Generalized-Ensemble Algorithms for Simulations of Complex Molecular Systems

Abstract

In molecular simulations of complex systems with many degrees of freedom, conventional Monte Carlo and molecular dynamics simulations in canonical ensemble or isobaric-isothermal ensemble suffer from a great difficulty, in which simulations tend to get trapped in states of energy local minima. A simulation in generalized ensemble performs a random walk in specified variables and overcomes this difficulty. In this chapter, we review the generalized-ensemble algorithms. Replica-exchange method, multicanonical algorithm, and their extensions are described. Some simulation results based on these generalized-ensemble algorithms are also presented.