Predicted properties and melting transition of krypton layers physisorbed onto Lennard-Jones spheres

We report the results of constant-temperature, constant-density, molecular- dynamics simulations of the melting transition of Kr atoms physisorbed onto small Lennard-Jones spheres. Adlayer depletion takes place when free bound ary conditions are used but utilization of a soft reflecting shell results in a broad melting transition at around T=65K without any appreciable hyste resis. We introduce structural and bond-orientational parameters and utiliz e thermodynamic parameters to monitor the behavior of the system; The spher ical geometry causes compression of the neighbor distances with respect to those for the corresponding planar case, causing enhanced interaction of th e neighbor shells via interstitials/vacancies, the nature of which is furth er elucidated using the bond-orientational information. Quantities related to the radial degree of freedom change slowly during melting, and bond-orie ntational order of the Kr lattice persists well into the fluid.