The Structure of GeS<INF>2</INF>-P<INF>2</INF>S<INF>5</INF> Glasses

Structural models of (GeS<INF>2</INF>)<INF>1</INF><INF>-</INF><INF>x</INF><INF></INF>(P<INF>2</INF>S<INF>5</INF>)<INF>x</INF><INF></INF> glasses were developed and used to explain bulk properties of the glasses, including density, glass transition temperature, and refractive index. The models were developed based on combined data from solid-state NMR measurements of spectra and magnetic dipole distributions, neutron diffraction, and Raman spectroscopy. The fundamental structural groups of these glasses consist of GeS<INF>4/2</INF> tetrahedra, and both S&dbd;PS<INF>3/2</INF> and PS<INF>3/2</INF> phosphorus units, the latter necessitating also the presence of sulfur−sulfur bonding. Furthermore, the phosphorus sites are present in both network sites and molecular clusters.