cliffordip 0.1.1

CliffordIP: Clifford Algebra Equivariant Interatomic Potentials for Heterogeneous Catalysis

CliffordIP: Clifford Algebra Equivariant Interatomic Potentials for Heterogeneous Catalysis

Equivariant GNN for machine learning interatomic potentials (MLIPs) built on Clifford algebra Cl(3,0). Targets OC20, OC22, QM9, MD17, and any custom dataset via a plugin registry.

Installation

# Core (Clifford algebra + model + Lightning trainer)
pip install cliffordip

# With OC20/OC22 dataset support
pip install "cliffordip[oc20]"

# Development install (editable, all extras)
pip install -e ".[dev]"

# With uv (recommended)
uv pip install -e ".[dev]"

Quickstart

from cliffordip import CliffordIPWrapper, test_equivariance

# Verify O(3) equivariance is intact
test_equivariance()

# Build a model directly
model = CliffordIPWrapper(
    n_channels=52,
    n_interactions=5,
    cutoff=6.0,
    n_rbf=50,
    max_neighbors=50,
)

Training

Training uses PyTorch Lightning via the cliffordip-train CLI:

# Fit on OC20 S2EF
cliffordip-train fit \
    --config src/cliffordip/configs/dataset/oc20_s2ef.yaml \
    --trainer.max_epochs 10 \
    --trainer.precision bf16-mixed \
    --trainer.devices 4

# Override any parameter
cliffordip-train fit \
    --config src/cliffordip/configs/dataset/oc20_s2ef.yaml \
    --model.n_channels 64 \
    --data.cfg.training.batch_size 32

Supported trainer features (via Lightning)

Feature	Config
BF16 mixed precision	--trainer.precision bf16-mixed
Multi-GPU (DDP)	--trainer.devices N --trainer.strategy ddp
Gradient clipping	--trainer.gradient_clip_val 1.0
Gradient accumulation	--trainer.accumulate_grad_batches 4
EMA weights	Add EMACallback(decay=0.999)
W&B logging	Add WandbLogger(project="mlip")
Checkpointing	Built-in ModelCheckpoint callback
Early stopping	Built-in EarlyStopping callback

Python API

import lightning as L
from cliffordip.lightning import CliffordIPLightningModule, CliffordIPDataModule, EMACallback
from cliffordip.train.config_utils import load_config

cfg = load_config(["dataset.name=oc20_s2ef", "model.name=clifford"])

module = CliffordIPLightningModule(cfg)
datamodule = CliffordIPDataModule(cfg)

trainer = L.Trainer(
    max_epochs=10,
    precision="bf16-mixed",
    gradient_clip_val=1.0,
    callbacks=[EMACallback(decay=0.999)],
)
trainer.fit(module, datamodule)

Supported Datasets

Dataset	Extra	Name
OC20 S2EF / IS2RE	[oc20]	oc20_s2ef, oc20_is2re
OC22 S2EF / IS2RE	[oc22]	oc22_s2ef, oc22_is2re
QM9	[qm9]	qm9
MD17	[md17]	md17 (+ molecule config)

Adding a New Dataset

1. Create src/cliffordip/data/mydata.py with a @register_dataset("mydata") decorated factory
2. Add src/cliffordip/configs/dataset/mydata.yaml with dataset defaults
3. Add dependencies to pyproject.toml optional extras
4. Add from cliffordip.data import mydata # noqa to src/cliffordip/data/__init__.py

Baseline Models

Baseline implementations (PaiNN, NequIP, SchNet, DimeNet++, EquiformerV2, GotenNet, TorchMD-Net) live in baselines/ and are not included in the pip package — they are available in the GitHub repo for reproducibility only. To use them, clone the repo and add the root to your PYTHONPATH.

Architecture

Clifford algebra Cl(3,0)

8-dimensional multivectors with grades 0–3 (scalars, vectors, bivectors, pseudoscalar). Key design choices:

• Grade-sparse dispatch: Selects cheapest geometric product variant based on grade occupancy (~4× faster for early layers)
• Progressive grade activation: Early layers use only grades 0–1; higher grades unlock as the network deepens
• Zero-allocation forward: Pre-allocated multivector tensors, filled via index slices for torch.compile stability

Layer stack

1. src/cliffordip/clifford.py — Cl(3,0) primitives (CliffordIPLinear, CliffordIPNorm, CliffordIPGateActivation, CliffordIPGeometricProductLayer)
2. src/cliffordip/interaction.py — Message-passing GNN (RBF edge embedding, equivariant attention, multi-body interactions)
3. src/cliffordip/wrapper.py — Training wrapper (torch.compile, EMA, DeNS)
4. src/cliffordip/lightning/ — PyTorch Lightning LightningModule + LightningDataModule

Verifying Equivariance

from cliffordip import test_equivariance
test_equivariance()  # raises AssertionError if O(3) equivariance is broken