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arXiv · 0802.2421

New fitting scheme to obtain effective potential from Car-Parrinello molecular dynamics simulations: Application to silica

Antoine Carre·Juergen Horbach·Simona Ispas·Walter Kob
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Abstract

A fitting scheme is proposed to obtain effective potentials from Car-Parrinello molecular dynamics (CPMD) simulations. It is used to parameterize a new pair potential for silica. MD simulations with this new potential are done to determine structural and dynamic properties and to compare these properties to those obtained from CPMD and a MD simulation using the so-called BKS potential. The new potential reproduces accurately the liquid structure generated by the CPMD trajectories, the experimental activation energies for the self-diffusion constants and the experimental density of amorphous silica. Also lattice parameters and elastic constants of alpha-quartz are well-reproduced, showing the transferability of the new potential.

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Antoine Carre, Juergen Horbach, Simona Ispas, Walter Kob. 2008-02-18. New fitting scheme to obtain effective potential from Car-Parrinello molecular dynamics simulations: Application to silica. https://doi.org/10.1209/0295-5075%2F82%2F17001

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