Unusual structure in a quasi-two-dimensional binary colloid fluid

We have examined the character of the pair correlation functions of binary colloid mixtures in which the small particles can move in three dimensions but the large particles can move in only two dimensions. Our results provide evidence for unusually long-ranged spatial ordering of the dense large-sphere component of a quasi-two-dimensional binary colloid fluid for a particular ratio of concentrations of the small and large particles. This observation is rationalized by comparison with the results of simulations of the structure of a binary hard sphere fluid.