MOLECULAR AND STRUCTURAL RELAXATIONS IN A GLASSY CRYSTAL

Glassy crystals are expected to be the genuine rotational analogues of conventional glasses. Cyanoadamantane has the advantage, over other glassy crystals, that it can be grown and quenched in the state of perfect single crystals of its plastic phase. This overview of CNa shows that it allows (i) to obtain a detailed microscopic description of the disorder rendering the analyse of dynamic data more straightforward and (ii) to detect frozen short range order. Emphasis is placed on real-time X-ray experiments which allow to characterize slow sub-T(g) structural relaxations and thermal history effects around T(g).