Soft-mode raman and infrared spectroscopy in As.2Sb.8SI crystals
- 1 January 1980
- journal article
- research article
- Published by Taylor & Francis in Ferroelectrics
- Vol. 25 (1) , 605-608
- https://doi.org/10.1080/00150198008207081
Abstract
The temperature dependence of the polar and not polar optical lattice vibrations of the ferroelectric As.2Sb.8SI crystal is investigated using both polarised infrared reflective and Raman techniques. We observed for the first time all the ten B2u +B3u modes and all the 16 B1 +B2 modes predicted from group theory for the full space group symmetry D16 2n and C9 2v with four moleculars per unit cell in the paraelectric and ferroelectric phase respectively common for all known AvBviCvii compounds. Coupled soft mode behavior is observed as frequency anticrossing and level repulsion in the Raman spectra of the ferroelectric phase, but only as line shape anomalies in the infrared spectraKeywords
This publication has 9 references indexed in Scilit:
- Atomic substitution and ferroelectric phase transition inPhysical Review B, 1978
- Optical phonons and phase transitions of SbSBr-SbSi mixed crystalsFerroelectrics, 1976
- Temperature dependence of transverse- and longitudinal-optic modes in Ti(rutile)Physical Review B, 1974
- Soft-mode spectroscopy: Experimental studies of structural phase transitionsReviews of Modern Physics, 1974
- Phonons and Ferroelectric Phase Transitions in SbSBr and SbSI and Their Solid SolutionsPhysical Review B, 1973
- Long-Wavelength Optical Phonons and Phase Transitions in SbSIPhysical Review B, 1971
- Soft phonon mode and mode coupling in SbSISolid State Communications, 1970
- Domain Structure Observed on Antiferroelectric PbZrO3 CeramicsPhysica Status Solidi (b), 1969
- Coupled-Optical-Phonon-Mode Theory of the Infrared Dispersion in BaTi, SrTi, and KTaPhysical Review B, 1964