Optimal symplectic integrators for molecular dynamics

The second-order velocity Verlet integrator is the most widely used symplectic integrator for molecular dynamics. We examine higher order symplectic integrators and access their performance with Lennard-Jones, and Yukawa potentials. We find that the optimized Verlet integrator which requires two force calculations per time step is the most efficient in most cases. In addition, we find that the performance of the integrators strongly depends on the accuracy of force calculation itself. We also discuss the performance of adaptive time steps.