Quadrupolar glass ordering in solid deuterium

2014 Measurements of the NMR absorption line shapes have been used to establish the phase diagram for orientational ordering of the J = 1 molecules in solid mixtures of paradeuterium (J = 1) and orthodeuterium (J = 0) for para concentrations 42 X 75 % and temperatures 0.035 T 2.5 K. As in solid hydrogen, we observe three phases : a rotationally disordered phase, a long range orientationally ordered phase for concentrations of the J = 1 species greater than a critical concentration Xc ~ 55 % and a hitherto unreported ordered phase in solid deuterium for X Xc. The nature of the ordering in the new phase has been determined by analysing the NMR line shapes. There is a large distribution of local orientational order parameters for X Xc and we interpret the transitions observed for low concentrations as a quadrupolar glass ordering of the orientational degrees of freedom of the J = 1 molecules. LE JOURNAL DE PHYSIQUE LETTRES TOME 40, ler NOVEMBRE 1979,