Non-Hamiltonian molecular dynamics implementation of the Gibbs ensemble method. I. Algorithm

摘要

In this paper (paper I) and the following paper (paper II) [C. Bratschi, H. Huber, and D. J. Searles, J. Chem. Phys. 126, 164105 (2007)], a new molecular dynamics algorithm implementing the Gibbs ensemble will be presented and then on applied to the liquid-vapor coexistence curve for two ab initio CO2 potentials. In paper I, the Gibbs ensemble molecular dynamics algorithm using non-Hamiltonian molecular dynamics techniques is introduced. It is shown that states of the correct probability density function are sampled and the correct exchange probability is generated. The extended system Nose-Hoover formalism is used to generate a constant temperature ensemble with equal pressures in the subsystems, combined with single particle transfers between the subsystems, over several time steps, to get equal chemical potentials. (c) 2007 American Institute of Physics.