Overview
- Field: Machine Learning / AI for Science
- Authors: Gil Harari, Yoel Zimmermann, Ola Tangen Kulseng, Laura Zichi, Chuin Wei Tan, Marc L. Descoteaux, Boris Kozinsky
- Published: 2026-07-02
- arXiv: 2607.02499
- Categories: cs.LG, cs.AI, physics.chem-ph, physics.comp-ph
- Optimizer choice for MLIP training is underexplored; Adam has been the default.
- Matrix-structured optimizers (Muon, SOAP, SOAP-Muon) beat Adam in convergence speed and final accuracy.
- SOAP and SOAP-Muon are the most robust and consistently strong choices; Muon alone gives only partial gains.
- Gains are especially significant with partial force supervision, enabling more label-efficient training.
Summary (translated)
Machine learning interatomic potentials (MLIPs) have become a hallmark of AI for scientific simulation. While efforts on new architectures and datasets have led to increasingly accurate and general models, the choice of optimizer for training has largely remained unexplored, defaulting to Adam and its variants in the community. Here, we implement and systematically compare a class of recently proposed matrix-structured optimizers, including Muon, SOAP, and the hybrid SOAP-Muon, for training NequIP and Allegro MLIP models. We find that these optimizers can substantially outperform Adam in both convergence speed and final accuracy. SOAP and SOAP-Muon emerge as robust and consistently strong methods, while Muon only provides partial gains relative to Adam. The improvements are particularly pronounced under partial force supervision. Our results indicate that optimizer choice is an overlooked yet impactful design dimension for MLIPs.