  A new Langevin-Verlet thermostat that preserves the fluctuation-dissipation
relationship for discrete time steps, is applied to molecular modeling and
tested against several popular suites (AMBER, GROMACS, LAMMPS) using a small
molecule as an example that can be easily simulated by all three packages.
Contrary to existing methods, the new thermostat exhibits no detectable changes
in the sampling statistics as the time step is varied in the entire numerical
stability range. The simple form of the method, which we express in the three
common forms (Velocity-Explicit, Stormer-Verlet, and Leap-Frog), allows for
easy implementation within existing molecular simulation packages to achieve
faster and more accurate results with no cost in either computing time or
programming complexity.
