The Novaco-McTague rotated Xe monolayer on Pt(111): A high-order commensurate locked phase

The structural analysis of the physisorption system Xe/Pt(111) by means of high-resolution helium diffraction shows that the Xe monolayer exhibits a variety of structural phases: commensurate, incommensurate and incommensurate rotated. The observed buckling of the rotated phase demonstrates that a fraction of the Xe atoms is locked in high symmetry sites in agreement with the theoretical coincident site lattice concept of Fuselier et al., i.e. the rotated phase is a higher-order commensurate phase.