Physics-Informed and Equivariant Machine Learning for Molecular Dipole Moment Prediction
1Department of Chemistry, University of Zurich, Zurich, CH-8057, Switzerland. ke.chen2@chem.uzh.ch.
Chimia
|June 1, 2026
Summary
Physics-informed machine learning models, incorporating charge equilibrium equations (QEq), slightly outperform direct equivariant methods for predicting molecular electric dipole moments, especially for long-range interactions.
Area of Science:
- Computational Chemistry
- Machine Learning in Chemistry
- Quantum Mechanics
Background:
- Accurate prediction of molecular electric dipole moments is essential for understanding molecular behavior and reactivity.
- Equivariant machine learning models offer direct vector prediction of electric dipole moments.
- The necessity of integrating physics-based principles, like charge equilibrium, into these models remains an open question.
Purpose of the Study:
- To systematically compare direct equivariant electric dipole moment prediction with physics-informed, charge-based approaches.
- To evaluate model performance across diverse chemical datasets, including varying interaction ranges.
- To assess the impact of physics integration on model interpretability and transferability.
Main Methods:
- Employed the MACE (Machine-learning Atomic力) framework for both direct equivariant prediction and a charge-based approach.
- Integrated a variant of the charge equilibrium equation (QEq) into the MACE framework for physics-informed modeling.
- Tested models on QM7b, QM9, SPICE, and SN2 datasets, covering short-to-long range interactions.
Main Results:
- Both direct equivariant prediction and the physics-informed QEq approach demonstrated good performance on short-to-medium range interaction datasets.
- The charge-based QEq model exhibited slightly superior performance compared to direct prediction, particularly with larger training datasets.
- The QEq model significantly outperformed direct prediction for systems involving long-range interactions.
Conclusions:
- Physics-informed machine learning models, specifically the QEq approach, offer advantages in predicting molecular electric dipole moments.
- The integration of physics enhances model performance, especially for complex systems with long-range interactions.
- Incorporating physics is crucial for improving model interpretability and transferability in molecular property prediction.
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