AN EVALUATION OF THE GAUSS-RADAU ALGORITHM FOR THE SIMULATION OF CHEMICAL-DYNAMICS

The Verlet, Verlet leap frog, Gear fixed time step, Gear variable time step, Runge-Kutta, and Gauss-Radau algorithms have been compared using trajectory data obtained from the integration of a one-dimensional diatomic chain under constant pressure. Investigation into the times of local and normal mode relaxation and conservation of the constants of the motion facilitated comparison of the integration techniques. It has been found that the Gauss-Radau algorithm, which is not widely used in the simulation of chemical dynamics, generally affords a higher accuracy at an improved efficiency. (C) 1994 Academic Press, Inc.