Coherent neutron scattering response from glassy glycerol

Abstract

We report on inelastic neutron scattering measurements of fully deuterated glassy glycerol at temperatures between 15 K to 180 K. Incident energies of 40 and 100 meV and momentum transfers up to \ensuremath{\approxeq}12 A${\mathrm{\r{}}}^{\mathrm{\ensuremath{-}}1}$ were used. Analysis of the static structure factor calculated as the zeroth-frequency moment of S(Q,\ensuremath{\omega}) enabled us to derive valuable structural information on the intra- and intermolecular correlations. Generalized frequency distributions are derived from the spectra and are used to calculate the relevant thermodynamic properties of the material using a quasiharmonic approximation. Estimates are also made for the first order anharmonic effects. Some wave-vector-dependent effects, such as the reduced frequency moments of S(Q,\ensuremath{\omega}) are also evaluated, and their physical meaning discussed in some detail. \textcopyright{} 1996 The American Physical Society.