Structure determination for the intermediate-densityS2monolayer phase of ethane physisorbed on graphite

Abstract

Low-energy electron diffraction has been used to determine the unit mesh of the intermediate-density $S_2$ monolayer phase of ethane physisorbed on graphite at 40 K. The proposed unit mesh is rectangular with sides 7.39±0.07 and 5.24±0.05 Å. The short side is rotated 5.7°±0.2° with respect to the graphite unit mesh. Analysis of published neutron-diffraction data indicates that $S_2$ is a herringbone structure with two molecules per unit mesh.