Multiple time scale methods for constant pressure molecular dynamics simulations of molecular systems

An efficient integration scheme is proposed based on the reversible reference system propagator algorithm (r-RESPA) for the molecular dynamics simulation of molecular solids or liquids at constant pressure. Starting from the Parrinello-Rhaman Lagrangian, the algorithm has been obtained using a Trotter factorization for the classical propagator. This r-RESPA scheme allows us to simulate efficiently the dynamics of completely flexible molecules in the condensed phases, under the constraint of constant pressure. The method may find potential application in the study of mesophases such as nematic or plastic crystals, or in studying the effect of pressure on the spectral properties of solids.