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arXiv · 1605.01654

Geometric integrator for simulations in the canonical ensemble

Diego Tapias·David P. Sanders·Alessandro Bravetti
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Abstract

In this work we introduce a geometric integrator for molecular dynamics simulations of physical systems in the canonical ensemble. In particular, we consider the equations arising from the so-called density dynamics algorithm with any possible type of thermostat and provide an integrator that preserves the invariant distribution. Our integrator thus constitutes a unified framework that allows the study and comparison of different thermostats and of their influence on the equilibrium and non-equilibrium (thermo-)dynamic properties of the system. To show the validity and the generality of the integrator, we implement it with a second-order, time-reversible method and apply it to the simulation of a Lennard-Jones system with three different thermostats, obtaining good conservation of the geometrical properties and recovering the expected thermodynamic results.

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Diego Tapias, David P. Sanders, Alessandro Bravetti. 2016-05-05. Geometric integrator for simulations in the canonical ensemble. https://doi.org/10.1063/1.4961506

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