Relation between the alpha-relaxation and the Johari-Goldstein Beta-relaxation of a component in miscible blends of two glass-formers

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It is well known that the α-relaxation of each component in a miscible mixtures of two glass-formers has its own dynamics, which change with the composition of the blend. Lesser known are the corresponding change of the Johari-Goldstein (JG) β-relaxation and its relation to the α-relaxation. Previously, in neat glass-formers, the relaxation time of JG β-relaxation was identified with the independent relaxation time τ0 of the coupling model. The correspondence between τ0 and was supported by analysis of experimental data of many glass-formers. In this work, this correspondence between τ0 and of a component in binary mixtures and the relation between τ0 and ταof the coupling model are used to generate predictions of the simultaneous changes of ταand τ of the component on varying the composition of the mixture. The predictions are in accord with the experimental data of the component 2-picoline in mixtures with either tri-styrene or ortho-terphenyl by T. Blochowicz and E.A. Rossler, Phys.Rev.Lett. in press(2004).