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DOE OSTI · 1838623

Stochastic Constrained Extended System Dynamics for Solving Charge Equilibration Models

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

In this work, we present a new stochastic extended Lagrangian molecular dynamics solution to charge equilibration that eliminates self-consistent field (SCF) calculations, thus eliminating the computational bottleneck in solving the charge distribution 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 thermodynamic, dynamic, and structural properties within the framework of ReaxFF for a bulk water system and highly reactive RDX molecules simulated at high temperature. The SC-XLMD method shows excellent computational performance and is available in the publicly available LAMMPS package.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYComputational chemistryEnergyMolecular dynamicsMolecular mechanicsPotential energy

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Tan, Songchen, Leven, Itai, An, Dong, Lin, Lin, Head-Gordon, Teresa. 2020-09-21. Stochastic Constrained Extended System Dynamics for Solving Charge Equilibration Models. https://doi.org/10.1021/acs.jctc.0c00514

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