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Is there something of the MCT in orientationally disordered crystals ?

F. Affouard·M. Descamps
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Abstract

Molecular Dynamics simulations have been performed on the orientationally disordered crystal chloroadamantane: a model system where dynamics are almost completely controlled by rotations. A critical temperature T_c = 225 K as predicted by the Mode Coupling Theory can be clearly determined both in the alpha and beta dynamical regimes. This investigation also shows the existence of a second remarkable dynamical crossover at the temperature T_x > T_c consistent with a previous NMR and MD study [1]. This allows us to confirm clearly the existence of a 'landscape-influenced' regime occurring in the temperature range [T_c-T_x] as recently proposed [2,3].

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F. Affouard, M. Descamps. 2000-12-20. Is there something of the MCT in orientationally disordered crystals ?. https://doi.org/10.1103/physrevlett.87.035501

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