AB-INITIO CALCULATIONS OF STRUCTURES, AND RAMAN AND INFRARED-SPECTRA OF VITREOUS B2O3

The structures, and Raman and infrared spectra of vitreous B2O3 have b een investigated by means of ab initio calculations. The calculated fr equencies, structural parameters, and glass transition temperature T-g are in good agreement with experimental data. Some vibrational modes corresponding to some characteristic frequencies are given. The struct ural changes of vitreous B2O3 near the glass transition temperature ar e discussed. By comparing the data obtained from x-ray diffraction and molecular dynamics simulations with the results of ab initio calculat ion, it is concluded that the structures of vitreous B2O3 consist of a random network of planar (BO3) triangles and six-membered (boroxol B3 O6) rings.