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arXiv · 0707.2800

Dielectric spectroscopy in benzophenone: The beta relaxation and its relation to the mode-coupling Cole-Cole peak

L. C. Pardo·P. Lunkenheimer·A. Loidl
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Abstract

We report a thorough characterization of the glassy dynamics of benzophenone by broadband dielectric spectroscopy. We detect a well pronounced beta relaxation peak developing into an excess wing with increasing temperature. A previous analysis of results from Optical-Kerr-effect measurements on this material within the mode coupling theory revealed a high-frequency Cole-Cole peak. We address the question if this phenomenon also may explain the Johari-Goldstein beta relaxation, a so far unexplained spectral feature inherent to glass-forming matter, mainly observed in dielectric spectra. Our results demonstrate that according to the present status of theory, both spectral features seem not to be directly related.

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L. C. Pardo, P. Lunkenheimer, A. Loidl. 2007-10-08. Dielectric spectroscopy in benzophenone: The beta relaxation and its relation to the mode-coupling Cole-Cole peak. https://doi.org/10.1103/physreve.76.030502

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