Modulated structures for incommensurate monolayer solid phases ofD2physisorbed on graphite

Abstract

Neutron and low-energy electron diffraction at 2≤T≤5 K are used to determine the structure of three incommensurate (IC) solid phases for ${\mathrm{D}}_2$ on graphite. The α phase is a uniaxial IC solid phase with striped domain walls due to strong substrate-induced modulation of the nearest-neighbor spacing. The γ phase is a rotated triangular IC phase with satellite diffraction peaks due to modulation intermediate between that of the α phase and the Novaco-McTague rotated IC phase which exists at higher density.