title: Evidence for the weak steric hindrance scenario in the supercooled-state reorientational dynamics.
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 nonergodicity parameter. These results are in agreement with the theoretical predictions by the mode-coupling theory for the glass transition.
authors.affiliation: Institute for Molecular Science, Okazaki 444-8585, Japan.
authors.forename: Song-Ho
authors.initials: SH
authors.lastname: Chong
authors.forename: Angel J
authors.initials: AJ
authors.lastname: Moreno
authors.forename: Francesco
authors.initials: F
authors.lastname: Sciortino
authors.forename: Walter
authors.initials: W
authors.lastname: Kob