title: A neutron scattering and nuclear magnetic resonance study of the structure of GeO2-P2O5 glasses.
abstract: Germanophosphate (GeO2-P2O5) glasses were studied with neutron diffraction, phosphorus, and oxygen nuclear magnetic resonance, calorimetry, viscosity measurements, and first-principles calculations. These data sets were combined to propose a structural model of GeO2-P2O5 glasses, which includes tetrahedrally coordinated phosphorus, formation of octahedrally coordinated germanium as P2O5 content increases, an absence of trigonally coordinated oxygen, and hence an absence of rutile-like GeO2 domains. The structural model was then used to propose explanations for both the observed composition dependence of the glass transition temperature and the fragility of the GeO2-P2O5 liquids.
authors.affiliation: Department of Chemistry and Institute for Research in Materials, Dalhousie University, Halifax, NS, Canada. jzwanzig@dal.ca
authors.forename: J W
authors.initials: JW
authors.lastname: Zwanziger
authors.forename: J L
authors.initials: JL
authors.lastname: Shaw
authors.forename: U
authors.initials: U
authors.lastname: Werner-Zwanziger
authors.forename: B G
authors.initials: BG
authors.lastname: Aitken