Direct observation of molecular cooperativity near the glass transition

E. Vidal Russell; N. E. Israeloff

doi:10.1038/35047037

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arXiv · cond-mat/0012245

Direct observation of molecular cooperativity near the glass transition

E. Vidal Russell·N. E. Israeloff

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Abstract

We describe direct observations of molecular cooperativity near the glass transition in poly-vinyl-acetate (PVAc), through nanometer-scale probing of dielectric fluctuations. Molecular clusters switched spontaneously between two to four distinct configurations, producing complex random-telegraph-signals (RTS). Analysis of the RTS and their power spectra shows that individual clusters exhibit both transient dynamical heterogeneity and non-exponential kinetics.

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E. Vidal Russell, N. E. Israeloff. 2000-12-13. Direct observation of molecular cooperativity near the glass transition. https://doi.org/10.1038/35047037

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