Dynamics of Deuteron Glasses as Probed by 2 D Exchange NMR

Abstract

Abstract The deuteron intra-bond dynamics o f the deuteron glass phase in Rb0. 68(ND4)0.32D2AsO4 has been studied by 2 D exchange NMR which extends the NMR observation window from the kHz region into the milli-Hertz region. The results show that the O -D···O deuterons are indeed the basic reversible two-position dipoles in the structure and that deuteron intra-bond exchange -and thus dipole reversal transition -occurs deeply in the glass phase well below Tg where 1 D NMR techniques observe only frozen static glassy disorder.