Vibrational Spectra of Oxygen- and Boron-Isotopically Substituted B2O3 Glasses

摘要

The Raman spectra of 10B, 11B, 16O, 18O, and mixed isotopic compositions of B2O3 (gl) are reported. The 808/cm band assigned to the boroxol ring structure is found to shift upon oxygen isotope substitution, and not to depend on the boron mass. It is replaced by four bands, in the intensity ratio 1:3:3:1, in the case of the 50% 16O-50% 18O-containing material. On the other hand, the frequencies other principal bands depend on the masses of both boron and oxygen. The ca 1260/cm band, in particular, depends on the masses of both, and shifts without broadening upon partial oxygen substitution. The analysis of these data shows that both a local unit, behaving as predicted for the boroxol ring, and a continuous random network of connecting bonds are manifested in the spectra. (Author)