Isothermal-isobaric thermodynamics of small HgN clusters. A case study on Hg8

Abstract

Parallel-tempering Monte Carlo calculations have been performed for the Hg8 cluster in an isothermal-isobaric ensemble. Temperature and pressure dependent cluster residual heat capacity and Pearson correlation coefficient for cluster energy and volume have been calculated over a broad range of cluster temperatures and external pressures using a 2D multiple histogram method. Calculated data have subsequently been used in investigations of structural changes in Hg8 induced by increased pressure and temperature. A global picture of these changes is provided in the form of a cluster temperature-pressure phase diagram.