COMPUTATION OF COLLECTIVE MODES AND ACOUSTIC INVESTIGATIONS AT DIFFERENT TEMPERATURES OF VITREOUS SILICA

Citation
Rvg. Rao et R. Venkatesh, COMPUTATION OF COLLECTIVE MODES AND ACOUSTIC INVESTIGATIONS AT DIFFERENT TEMPERATURES OF VITREOUS SILICA, Pramana, 43(3), 1994, pp. 201-209
Citations number
31
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics
Journal title
ISSN journal
0304-4289
Volume
43
Issue
3
Year of publication
1994
Pages
201 - 209
Database
ISI
SICI code
0304-4289(1994)43:3<201:COCMAA>2.0.ZU;2-L
Abstract
This paper is mainly concerned with elastic and acoustic properties of vitrous silica besides the computation of phonon frequencies. Thus th e phonon frequencies of vitrous silica have been calculated assuming t he electronic bulk modulus, K(e), as equal to zero. New equations have been derived to relate the pressure derivatives of second order elast ic constants to the acoustic Gruneisen's parameters using both Bhatia- Singh's parameters and Schofield's equations. The calculated longitudi nal and transverse Gruneisen's parameters and the predicted absorption band spectra from Nagendranath's equation and Bhatia Singh's paramete rs are in good agreement with experiment. The calculated mean acoustic mode Gruneisen's parameter evaluated from the pressure derivative of Nagendranath's equation is also in good agreement with experiment.