Energy-based Error Control Strategies Suitable

Energy-Based Error Control Strategies Suitable for Long MD Simulations Kante Easley Master of Science Graduate Department of Computer Science University of Toronto 2009 When evaluating integration schemes used in molecular dynamics (MD) simulations, energy conservation is often cited as the primary criterion by which the integrators should be compared. As a result variable stepsize Runge-Kutta methods are often ruled out of consideration due to their characteristic energy drift. We have shown that by appropriately modifying the stepsize selection strategy in a variable stepsize RK method it is possible for the MD practitioner to obtain substantial control over the energy drift during the course of a simulation. This ability has been previously unreported in the literature, and we present numerical examples to illustrate that it can be achieved without sacrificing computational efficiency under currently obtainable timescales.