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Evidence for the weak steric hindrance scenario in the supercooled-state reorientational dynamics

S. -H. Chong·A. J. Moreno·F. Sciortino·W. Kob
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Abstract

We use molecular-dynamics computer simulations to study the translational and reorientational dynamics of a glass-forming liquid of dumbbells. For sufficiently elongated molecules the standard strong steric hindrance scenario for the rotational dynamics is found. However, for small elongations we find a different scenario -- the weak steric hindrance scenario -- caused by a new type of glass transition in which the orientational dynamics of the molecule's axis undergoes a dynamical transition with a continuous increase of the non-ergodicity parameter. These results are in agreement with the theoretical predictions by the mode-coupling theory for the glass transition.

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S. -H. Chong, A. J. Moreno, F. Sciortino, W. Kob. 2005-04-27. Evidence for the weak steric hindrance scenario in the supercooled-state reorientational dynamics. https://doi.org/10.1103/physrevlett.94.215701

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