Premium
Grüneisen Parameter for Long Wavelength Optical Modes in Ionic Crystals
Author(s) -
Mitra S. S.
Publication year - 1965
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.19650090222
Subject(s) - normal mode , mode (computer interface) , ionic bonding , ionic crystal , ion , materials science , center (category theory) , crystal (programming language) , wavelength , transverse plane , volume (thermodynamics) , infrared , frequency spectrum , function (biology) , condensed matter physics , optics , thermodynamics , physics , chemistry , crystallography , quantum mechanics , vibration , engineering , structural engineering , evolutionary biology , biology , computer science , programming language , spectrum analyzer , operating system
The Grüneisen parameter, γ i for a normal mode of a crystal may be determined from the temperature or pressure coefficient of the normal mode frequency if it is assumed that the mode frequency is only a function of volume. γ t for the zone center transverse optical mode frequency of RbI is obtained from its temperature dependent infrared spectrum. Expressions for γ t and γ l for the T.O. and L.O. modes at k ≈ 0 are derived from the Born and Huang theory using the rigid ion approximation.