Some examples of recent advances in experiment and theory that have impact on solution of the glass transition problem are briefly discussed. The fundamental importance of a special class of secondary relaxations called the Johari-Goldstein beta-relaxations becomes clear from the recent advances. The main part of the paper addresses a recent research problem, which is the purported anomalous temperature dependence of the relaxation time of another secondary (gamma) relaxation found by fitting dielectric relaxation data in several glass-formers. We show the anomalous T-dependence of this faster gamma-relaxation is caused by the influence exerted by the slower Johari-Goldstein beta-relaxation in the vicinity. (C) 2008 Elsevier B.V. All rights reserved.
Recent advances in fundamental understanding of glass transition
CAPACCIOLI, SIMONE
2008-01-01
Abstract
Some examples of recent advances in experiment and theory that have impact on solution of the glass transition problem are briefly discussed. The fundamental importance of a special class of secondary relaxations called the Johari-Goldstein beta-relaxations becomes clear from the recent advances. The main part of the paper addresses a recent research problem, which is the purported anomalous temperature dependence of the relaxation time of another secondary (gamma) relaxation found by fitting dielectric relaxation data in several glass-formers. We show the anomalous T-dependence of this faster gamma-relaxation is caused by the influence exerted by the slower Johari-Goldstein beta-relaxation in the vicinity. (C) 2008 Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.