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Stochastic Constrained Extended System Dynamics for Solving Charge Equilibration Models

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 نشر من قبل Teresa Head-Gordon
 تاريخ النشر 2020
  مجال البحث فيزياء
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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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