Effects of varying well-depth on the structure of binary assemblies of hard discs with a square-well potential

Abstract Binary assemblies of hard discs have been grown in a computer simulation following the method of Livesley and Loveday (1986). The pair potentials again included a square-well attractive part, but in this case the relative depths of the three kinds of wells have been chosen differently. The phase diagram of Livesley and Loveday and a phase diagram produced using an ordering of the relative depths of the pair-potential wells inverted with respect to theirs are compared. The constraint on the structure of the assembly arising from requirements of minimum local energy dominates that part of the geometric constraint arising from the proportions of the mixture if the two disc sizes are fairly similar, but the proportions place greater restrictions on the structure in other cases. The nature of the balance between the two constraints has been investigated by varying the relative depths of the potential wells in a systematic way. Attempts to use this model to generate quasicrystalline assemblies have been unsuccessful.