Direct detection of connectivities in glasses by 2D NMR

Abstract

Abstract 31 P two-dimensional (2D) nuclear magnetic resonance (NMR) is proposed a powerful tool for direct investigation of the connectivities between like or different Q n units in glasses or the medium-range order. The entire experiment was carried out under conditions of fast magic angle sample spinning (MAS). The magnetization transfer was obtained by recoupling of the dipole-dipole interaction despite the fast MAS. The mixing time dependence of the 2D spectra for a binary Na 2 OP 2 O 5 glass suggests an almost regular alternation of Q 2 and Q 3 units for that glass.