IR AND NMR STRUCTURAL STUDIES ON LEAD VANADATE GLASSES

The structure of lead vanadate glasses, xPbO . (100 - x)V2O5, (x = 55, 50, 40, 30) has been investigated by means of infrared and V-51 static and magic angle spinning nuclear magnetic resonance (MAS-NMR) and Pb-207 MAS-NMR spectroscopies. The V-51 NMR spectral parameters of various constituent vanadate groups in lead vanadate glasses were determined by spectrum simulation on the basis of our previous results on alkaline earth vanadate glasses. The structure of 55PbO . 45V(2)O(5) glass mainly consists of VO4 tetrahedra, which are composed of V2O74- and (VO3)(n) single chains. The structure of xPbO . (100 - x)V2O5 glasses (x = 30, 40, 50) consists of both VO4 tetrahedra and VO5 trigonal bipyramids. These VOn polyhedra (n = 4, 5) compose at least four types of vanadate group, i.e., V2O74-, (VO3)(n) single chains, branched VO4 group and (V2O8)(n) zigzag chains depending on the PbO content.