Low Frequency Raman Spectra of v-B2O3 as a Function of Temperature and Pressure.
Abstract
Raman studies of vitreous B2O3 have been conducted between 8 and 700K, and as a function of hydrostatic pressure (about 8 kbar) at room temperature. The low temperature Raman spectra exhibit two broad bands at 50/cm and 137/cm. From the temperature dependence of the 50/cm band, it has been concluded that the vibrational density of states in the low frequency region (30<w<300/cm) is better described when the Raman coupling coefficient C sub b varies as w. A shift in frequency of the Raman spectra as a function of temperature is attributed to a structural change near the glass transition. Near the glass transition temperature, the boroxol rings break up thereby leading to a more open structure. Above the melting point, i.e. when the viscosity is low, a regrouping of atoms occurs which results in a low density random network structure of BO3 triangles.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 08, 1983
- Accession Number
- ADA132699
Entities
People
- George E. Walrafen
- Soumyendu Guha
Organizations
- Howard University