compositions, vibrational sampling across thermal snapshots, or a combination). Concrete sampling strategies are modeled as instances and will be developed in future work; this class is left open as an extension point.


  Sampling Strategy
  A strategy used to sample the atomic
configurations in a training dataset (e.g., chemical sampling across
compositions, vibrational sampling across thermal snapshots, or a
combination). Concrete sampling strategies are modeled as instances and
will be developed in future work; this class is left open as an
extension point.
]]>

Training Dataset

A dataset of atomic configurations used for MLIP training, with provenance, size, property coverage, and DFT settings.

Subclass of: mlschema:Dataset, prov:Entity


  Training Dataset
  A dataset of atomic configurations used for MLIP
training, with provenance, size, property coverage, and DFT settings.
  
  
  
    
      
      
    
  
  
    
      
      
    
  
  
    
      
      
    
  
  
    
      
      
    
  
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Wave Function Calculation

A wave-function-based reference calculation (e.g., Hartree--Fock, MP2, CCSD, CCSD(T), CASPT2). An alternative to DFTCalculation as a source of reference data, typically more accurate but more expensive.

Subclass of: mlips:ReferenceCalculation


  Wave Function Calculation
  A wave-function-based reference calculation
(e.g., Hartree-Fock, MP2, CCSD, CCSD(T), CASPT2). An alternative to
DFTCalculation as a source of reference data, typically more accurate but
more expensive.
  
  
    
      
      
    
  
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Wave Function Settings

Settings of a wave-function-based reference calculation: the method (e.g., CCSD(T), MP2), the basis set (e.g., cc-pVTZ, aug-cc-pVDZ), and frozen-core treatment.

Subclass of: mlips:ReferenceSettings


  Wave Function Settings
  Settings of a wave-function-based reference
calculation: the method (e.g., CCSD(T), MP2), the basis set (e.g.,
cc-pVTZ, aug-cc-pVDZ), and frozen-core treatment.
  
]]>

Wave Function Method

A wave-function correlation method used to produce reference data (e.g., HF, MP2, CCSD, CCSD(T), DLPNO-CCSD(T), CASPT2, NEVPT2). Range of $\dlRole{wfMethod}$ on $\WaveFunctionSettingsC$. Concrete methods are modelled as named individuals; an open extension point.


  Wave Function Method
  A wave-function correlation method used to
produce reference data (e.g., HF, MP2, CCSD, CCSD(T), DLPNO-CCSD(T),
CASPT2, NEVPT2). Range of mlips:wfMethod on WaveFunctionSettings.
Concrete methods are modelled as named individuals; an open
extension point.
]]>

Exchange-Correlation Functional

A density-functional approximation to the exchange-correlation energy used in a DFT calculation (e.g., LDA, PBE, PBE0, HSE06, SCAN, BLYP, omegaB97X). Range of $\dlRole{xcFunctional}$ on $\DFTSettingsC$. Concrete functionals are modelled as named individuals; an open extension point.


  Exchange-Correlation Functional
  A density-functional approximation to the
exchange-correlation energy used in a DFT calculation (e.g., LDA, PBE,
PBE0, HSE06, SCAN, BLYP, omegaB97X). Range of mlips:xcFunctional on
DFTSettings. Concrete functionals are modelled as named individuals;
an open extension point.
]]>

Object Properties

candidate for vocabulary

Annotates a paper-local instance with the controlled-vocabulary class to which it should be considered for promotion. Used when an encoded paper introduces an entity (e.g., a new exchange-correlation functional, a new wave-function method, a new pseudopotential family) that is not yet a named individual in mlips-vocab.ttl. The deduplication audit collects these candidates; a curator promotes, merges, or leaves them paper-local. Range is the target vocabulary class (e.g., $\XCFunctionalC$, $\WfMethodC$, $\DftBasisSetC$, $\PseudopotentialTypeC$).

Domain
owl:Thing
Range
owl:Class

  candidate for vocabulary
  Annotates a paper-local instance with the
controlled-vocabulary class to which it should be considered for
promotion. Used when an encoded paper introduces an entity that is not
yet a named individual in mlips-vocab.ttl. The deduplication audit
collects these candidates; a curator promotes, merges, or leaves them
paper-local.
]]>

covers material

Domain
TrainingDataset
Range
MaterialSystem

  covers material
  
  
]]>

covers property

Domain
TrainingDataset
Range
CoveredProperty

  covers property
  
  
]]>

dataset provenance

Domain
TrainingDataset
Range
DatasetProvenance

  dataset provenance
  
  
]]>

DFT basis set

The basis set used by an all-electron or localised-basis DFT calculation (FHI-aims NAO, LAPW, Gaussian-type orbitals such as cc-pVDZ or 6-31G). Plane-wave codes specify the basis through $\dlRole{energyCutoff}$ and leave this slot empty.

Domain
DFTSettings
Range
DftBasisSet

  DFT basis set
  The basis set used by an all-electron or
localised-basis DFT calculation (FHI-aims NAO, LAPW, Gaussian-type
orbitals such as cc-pVDZ or 6-31G). Plane-wave codes specify the basis
through mlips:energyCutoff and leave this slot empty.
  
  
]]>

has configuration

Domain
TrainingDataset
Range
AtomicConfiguration

  has configuration
  
  
]]>

has DFT calculation

Subproperty of: mlips:hasReferenceCalculation

Domain
TrainingDataset
Range
DFTCalculation

  has DFT calculation
  
  
  
]]>

has DFT settings

Subproperty of: mlips:hasReferenceSettings

Domain
DFTCalculation
Range
DFTSettings

  has DFT settings
  
  
  
]]>

has reference calculation

Links a training dataset to the first-principles calculation that produced its reference data. Generalises hasDFTCalculation to wave-function and other ab initio methods.

Domain
TrainingDataset
Range
ReferenceCalculation

  has reference calculation
  Links a training dataset to the
first-principles calculation that produced its reference data.
Generalises hasDFTCalculation to wave-function and other ab initio
methods.
  
  
]]>

has reference settings

Links a reference calculation to its method-specific settings. Generalises hasDFTSettings to wave-function and other ab initio methods.

Domain
ReferenceCalculation
Range
ReferenceSettings

  has reference settings
  Links a reference calculation to its
method-specific settings. Generalises hasDFTSettings to wave-function
and other ab initio methods.
  
  
]]>

has wave function settings

Subproperty of: mlips:hasReferenceSettings

Domain
WaveFunctionCalculation
Range
WaveFunctionSettings

  has wave function settings
  
  
  
]]>

pseudopotential type

The family of pseudopotentials used in a plane-wave DFT calculation (PAW, ultrasoft, norm-conserving). All- electron codes leave this slot empty and use $\dlRole{dftBasisSet}$ instead.

Domain
DFTSettings
Range
PseudopotentialType

  pseudopotential type
  The family of pseudopotentials used in a
plane-wave DFT calculation (PAW, ultrasoft, norm-conserving). All-
electron codes leave this slot empty and use mlips:dftBasisSet
instead.
  
  
]]>

sampling strategy

Records the sampling strategy or strategies used to construct a training dataset. Optional and multi-valued: a dataset may combine several sampling strategies (e.g., chemical and vibrational).

Domain
TrainingDataset
Range
SamplingStrategy

  sampling strategy
  Records the sampling strategy or strategies
used to construct a training dataset. Optional and multi-valued: a
dataset may combine several sampling strategies (e.g., chemical and
vibrational).
  
  
]]>

used DFT code

The DFT software used (e.g., VASP, GPAW).

Subproperty of: mlips:usedReferenceCode

Domain
DFTSettings
Range
Library

  used DFT code
  The DFT software used (e.g., VASP, GPAW).
  
  
  
]]>

used reference code

The software code used to perform the reference calculation (e.g., VASP, GPAW for DFT; Molpro, PySCF, ORCA for wave-function methods). Generalises usedDFTCode.

Domain
ReferenceSettings
Range
Library

  used reference code
  The software code used to perform the
reference calculation (e.g., VASP, GPAW for DFT; Molpro, PySCF, ORCA
for wave-function methods). Generalises usedDFTCode.
  
  
]]>

wave-function method

The wave-function correlation method used to produce reference data (e.g., HF, MP2, CCSD, CCSD(T), DLPNO-CCSD(T), CASPT2, NEVPT2). Range is $\WfMethodC$; concrete methods are named individuals in mlips-vocab.ttl.

Domain
WaveFunctionSettings
Range
WfMethod

  wave-function method
  The wave-function correlation method used
to produce reference data (e.g., HF, MP2, CCSD, CCSD(T), DLPNO-CCSD(T),
CASPT2, NEVPT2). Range is WfMethod; concrete methods are named
individuals in mlips-vocab.ttl.
  
  
]]>

exchange-correlation functional

The exchange-correlation functional used in a DFT calculation (e.g., LDA, PBE, PBE0, HSE06, SCAN, omegaB97X). Range is $\XCFunctionalC$; concrete functionals are named individuals in mlips-vocab.ttl.

Domain
DFTSettings
Range
XCFunctional

  exchange-correlation functional
  The exchange-correlation functional used in
a DFT calculation (e.g., LDA, PBE, PBE0, HSE06, SCAN, omegaB97X). Range
is XCFunctional; concrete functionals are named individuals in
mlips-vocab.ttl.
  
  
]]>

Datatype Properties

basis set

The Gaussian basis set used in a wave-function calculation, e.g., cc-pVTZ, aug-cc-pVDZ, def2-TZVP.

Domain
WaveFunctionSettings
Range
xsd:string

  basis set
  The Gaussian basis set used in a
wave-function calculation, e.g., cc-pVTZ, aug-cc-pVDZ, def2-TZVP.
  
  
]]>

chemical formula

Domain
MaterialSystem
Range
xsd:string

  chemical formula
  
  
]]>

energy cutoff

Plane-wave energy cutoff in eV.

Domain
DFTSettings
Range
xsd:double

  energy cutoff
  Plane-wave energy cutoff in eV.
  
  
]]>

frozen core

Whether core electrons are kept frozen during the post-Hartree--Fock correlation treatment in a wave-function calculation. True for the standard frozen-core approximation; false for all-electron correlation.

Domain
WaveFunctionSettings
Range
xsd:boolean

  frozen core
  Whether core electrons are kept frozen
during the post-Hartree-Fock correlation treatment in a wave-function
calculation. True for the standard frozen-core approximation; false
for all-electron correlation.
  
  
]]>

k-point mesh

K-point mesh specification (e.g., '4x4x4').

Domain
DFTSettings
Range
xsd:string

  k-point mesh
  K-point mesh specification (e.g., '4x4x4').
  
  
]]>

material class

E.g., element, binary alloy, ternary compound, HEA.

Domain
MaterialSystem
Range
xsd:string

  material class
  E.g., element, binary alloy, ternary compound, HEA.
  
  
]]>

microstructural feature

E.g., point defect, dislocation, surface, grain boundary.

Domain
MaterialSystem
Range
xsd:string

  microstructural feature
  E.g., point defect, dislocation, surface, grain boundary.
  
  
]]>

number of configurations

Domain
TrainingDataset
Range
xsd:integer

  number of configurations
  
  
]]>

Individuals

Augmented

Dataset augmented from existing sources.

Type: DatasetProvenance


  
  Augmented
  Dataset augmented from existing sources.
]]>

Energy

Type: CoveredProperty


  
  Energy
]]>

Forces

Type: CoveredProperty


  
  Forces
]]>

In-house

Dataset generated by in-house calculations.

Type: DatasetProvenance


  
  In-house
  Dataset generated by in-house calculations.
]]>

Published

Dataset from a published source.

Type: DatasetProvenance


  
  Published
  Dataset from a published source.
]]>

Stresses

Type: CoveredProperty


  
  Stresses
]]>

Virials

Type: CoveredProperty


  
  Virials
]]>

Benchmark Module

Classes

Accuracy Metric

An accuracy measure reported in a benchmark (e.g., RMSE of energy, MAE of forces).


  Accuracy Metric
  An accuracy measure reported in a benchmark
(e.g., RMSE of energy, MAE of forces).
  
    
      
      1
      
    
  
  
    
      
      1
      
    
  
  
    
      
        
          
        
      
      
    
  
]]>

Benchmark Result

A single evaluation result: an MLIP method applied to a material system with specific hyperparameters, reporting accuracy metrics.


  Benchmark Result
  A single evaluation result: an MLIP method applied to a
material system with specific hyperparameters, reporting accuracy metrics.
  
    
      
      1
      
    
  
  
    
      
      
    
  
  
    
      
      
    
  
  
    
      
        
          
        
      
      
    
  
]]>

Benchmark Study

A published study reporting MLIP evaluation results.

Subclass of: prov:Activity


  Benchmark Study
  A published study reporting MLIP evaluation results.
  
  
    
      
      
    
  
]]>

Metric Property

The physical property being measured (energy, force, stress).


  Metric Property
  The physical property being measured (energy, force, stress).
]]>

Metric Type

Type of accuracy metric (RMSE, MAE, R², etc.).


  Metric Type
  Type of accuracy metric (RMSE, MAE, R², etc.).
]]>

Object Properties

has accuracy metric

Domain
BenchmarkResult
Range
AccuracyMetric

  has accuracy metric
  
  
]]>

has hyperparameter setting

Links an MLIP run to a concrete value chosen for one of the hyperparameters of the MLIP method it applies. The collection of these settings, together with the method and the training dataset, fully characterises what was fitted in the run.

Domain
MLIPRun
Range
HyperparameterSetting

  has hyperparameter setting
  Links an MLIP run to a concrete hyperparameter setting used in that run.
  
  
]]>

has result

Domain
BenchmarkStudy
Range
BenchmarkResult

  has result
  
  
]]>

metric property

Domain
AccuracyMetric
Range
MetricProperty

  metric property
  
  
]]>

metric type

Domain
AccuracyMetric
Range
MetricType

  metric type
  
  
]]>

reported in

Domain
BenchmarkResult
Range
ScholarlyArticle

  reported in
  
  
]]>

target material

Domain
BenchmarkResult
Range
MaterialSystem

  target material
  
  
]]>

uses algorithm

Domain
BenchmarkResult
Range
MLIPMethod

  uses algorithm
  
  
]]>

uses training data

Domain
BenchmarkResult
Range
TrainingDataset

  uses training data
  
  
]]>

Datatype Properties

metric value

Domain
AccuracyMetric
Range
xsd:double

  metric value
  
  
]]>

inference time per atom

Measured wall-clock inference time per atom, in microseconds. Captured on a specific benchmark result.

Domain
BenchmarkResult
Range
xsd:double

  inference time per atom
  Inference time per atom (microseconds).
  
  
]]>

inference hardware

Hardware used for the inference benchmark (e.g., "NVIDIA A100", "Apple M2").

Domain
BenchmarkResult
Range
xsd:string

  inference hardware
  
  
]]>

Individuals

Energy (metric property)

Type: MetricProperty


  
  Energy (metric property)
]]>

Force

Type: MetricProperty


  
  Force
]]>

MAE

Mean Absolute Error.

Type: MetricType


  
  MAE
  Mean Absolute Error.
]]>

Coefficient of determination.

Type: MetricType


  
  
  Coefficient of determination.
]]>

RMSE

Root Mean Square Error.

Type: MetricType


  
  RMSE
  Root Mean Square Error.
]]>

Stress

Type: MetricProperty


  
  Stress
]]>

Cross-Module Properties

Object Properties

has unit

Links a numeric value to its QUDT unit.

Range
Unit

  has unit
  Links a numeric value to its QUDT unit.
  
]]>

same as Wikidata

Links an entity to its corresponding Wikidata item.


  same as Wikidata
  Links an entity to its corresponding Wikidata item.
  
]]>