The size of cooperatively rearranging regions at the glass transition
Abstract
For six glass forming substances of very different kinds the volumes of cooperatively rearranging regions (CRR) and the corresponding correlation lengths are calculated using parameters obtained by Moynihan et al. from thermograms and formulas from a fluctuation theory of glass transition. The correlation lengths range from 0.7 nm for a crown glass up to 2.2 nm for a lubricant oil. The CRR contains between 35 and 290 strongly interacting particles. The consequences of such wide correlations are discussed with respect to the relations between the dynamic glass transition, the freezing-in process, and the structure of glasses.
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