Dynamics of Deuteron Glasses as Probed by 2 D Exchange NMR *
نویسنده
چکیده
The deuteron intra-bond dynamics of the deuteron glass phase in Rb0 68(N D 4)0 32D 2A s 0 4 has been studied by 2 D exchange NM R which extends the NM R 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 NM R techniques observe only frozen static glassy disorder.
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