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arXiv · 2603.28518

Structured force reformulation of many-body dispersion: towards effective atom--atom decomposition and surrogate modeling

Zhaoxiang Shen·Raúl I. Sosa·Stéphane P. A. Bordas·Alexandre Tkatchenko·Jakub Lengiewicz
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Abstract

We present a structured force reformulation of the many-body dispersion (MBD) model that enables a physically consistent decomposition of forces into pairwise components. By introducing a many-body correlation matrix that scales dipole--dipole interactions, we derive unified expressions for the MBD energy, force, and Hessian. This reformulation reveals a natural structure for effective atom--atom force decomposition and provides a promising foundation for interpretable analysis and machine learning surrogate modeling of MBD interactions.

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Zhaoxiang Shen, Raúl I. Sosa, Stéphane P. A. Bordas, Alexandre Tkatchenko, Jakub Lengiewicz. 2026-04-11. Structured force reformulation of many-body dispersion: towards effective atom--atom decomposition and surrogate modeling. https://arxiv.org/abs/2603.28518

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