Abstract
The experimentally observed characteristic features of the α -relaxation process in glass-forming liquids are the non-Arrhenius behavior of the structural relaxation times and the non-Debye character of the macroscopic relaxation function. The Avramov model in which relaxation is considered as an energy activation process of surmounting random barriers in liquid energy landscape was successfully applied to describe the temperature and pressure dependences of the macroscopic relaxation times or viscosity. In this paper, we consider the dielectric spectrum associated with Avramov model. The asymmetrical broadening of the loss spectra was found to be related directly to dispersion of the energy barrier distribution. However, it turns out that temperature dependence of the spectrum broadening as predicted by the Avromov model is at odds to experimental observation in glass-forming liquids.
Original language | English |
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Article number | 094503 |
Journal | Journal of Chemical Physics |
Volume | 127 |
Issue number | 9 |
DOIs | |
State | Published - 2007 |
Bibliographical note
Funding Information:One of the authors (M.P.) wishes to thank the Lady Trust Fellowship for the financial support during the stay in the Department of Applied Physics in the Hebrew University of Jerusalem. He also acknowledges the support of the Polish State Committee for Scientific Research (Project No. 1PO3B 075 28).