Mathematical Problems in Engineering
Volume 2009 (2009), Article ID 215815, 14 pages
Review Article

Simulation Algorithm That Conserves Energy and Momentum for Molecular Dynamics of Systems Driven by Switching Potentials

Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia

Received 26 November 2008; Revised 10 March 2009; Accepted 28 May 2009

Academic Editor: Jerzy Warminski

Copyright © 2009 Christopher G. Jesudason. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Whenever there exists a crossover from one potential to another, computational problems are introduced in Molecular Dynamics (MD) simulation. These problem are overcome here by an algorithm, described in detail. The algorithm is applied to a 2-body particle potential for a hysteresis loop reaction model. Extreme temperature conditions were applied to test for algorithm effectiveness by monitoring global energy, pressure and temperature discrepancies in an equilibrium system. No net rate of energy and other flows within experimental error should be observed, in addition to invariance of temperature and pressure along the MD cell for the said system. It is found that all these conditions are met only when the algorithm is applied. It is concluded that the method can easily be extended to Nonequilibrium MD (NEMD) simulations and to reactive systems with reversible, non-hysteresis loops.