Faster Molecular Dynamics with Neural Network Potentials via Distilled Multiple Time-Stepping and Non-Conservative Forces
Nicolaï Gouraud, Côme Cattin, Thomas Plé, Olivier Adjoua, Louis Lagardère, Jean-Philip Piquemal
TL;DR
This work addresses the challenge of accelerating molecular dynamics with neural network potentials without sacrificing near-ab initio accuracy. It introduces DMTS-NC, a distilled non-conservative force model used in a dual-level RESPA-based MTS integrator, augmented by Hydrogen Mass Repartitioning and a runtime revert mechanism to maintain stability. The NC model is trained by distillation from a large FeNNix-Bio1(M) model, achieving an MAE of $1.46$ kcal/mol/Å and RMSE of $2.33$ kcal/mol/Å, and enabling larger external time steps while preserving sampling quality. Across bulk water and solvated proteins, DMTS-NC delivers substantial speedups (up to $\sim 431\%$ over STS and $\sim 31-16\%$ over conservative/fine-tuned DMTS) with minimal bias in structural and thermodynamic properties, illustrating a practical path toward deploying NN potentials in large-scale MD simulations.
Abstract
Following our previous work (J. Phys. Chem. Lett., 2026, 17, 5, 1288-1295), we propose the DMTS-NC approach, a distilled multi-time-step (DMTS) strategy using non conservative (NC) forces to further accelerate atomistic molecular dynamics simulations using foundation neural network models. There, a dual-level reversible reference system propagator algorithm (RESPA) formalism couples a target accurate conservative potential to a simplified distilled representation optimized for the production of non-conservative forces. Despite being non-conservative, the distilled architecture is designed to enforce key physical priors, such as equivariance under rotation and cancellation of atomic force components. These choices facilitate the distillation process and therefore improve drastically the robustness of simulation, significantly limiting the "holes" in the simpler potential, thus achieving excellent agreement with the forces data. Overall, the DMTS-NC scheme is found to be more stable and efficient than its conservative counterpart with additional speedups reaching 15-30% over DMTS. Requiring no finetuning steps, it is easier to implement and can be pushed to the limit of the systems physical resonances to maintain accuracy while providing maximum efficiency. As for DMTS, DMTS-NC is applicable to any neural network potential.
