December 2001
·
9 Reads
·
16 Citations
Physical Review B
We have used a first-principles method based on the density functional theory to investigate the Raman spectrum of a- By calculating vibrational frequencies and associated Raman intensities for a series of cluster models, we arrive at an interpretation of the observed spectrum that directly links spectral features to structural units in the glass. The results indicate that edge-sharing chains containing three tetrahedra are a dominant structural motif in the stoichiometric glass.