| Issue |
J. Phys. Colloques
Volume 42, Number C6, Décembre 1981
International Conference on Phonon Physics
|
|
|---|---|---|
| Page(s) | C6-584 - C6-586 | |
| DOI | https://doi.org/10.1051/jphyscol:19816170 | |
International Conference on Phonon Physics
J. Phys. Colloques 42 (1981) C6-584-C6-586
DOI: 10.1051/jphyscol:19816170
1 Department of Physics, University of Edinburgh, Scotland
2 Nuclear Physics Division, Bhabha Atomic Research Center, Bombay, India
3 I-4, Technical University of WrocŽaw, WrocŽaw, Poland
4 ILL, Grenoble, France
J. Phys. Colloques 42 (1981) C6-584-C6-586
DOI: 10.1051/jphyscol:19816170
INTERNAL AND EXTERNAL PHONONS IN MONOCLINIC TETRACYANOETHYLENE
S.L. Chaplot1, 2, A. Mierzejewski3, J. Lefebvre4, G.S. Pawley1 et T. Luty31 Department of Physics, University of Edinburgh, Scotland
2 Nuclear Physics Division, Bhabha Atomic Research Center, Bombay, India
3 I-4, Technical University of WrocŽaw, WrocŽaw, Poland
4 ILL, Grenoble, France
Abstract
Dispersion curves of 12 external and 10 internal phonon modes have been measured in the a*, b* and c* directions. The internal dispersion curves correspond to the 5 low-frequency vibrations of the free molecule and they exhibit a significant proportion of lattice mode character involving both translational and librational motions. Recent lattice dynamical calculations, in which several internal modes are included, have yielded neutron scattering cross-sections which have made possible to assign the observed molecular vibrations.