9727714 Landau This is a renewal grant to a senior computational physicist to conduct a series of simulations of condensed matter systems. Computer simulations represent a powerful tool for obtaining fundamental information about wide ranging problems in statistical physics and can complement traditional theoretical and experimental approaches. This research will continue development and refinement of large scale simulation methods for the study of phase transitions in systems which are difficult to treat analytically. The techniques to be used include diverse Monte Carlo and spin dynamics simulations. Models are expected to be relevant to magnetic materials, cubic binary alloys, adsorbed atoms on crystalline substrates, and disordered media. Several of the problems include particles which may move continuously in space and which are subject to elastic interactions, whereas other problems will be confined to rigid lattices (including classical spins with continuous degrees of freedom) with discrete near neighbor interactions. In many of the systems finite geometries and/or the presence of walls are responsible for behavior which is different than that which is observed in the bulk. Both static and dynamic critical phenomena for systems in equilibrium will be carefully examined. Simple non-equilibrium models of film growth will be studied using kinetic Monte Carlo methods. %%% This is a renewal grant to a senior computational physicist to conduct a series of simulations of condensed matter systems. Computer simulations represent a powerful tool for obtaining fundamental information about wide ranging problems in statistical physics and can complement traditional theoretical and experimental approaches. This research will continue development and refinement of large scale simulation methods for the study of phase transitions in systems which are difficult to treat analytically. The techniques to be used include diverse Monte Carlo and spin dynamics si mulations. Models are expected to be relevant to magnetic materials, cubic binary alloys, adsorbed atoms on crystalline substrates, and disordered media. ***