Alkali And Alkali-Lead Oxynitride Phosphate Glasses: A Comparative Structural Study By Nmr And Xps

Nitrided phosphate glasses are characterised by tetrahedral units P(0,N)4 in which nitrogen atoms have substituted for both bridging and non-bridging double bonded oxygen atoms. 31P magic angle spinning nuclear magnetic resonance shows that PO4, PO3N and PO2N2 tetrahedra may coexist within the glass network. The relative proportion of these structural units as function of the N/P ratio depends on the composition of the oxide base glass, as illustrated in sodium, lithium-sodium-lead phosphate glasses.