Initial support for FAIRChem calculator

README.md

@@ -33,13 +33,13 @@ uv sync
 
 ```python
 from ase.build import bulk
-from pyslice import MDCalculator,MultisliceCalculator,TACAWData
+from pyslice import ORBMDCalculator,MultisliceCalculator,TACAWData
 
 # 1. Create structure
 atoms = bulk("Si", "diamond", a=5.431, cubic=True) * (10, 10, 2)
 
 # 2. Run molecular dynamics
-md = MDCalculator(model_name="orb-v3-direct-inf-omat")
+md = ORBMDCalculator(model_name="orb-v3-direct-inf-omat")
 md.setup(atoms, temperature=300, timestep=2.0, production_steps=500, save_interval=5)
 trajectory = md.run()
 
@@ -123,8 +123,8 @@ wf_data.plot(powerscaling=0.125)  # Diffraction pattern
 ```
 Input Sources          Processing              Analysis            Output
 ─────────────────────────────────────────────────────────────────────────────
-CIF / XYZ / LAMMPS ─┬─→ Loader ─┬─→ MDCalculator ─┐
-ASE Atoms / .traj  ─┘           │   (ORB, MACE)   │
+CIF / XYZ / LAMMPS ─┬─→ Loader ─┬─→ ORBMDCalculator ─┐
+ASE Atoms / .traj  ─┘           │   (or FAIRChem)    │
                                 │                 ↓
                                 └───────────→ Trajectory
                                                   │
@@ -159,13 +159,13 @@ traj = Loader("file.cif").load()
 traj = Loader("dump.lammpstrj", timestep=0.01, atom_mapping={1: "B", 2: "N"}).load()
 ```
 
-### `MDCalculator`
+### `ORBMDCalculator` / `FAIRChemMDCalculator`
 Run molecular dynamics with universal ML potentials.
 
 ```python
-from pyslice.md import MDCalculator
+from pyslice.md import ORBMDCalculator
 
-md = MDCalculator(model_name="orb-v3-direct-inf-omat", device="cuda")
+md = ORBMDCalculator(model_name="orb-v3-direct-inf-omat", device="cuda")
 md.setup(
     atoms,
     temperature=300,        # K

examples/k_space_tmdc_showcase_pub.py

@@ -17,7 +17,7 @@
 import numpy as np
 from ase.build import make_supercell, mx2
 
-from pyslice import Loader, MDCalculator, MultisliceCalculator, TACAWData
+from pyslice import Loader, ORBMDCalculator, MultisliceCalculator, TACAWData
 
 # =============================================================================
 # CONFIGURATION
@@ -68,7 +68,7 @@ def run_md(atoms, output_dir: Path):
     if SKIP_MD and traj_file.exists():
         return Loader(filename=str(traj_file), timestep=timestep_ps).load()
 
-    md = MDCalculator(
+    md = ORBMDCalculator(
         model_name="orb-v3-conservative-inf-omat",
         weights_path=CACHED_WEIGHTS_PATH,
     )

examples/molecular_dynamics.py

@@ -14,7 +14,7 @@
 
 import os
 from ase.build import bulk
-from pyslice import MDCalculator, Trajectory, analyze_md_trajectory
+from pyslice import ORBMDCalculator, Trajectory, analyze_md_trajectory
 
 os.makedirs("outputs/md_demo", exist_ok=True)
 os.makedirs("outputs/md_production", exist_ok=True)
@@ -35,7 +35,7 @@
 # ---------------------------------------------------------------------------
 # 2. Set up the MD calculator with an ORB potential
 # ---------------------------------------------------------------------------
-md = MDCalculator(model_name="orb-v3-conservative-inf-omat")
+md = ORBMDCalculator(model_name="orb-v3-conservative-inf-omat")
 
 md.setup(
     atoms=atoms,
@@ -120,7 +120,7 @@
 #              production_relaxation_steps lets the system forget the
 #              thermostat kick before recording begins.
 #
-md_prod = MDCalculator(model_name="orb-v3-conservative-inf-omat")
+md_prod = ORBMDCalculator(model_name="orb-v3-conservative-inf-omat")
 
 md_prod.setup(
     atoms=atoms_prod,

examples/real_space_phonon_showcase_pub.py

@@ -18,7 +18,7 @@
 from ase import Atoms
 from ase.build import bulk, surface
 
-from pyslice import Loader, MDCalculator, MultisliceCalculator, TACAWData
+from pyslice import Loader, ORBMDCalculator, MultisliceCalculator, TACAWData
 
 # =============================================================================
 # CONFIGURATION
@@ -123,7 +123,7 @@ def run_md(atoms, output_dir: Path, save_interval: int):
     atoms.calc = ORBCalculator(orb)
     FIRE(atoms, logfile=str(output_dir / "relax.log")).run(fmax=0.05, steps=500)
 
-    md = MDCalculator(
+    md = ORBMDCalculator(
         model_name="orb-v3-conservative-inf-omat",
         weights_path=CACHED_WEIGHTS_PATH,
     )

examples/tacaw_pipeline.py

@@ -15,7 +15,7 @@
 import numpy as np
 import matplotlib.pyplot as plt
 from ase.build import bulk
-from pyslice import MDCalculator, MultisliceCalculator, TACAWData
+from pyslice import ORBMDCalculator, MultisliceCalculator, TACAWData
 
 os.makedirs("outputs", exist_ok=True)
 
@@ -29,7 +29,7 @@
 # ---------------------------------------------------------------------------
 # 2. Run molecular dynamics with an ORB machine-learning potential
 # ---------------------------------------------------------------------------
-md = MDCalculator(model_name="orb-v3-conservative-inf-omat")
+md = ORBMDCalculator(model_name="orb-v3-conservative-inf-omat")
 
 md.setup(
     atoms=atoms,

src/pyslice/md/__init__.py

@@ -1,9 +1,9 @@
 """
 Molecular dynamics module for PySlice.
 
-Provides MD simulation capabilities using machine learning force fields (ORB models).
+Provides MD simulation capabilities using machine learning force fields.
 """
 
-from .molecular_dynamics import MDCalculator, MDConvergenceChecker, analyze_md_trajectory
+from .molecular_dynamics import MDCalculator, ORBMDCalculator, FAIRChemMDCalculator, MDConvergenceChecker, analyze_md_trajectory
 
-__all__ = ['MDCalculator', 'MDConvergenceChecker', 'analyze_md_trajectory']
+__all__ = ['MDCalculator', 'ORBMDCalculator', 'FAIRChemMDCalculator', 'MDConvergenceChecker', 'analyze_md_trajectory']