An adaptive mass algorithm for Car-Parrinello and Ehrenfest ab initio molecular dynamics

Ashraful Kadir; Mattias Sandberg; Anders Szepessy

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arXiv · 1409.4992

An adaptive mass algorithm for Car-Parrinello and Ehrenfest ab initio molecular dynamics

Ashraful Kadir·Mattias Sandberg·Anders Szepessy

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Abstract

Ehrenfest and Car-Parrinello molecular dynamics are computational alternatives to approximate Born-Oppenheimer molecular dynamics without solving the electron eigenvalue problem at each time-step. A non-trivial issue is to choose the artificial electron mass parameter appearing in the Car-Parrinello method to achieve both good accuracy and high computational efficiency. In this paper, we propose an algorithm, motivated by the Landau-Zener probability, to systematically choose an artificial mass dynamically, which makes the Car-Parrinello and Ehrenfest molecular dynamics methods dependent only on the problem data. Numerical experiments for simple model problems show that the time-dependent adaptive artificial mass parameter improves the efficiency of the Car-Parrinello and Ehrenfest molecular dynamics.

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Ashraful Kadir, Mattias Sandberg, Anders Szepessy. 2014-09-17. An adaptive mass algorithm for Car-Parrinello and Ehrenfest ab initio molecular dynamics. https://arxiv.org/abs/1409.4992

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