EVALUATION OF GRUNEISEN PARAMETERS, 3RD-ORDER ELASTIC-CONSTANTS, AND OTHER ASSOCIATED PROPERTIES OF AMORPHOUS AS

Citation
Rv. Gopala et R. Venkatesh, EVALUATION OF GRUNEISEN PARAMETERS, 3RD-ORDER ELASTIC-CONSTANTS, AND OTHER ASSOCIATED PROPERTIES OF AMORPHOUS AS, Physical review. B, Condensed matter, 53(6), 1996, pp. 3119-3123
Citations number
26
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics, Condensed Matter
ISSN journal
0163-1829
Volume
53
Issue
6
Year of publication
1996
Pages
3119 - 3123
Database
ISI
SICI code
0163-1829(1996)53:6<3119:EOGP3E>2.0.ZU;2-#
Abstract
Pressure derivatives of second-order elastic constants of amorphous As have been derived through the use of Schofield's equations and Bhatia -Singh's (BS) parameters. By using these equations the longitudinal an d transverse Gruneisen parameters, which are related to third-order el astic constants (TOEC), have been calculated. A method has been descri bed to evaluate the third-order elastic constants. Shiren's nonlinear parameter has been used to calculate the third-order elastic constant C-155 which is found robe in satisfactory agreement with experiment. N ath-Smith-DeLaunay's equation has been used to compute the position of the absorption band and this is compared with that obtained from BS p arameters. There is good agreement between the two values. The gamma(g )(el) calculated from Nath-Smith-DeLaunay's equation gives good result in agreement with that calculated from gamma(g)(L) and gamma(g)(T), w hich are obtained from Schofield's and BS equations. Phonon frequencie s have been evaluated through the BS method. It is found that in the c ase of omega(L)(k) the collective nature of excitons persists up to la rge wave vector k.