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arXiv · 2406.00513

Kernel-based Minimal Distributed Charges: A Conformationally Dependent ESP-Model for Molecular Simulations

Eric Boittier·Kai Töpfer·Mike Devereux·Markus Meuwly
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Abstract

A kernel-based method (kernelized minimal distributed charge model - kMDCM) to represent the molecular electrostatic potential (ESP) in terms of off-center point charges whose positions adapts to the molecular geometry. Using Gaussian kernels and atom-atom distances as the features, the ESP for water and methanol is shown to improve by at least a factor of two compared with point charge models fit to an ensemble of structures. Combining kMDCM for the electrostatics and reproducing kernels for the bonded terms allows energy-conserving simulation of 2000 water molecules with periodic boundary conditions on the nanosecond time scale.

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Eric Boittier, Kai Töpfer, Mike Devereux, Markus Meuwly. 2024-06-01. Kernel-based Minimal Distributed Charges: A Conformationally Dependent ESP-Model for Molecular Simulations. https://arxiv.org/abs/2406.00513

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