PREPARATION, INFRARED-SPECTRA AND STRUCTURE OF GLASSES IN THE SYSTEM CUCL-CU2O-(P2O5 + MOO3)

Glasses in the system 18.0CuCl-36.5Cu2O-45.5(P2O5+MoO3) with the molar ratio n(Cu2O)/n(P2O5+MoO3)<1 and the MoO3/(P2O5+MoO3) ratio ranging from 0 to 0.9 were prepared. The structure was studied by infrared spectroscopy and Raman spectroscopy. The glasses in the system under study can be classified as glasses which contain one type of cation and various types of polymeric or discrete anions. The presence, in small concentrations, of structural units with networks such as MoO2(PO)2 and (MoO2)2P2O7, is assumed. A phosphate glass without MoO3 is assumed to be made up of a chains of (PO3-)n and by corner-shared chains of (PO3-). in a two- or three-dimensional network. In glasses in which the ratio of MoO3/(P2O5+MoO3) increases, a gradual degradation of the network structural units and (PO3-)n chains and increasing content of a variety of low-condensed or monomeric phosphate and molybdate anions were observed. For glasses with a MoO3/(P2O5+MoO3) ratio <0.8, no new absorption bands belonging to discrete molybdate units were observed in infrared spectra. The spectra of these glasses are explicable mainly in terms of various vibrations of (PO3)n, P3O10, P2O7 and PO4 groupings. The presence of assumed structural units with P-O-Mo units has not been confirmed, unambiguously, in the infrared spectra. New bands which can be attributed to some discrete molybdate structural units were observed in glasses with the largest MoO3/(P2O5+MoO3) ratio.