ml-foundation-potentials
Agent BuildingGuide for selecting the most appropriate foundation MLIP model based on simulation requirements.
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Foundation Potentials Selection
Goal
Select the appropriate machine learning interatomic potential (MLIP) for a given atomistic simulation task, balancing accuracy, computational cost, and material composition.
Model Selection Guide
[!NOTE] This list is not exhaustive. For a full list of available pre-trained checkpoints, refer to the
load_modelfunction documentation for each respective MCP server.
MatGL Models
Environment: matgl-agent
- CHGNet-MatPES-r2SCAN-2025.2.10-2.7M-PES:
- Use for r2SCAN-level inorganic materials simulation.
- Recommended when charge information and magnetic moments are involved (e.g., calculating transition metal valence states).
- CHGNet-MPtrj-2023.12.1-2.7M-PES:
- Use for compatibility with standard Materials Project (GGA/GGA+U) data.
- Recommended when working with legacy MP data.
- TensorNet-MatPES-r2SCAN-v2025.1-PES:
- Use for r2SCAN-level inorganic materials simulation.
- Smaller and faster than CHGNet, suitable for dynamic simulations (MD, NEB, phonons).
FAIRCHEM Models
Environment: fairchem-agent
- uma-s-1p1:
- Use for organic and inorganic simulations.
- Note: UMA models are typically slower and more expensive. Avoid for dynamic simulations with systems >500 atoms.
- uma-m-1p1:
- Use for organic and inorganic simulations with <100 atoms.
- esen-md-direct-all-omol:
- Use for organic ionic relaxation (ground state calculations).
MACE Models
Environment: mace-agent
- MACE-MH-1:
- Latest multi-head foundation model. Use as default for most tasks.
omat_pbehead (default): General materials, balanced performance.matpes_r2scanhead: High-accuracy materials simulation.omolhead: Molecular systems, organic chemistry, organometallics.spice_wB97Mhead: Molecular systems and organic chemistry.oc20_usemppbehead: Surface catalysis, adsorbates.
- MACE-MATPES-r2SCAN-0:
- Specialized for r2SCAN-level inorganic systems.
- MACE-OMAT-0-small:
- Small, efficient model for materials.
Selection Criteria
Prioritize criteria in the following order:
0. Check the Local Model Registry (Always First)
Before selecting any foundation model, call search_model_registry to check whether a fine-tuned checkpoint already exists for the target chemical system:
mcp_base_search_model_registry(
chemical_system="Li-Fe-P-O", # elements of interest
max_energy_mae=5.0, # optional accuracy filter (meV/atom)
)
- If a match is found and
checkpoint_exists = True, use that model directly — no foundation model selection or fine-tuning is needed. - If a match is found but
checkpoint_exists = False(file missing), fall through to the criteria below and plan a new fine-tuning run. - If no match is found, continue with the criteria below to select the best foundation model.
[!TIP] After completing any fine-tuning, always register the new model with
register_modelso it can be reused in future tasks.
1. User Explicit Request
If the user explicitly mentions a model name or framework (e.g., "MACE model", "fine-tuned MACE", "CHGNet", "UMA"), use that model/framework.
- Detect frameworks from keywords like: "MACE", "CHGNet", "TensorNet", "UMA", "ESEN", "FAIRCHEM", "MatGL".
2. Calculation Expense
If the simulation involves dynamic or expensive calculations (Molecular Dynamics, NEB, Phonons, Diffusion, Melting Temperature):
- Prioritize smaller/cheaper models: structure
TensorNet-MatPES-r2SCAN-v2025.1-PESMACE-MATPES-r2SCAN-0(or MACE small variants)
- Avoid UMA models for dynamic simulations due to higher cost, unless the system is very small.
3. System Composition
Consider the chemical elements present in the system:
- Organic (C, H, N, O, P, S):
- Use UMA models or MACE-MH-1 with
omolhead.
- Use UMA models or MACE-MH-1 with
- Inorganic:
- Use MatGL, MACE models, or UMA with
omathead.
- Use MatGL, MACE models, or UMA with
- For Phase Diagrams & Thermodynamic Stability:
- It is highly recommended to use MatPES-r2SCAN trained checkpoints (e.g.,
CHGNet-MatPES-r2SCAN,MACE-MATPES-r2SCAN). These offer superior energy accuracy for phase stability and bypass messy energy compatibility corrections in GGA (see mat-mp2020-compatibility).
- It is highly recommended to use MatPES-r2SCAN trained checkpoints (e.g.,
4. Default
For general materials where no specific constraints apply:
- Use MACE-MH-1 with
omat_pbehead.
Performance Benchmark
For detailed inference speed and memory usage of various MLIPs, refer to the dedicated ml-mlip-speed skill. This skill provides automatic benchmarks to help you choose the most efficient model for your simulation scale.
Author: Bowen Deng Contact: GitHub @learningmatter-mit