Accession Number : AD0700116

Title :   EFFECT OF UNIAXIAL STRESS ON THE VIBRATIONAL MODES IN QUARTZ,

Corporate Author : COLORADO STATE UNIV FORT COLLINS DEPT OF PHYSICS

Personal Author(s) : Harker,Yale D. ; She,Chiao Y. ; Edwards,David F.

Report Date : OCT 1969

Pagination or Media Count : 181

Abstract : The detailed lineshapes of five Raman lines were measured for an alpha-quartz sample as a function of applied uniaxial stress. It was observed that the vibrational frequencies and line intensities increased, and the linewidths initially decreased with the application of compressive stress. As an example, the frequency of the 207 reciprocal cm A1-mode increased 3.85 reciprocal cm, its intensity increased 30% and its linewidth decreased 3.5 reciprocal cm for an applied stress of 3 x 10 to the 9th power dynes/sq cm. The stress induced shifts for the three A1-lines were observed to have a non-monotonic frequency dependence. The valence-force model used for calculating normal mode frequencies was modified by including the effects of an anharmonic potential and applied stress. This modified model was used to predict the stress induced changes in frequency for the four A1-modes in quartz. The predicted shifts are of the same order of magnitude as those measured and possess the observed nonmonotonic frequency dependence. The results of the calculations and measurements demonstrate the differing characteristics of the A1-modes lie in the motion of the oxygen atoms. (Author)

Descriptors :   (*QUARTZ, *RAMAN SPECTROSCOPY), (*LASERS, DAMAGE), (*STRAIN(MECHANICS), DETECTION), VIBRATION, STRESSES, CRYSTAL LATTICES, LINE SPECTRA, SCATTERING, LIGHT TRANSMISSION, COMPUTER PROGRAMS, OPTICAL MATERIALS, THESES, (U)THESES

Subject Categories : Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE