Dynamics of intercalated molecules. Part 4.—Neutron inelastic scattering from methane in C28Cs(CH4)

Abstract

The neutron inelastic scattering from methane sorbed by second-stage graphite–caesium, C₂₈Cs, has been measured between 10 and 170 K. The molecular excitation spectrum is relatively featureless, in agreement with simulation of the scattering law by molecular dynamics. This arises because of the low symmetry and the anharmonicity of the sorption site potential and strong coupling between translational and rotational motions. The most suitable sorption potential is determined by matching the calculated and experimental maxima in the inelastic spectrum.