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arXiv · 2006.09250

Pressure control using stochastic cell rescaling

Mattia Bernetti·Giovanni Bussi
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Abstract

Molecular dynamics simulations require barostats to be performed at constant pressure. The usual recipe is to employ the Berendsen barostat first, which displays a first-order volume relaxation efficient in equilibration but results in incorrect volume fluctuations, followed by a second order or Monte Carlo barostat for production runs. In this paper, we introduce stochastic cell rescaling, a first-order barostat that samples the correct volume fluctuations by including a suitable noise term. The algorithm is shown to report volume fluctuations compatible with the isobaric ensemble and its anisotropic variant is tested on a membrane simulation. Stochastic cell rescaling can be straightforwardly implemented in existing codes and can be used effectively both in equilibration and in production phases.

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Mattia Bernetti, Giovanni Bussi. 2020-06-16. Pressure control using stochastic cell rescaling. https://doi.org/10.1063/5.0020514

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