Structure of liquid and solid monolayer xenon on graphite

Abstract
An X-ray scattering study of xenon physi-adsorbed onto the (0001) surfaces of graphite is reported. Coverages between 0.3 and 2.0 monolayers are examined and unambiguous evidence is obtained for the existence of a 2D triple point at 99K. Above 99K incommensurate monolayer solid and liquid phases are observed. The liquid is well described by an exponential droplet model.