Structural properties of glasses in the series (SrO){sub x}(V{sub 2}O{sub 5}){sub 1-x} (SrO){sub 0.5-y}(B{sub 2}O{sub 3}){sub y}(V{sub 2}O{sub 5}){sub 0.5}, and (SrO){sub 0.2}(B{sub 2}O{sub 3}){sub z}(V{sub 2}O{sub 5}){sub 0.8-z}

In order to further elucidate the local structure of vanadate glasses, x-ray photoelectron spectroscopy (XPS) and magnetization studies are reported on a series of SrO-vanadate and SrO-borovanadate glasses: [(SrO){sub x}(V{sub 2}O{sub 5}){sub 1-x}], [(SrO){sub 0.5-y}(B{sub 2}O{sub 3}){sub y}(V{sub 2}O{sub 5}){sub 0.5}], and [(SrO){sub 0.2}(B{sub 2}O{sub 3}){sub z}(V{sub 2}O{sub 5}){sub 0.8-z}]. From the analysis of the XPS spectra for the Sr 3p, B 1s, V 2p, and O 1s core levels, several distinct concentration regimes are identified in terms of various structural units being present. Metavanadate chainlike structures of SrV{sub 2}O{sub 6} and individual VO{sub 4} units occur in vanadate glasses with low SrO content x{<=}0.2 with VO{sub 5} polyhedra also appearing at higher SrO content. The SrV{sub 2}O{sub 6} and VO{sub n} polyhedra predominate in the low B{sub 2}O{sub 3} containing SrO-borovanadate glasses as the B substitutes into the V sites of the various VO{sub n} polyhedra and only when the B{sub 2}O{sub 3} concentration exceeds the SrO content do BO{sub n} structures appear. This qualitative picture of three distinct structural groupings for the Sr-vanadate and Sr-borovanadate glasses is consistent with the proposed glass structure based on previous IR and extended x-ray absorption fine structure (EXAFS) studies on these typesmore » of vanadate glasses.« less