A new, effective method for computing the interaction potential of hard cyclic multimer systems

Studies of effiiency of several methods for calculating the interaction potential of a pair of two-dimensional hard cyclic multimers - molecules formed by hard disks (atoms) placed at the vertices of a regular polygon - are reported in this work. Such hard-body particles, known as hard cyclic multimers, constitute a class of important reference systems in modeling structural and thermodynamic properties of molecular systems. A new method is proposed which can be easily implemented to Monte Carlo simulations of two-dimensional cyclic multimers and which is faster than the fastest method used previously.