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Boson peak, nanostructure and relaxation of glasses

1998; Elsevier BV; Volume: 235-237; Linguagem: Inglês

10.1016/s0022-3093(98)00505-5

1873-4812

E. Duval, A. Mermet, Н. В. Суровцев, A.J. Dianoux,

Theoretical and Computational Physics

In previous papers the low-energy vibrational density of states (boson peak) observed in poly(methyl methacrylate) glass by inelastic neutron scattering is interpreted by the existence of more cohesive nanodomains separated by softer interfacial zones. The log-normal size distribution of nanodomains, that fits the experiment, is justified by the process leading to glass-transition. The fast relaxation in the glass observed by the quasielastic light and neutron scatterings, and the slow one revealed by the dynamic hole volume as deduced from positron annihilation lifetime spectroscopy, are closely related. A model for the interdependence of both relaxations is proposed. The consequences of the relaxational dynamics on viscosity and glass transition are discussed.