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arXiv · 1601.01044

Sampling the isothermal-isobaric ensemble by Langevin dynamics

Xingyu Gao·Jun Fang·Han Wang
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Abstract

We present a new method of conducting molecular dynamics simulation in isothermal-isobaric ensemble based on Langevin equations of motion. The stochastic coupling to all particle and cell degrees of freedoms is introduced in a correct way, in the sense that the stationary configurational distribution is proved to be in consistent with that of the isothermal-isobaric ensemble. In order to apply the proposed method in computer simulations, a second order symmetric numerical integration scheme is developed by Trotter's splitting of the single-step propagator. Moreover, a practical guide of choosing working parameters is suggested for user specified thermo- and baro-coupling time-scales. The method and software implementation are carefully validated by a numerical example.

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Xingyu Gao, Jun Fang, Han Wang. 2016-04-27. Sampling the isothermal-isobaric ensemble by Langevin dynamics. https://doi.org/10.1063/1.4944909

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