Dynamical lattice gases and inherent structure in condensed phases

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Abstract
The nature of structural order and basic kinetic processes in condensed phases theoretically can be clarified by quenching to mechanically stable particle packings, the relevant ‘‘inherent structure’’. Numerically locating these potential energy minima in realistic models for various substances is often a very demanding task. A class of many-body systems, ‘‘dynamical lattice gases,’’ is introduced for which the steepest-descent quenching is particularly simple. The resulting packings place particles on sites of a regular array, the distribution of energies of those packings can be obtained from the solution of a related Ising model, and transition states between interconvertible packings are trivial to locate. Some elementary analytical results have been obtained for vibrational free energies of the packings. Some versions of these models, notably the quarter-filled face-centered-cubic case, are well suited for study of liquid-phase supercooling and formation of low-temperature amorphous solids.