Phonons and librational excitations in solid CD4I and CD4II
- 28 October 1977
- journal article
- Published by IOP Publishing in Journal of Physics C: Solid State Physics
- Vol. 10 (20), 3959-3969
- https://doi.org/10.1088/0022-3719/10/20/005
Abstract
Acoustic phonon dispersion curves have been measured by neutron inelastic scattering in phases I and II of solid deuteromethane (CD4), yielding elastic constants CII=3.08+or-0.20, C12=2.14+or-0.24 and C44=1.58+or-0.06 (in units of 1010 dyn cm-2) in phase I. The elastic constants in phase II are about 10% higher. Longitudinal acoustic phonons in the (111) direction indicate life-time broadening. While no well defined librational excitations were observed, there is evidence that inelastic 'shoulders' in the neutron spectra are due to damped librations.Keywords
This publication has 12 references indexed in Scilit:
- Librational excitations in ordered and in partially ordered molecular crystalsThe Journal of Chemical Physics, 1976
- CH4: Tunneling states, rotations, and phase transition in a quantum molecular crystalSolid State Communications, 1975
- Phonon dispersion in solid DC1 ISolid State Communications, 1975
- Librational excitations in phase II of solid CPhysical Review B, 1974
- Critical Slowing Down of Orientational Fluctuations in a Plastic CrystalPhysical Review Letters, 1974
- Critical Scattering in Solid CPhysical Review Letters, 1972
- Structure and Phase Transitions of Solid Heavy Methane (CD4)The Journal of Chemical Physics, 1972
- A method of predicting line shapes in three-axis spectrometryActa Crystallographica Section A, 1971
- The elastic constants of solid CD4—I from neutron measurementsSolid State Communications, 1971
- The resolution function in neutron diffractometry. I. The resolution function of a neutron diffractometer and its application to phonon measurementsActa Crystallographica, 1967