OPTICAL VIBRATION SPECTRA OF SOLIDS.
Abstract
The infrared reflection and/or transmission spectra of CdS, ZnS, ZnO, BN, NiO, CoO, and their mixed crystals, MnO, Al2O3, Mg(OH)2 and Cu2S are reported at one or more temperatures. The Raman spectrum of ZnO is also reported. The experimental investigations also included the study of crystal field spectra of Ni(2+), Co(2+) and Mn(2+) in their respective monoxides. The infrared and the ultraviolet absorption by U-centers in alkali halides was studied and interpreted in terms of localized virational modes of the impurity centers. Theoretical investigations include discussions on: (i) The trends in the characteristic phonon frequencies of the II-VI compounds, (ii) the assignment of the multiphonon infrared absorption in GaAs using the space group selection rules, (iii) the validity of the LyddaneSachs-Teller relationship at long wavelengths, (iv) the combination of the lattice modes with the internal modes in a crystal containing polyatomic groups, and (v) the Gruneisen parameter for long wavelength optical modes in ionic crystals. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 03, 1965
- Accession Number
- AD0626595
Entities
People
- Shashanka S. Mitra
Organizations
- IIT Research Institute