Structure Relaxation

What This Tool Does

Batch-relax uploaded CIF structures with MatterSim or a compiled NequIP model, then export relaxed CIFs and human-readable summary tables.

Typical Inputs

• One or more CIF files, or a ZIP/TAR.GZ archive containing CIF files.
• Relaxation model: MatterSim or NequIP OAM XL.
• Device: auto, CPU, or CUDA. Auto uses CUDA when the worker runtime exposes it and falls back to CPU.
• Force tolerance (fmax) such as 0.02, 0.005, or 0.0001 eV/A.
• Maximum relaxation steps.
• Atom-only or atom-plus-cell relaxation.
• Optimizer and cell filter.
• Optional advanced lines such as nequip_model_path=..., constrain_symmetry=false, or mattersim_runner=ase.

Access And Computing Limits

This is a computing-intensive app and requires login. Free daily CIF limits are counted after archive expansion: unverified users can submit 3 CIFs per day, verified non-academic users can submit 10 CIFs per day, and verified academic users can submit 50 CIFs per day. Submissions above the daily free limit consume computing credits when credits are available.

Method

The app reads each CIF with ASE, attaches the selected ML potential, and runs an ASE relaxation. MatterSim can run through ASE optimizers or the MatterSim Relaxer path. NequIP uses a compiled ASE model file, typically stored under model_store/nequip/.

Local Docker builds install MatterSim by default so MatterSim relaxation is ready for local use. NequIP remains optional locally because it also needs a compiled ASE model artifact. Remote Ubuntu deployments install both MatterSim and NequIP through update_server.sh, which exports MTOOLBOX_INSTALL_MATTERSIM=true and MTOOLBOX_INSTALL_NEQUIP=true before the backend rebuild.

Output

• structure-relaxation-results.csv with filename, formula, status, engine, device, optimizer, final energy, final energy per atom, final max force, cell parameters, and volume change.
• structure-relaxation-results.zip containing all relaxed CIFs and per-structure JSON summaries.
• structure-relaxation-summaries.json collecting every per-structure JSON summary in one file.
• structure-relaxation-manifest.csv describing loaded and skipped inputs.

How To Use The Result

Use the relaxed CIF ZIP as input for downstream screening such as phonon stability, energy diagnostics, MLIP-MD, elastic constants, or DFT setup. Use the CSV to quickly sort by final force, convergence status, energy per atom, and volume change.

Limitations

This is ML-potential relaxation, not final DFT validation. Tight fmax values such as 0.0001 eV/A can be slow and may not be meaningful if the ML potential is outside domain. NequIP requires a compiled ASE model artifact whose compile device should match the runtime device. Final publication-quality structures should be validated with DFT or experiment.

Example Input

Upload CIF files or a CIF archive
relaxation_model=mattersim
device=auto
fmax=0.02
steps=500
relax_cell=true
optimizer=FIRE
cell_filter=FrechetCellFilter