Direct Evidence for Two-Dimensional Xe Gas-Solid Phase Transition on Pt(111) by Means of Thermal He Scattering

Abstract
Thermal He scattering is proposed as a method to investigate two-dimensional gas-solid phase transitions down to very low coverages (∼0.1%). The two-dimensional Xe gas-solid phase transition on a clean and defect-free Pt(111) surface is studied. The heat of vaporization of the two-dimensional solid phase into the two-dimensional ideal gas phase is 1.1±0.1 kcal/mole.