Monte Carlo simulation of an argon cluster confined in zeolite NaCaA

A Monte Carlo simulation of a thirteen-atom argon cluster in supercages of zeolite NaCaA is reported. The confined cluster undergoes distortion giving a peak in the angle distribution function at around 90°. The structure, energetics and other properties are dictated by a competition between guest-guest and guest-zeolite interactions. It is found that the cluster melts in the region from 25 to 40 K. The change in δ during melting is smaller than that observed for bulk matter or that for the free cluster, which we attribute to confinement.