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arXiv · 2005.10736

Stochastic Constrained Extended System Dynamics for Solving Charge Equilibration Models

Songchen Tan·Itai Leven·Dong An·Lin Lin·Teresa Head-Gordon
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Abstract

We present a new stochastic extended Lagrangian solution to charge equilibration that eliminates self-consistent field (SCF) calculations, eliminating the computational bottleneck in solving the many-body solution with standard SCF solvers. By formulating both charges and chemical potential as latent variables, and introducing a holonomic constraint that satisfies charge conservation, the SC-XLMD method accurately reproduces structural, thermodynamic, and dynamics properties using ReaxFF, and shows excellent weak- and strong-scaling performance in the LAMMPS molecular simulation package.

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Songchen Tan, Itai Leven, Dong An, Lin Lin, Teresa Head-Gordon. 2020-05-21. Stochastic Constrained Extended System Dynamics for Solving Charge Equilibration Models. https://arxiv.org/abs/2005.10736

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