Molecular dynamics with multiple time scales: The selection of efficient reference system propagators

Several heuristic rules are developed to assist in the implementation of the reversible reference system propagator algorithm (rRESPA). This is done through the use of examples, illustrating the use of properly chosen rRESPA splits of various types, as well as the dangers associated with improperly chosen ones. It is concluded that a particle-based rRESPA split should be used only when there is a great disparity in particle masses, and that a force-based split should be used only when there is no persisting opposition between forces in the system which are integrated with different time steps.