2006/02/24 by Matthias Sperl · 1 citation
Chemical Engineering · Materials Science · Physics and Astronomy · #Material Dynamics and Properties #Spectroscopy and Quantum Chemical Studies #Thermodynamic properties of mixtures #cond-mat.soft #cond-mat.stat-mech
paper · pdf · doi:10.1103/physreve.74.011503
published as Phys. Rev. E 74, 011503 (2006) · 15 pages, 9 figures
arxiv created 2006/02/24 · openalex publication_date 2006/07/13 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Within the mode-coupling theory (MCT) for glassy dynamics, the asymptotic low-frequency expansions for the dynamical susceptibilities at critical points are compared to the expansions for the dynamic moduli; this shows that the convergence properties of the two expansions can be quite different. In some parameter regions, the leading-order expansion formula for the modulus describes the solutions of the MCT equations of motion outside the transient regime successfully; at the same time, the leading- and next-to-leading-order expansion formulas for the susceptibility fail. In these cases, one can derive a Cole-Cole law for the susceptibilities; and this law accounts for the dynamics for frequencies below the band of microscopic excitations and above the high-frequency part of the alpha peak. It is shown that this scenario explains the optical-Kerr-effect data measured for salol and benzophenone (BZP). For BZP it is inferred that the depolarized light-scattering spectra exhibit a wing for the alpha peak within the Gigahertz band. This wing results from the crossover of the von Schweidler law part of the alpha peak to the high-frequency part of the Cole-Cole peak; and this crossover can be described quantitatively by the leading-order formulas of MCT for the modulus.