Fluid-solid demixing in four and five dimensional asymmetric binary hard hypersphere mixtures.

Additive asymmetric binary mixtures of hard hyperspheres in four and five dimensions are investigated by Monte Carlo simulations. These investigations probe systems with diameter ratios of 0.4 and 0.5 in which the larger hyperspheres are dominant at a mole fraction of 3/4. At the lower densities, the equations of state compare well with molecular dynamics data and a variety of theoretical predictions. When the mixture enters the metastable, two-phase regime, the smaller hyperspheres exhibit unusual phenomena as the system density increases. To understand this behavior, the mean-square displacement at equilibrium from initial lattice positions, the various pair correlation functions, and occupancy numbers are calculated. In addition, the characteristics of an initially demixed system are studied.