A stochastic Trotter integration scheme for dissipative particle dynamics.

Departamento de Física Fundamental, UNED, Avda. Senda del Rey 9, 28040 Madrid, Spain; Centre for Computational Science, Department of Chemistry, University College London, 20 Gordon Street, WC1H 0AJ London, UK
Mathematics and Computers in Simulation 01/2006; 72:190-194. DOI: 10.1016/j.matcom.2006.05.019
Source: DBLP

ABSTRACT In this article we show in detail the derivation of an integration scheme for the dissipative particle dynamic model (DPD) using the stochastic Trotter formula [G. De Fabritiis, M. Serrano, P. Español, P.V. Coveney, Phys. A 361 (2006) 429]. We explain some subtleties due to the stochastic character of the equations and exploit analyticity in some interesting parts of the dynamics. The DPD–Trotter integrator demonstrates the inexistence of spurious spatial correlations in the radial distribution function for an ideal gas equation of state. We also compare our numerical integrator to other available DPD integration schemes.

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