title: Brillouin-scattering study of propylene carbonate: an evaluation of phenomenological and mode coupling analyses.
abstract: Brillouin-scattering spectra of the molecular glass-forming material propylene carbonate (PC) in the temperature range 140 K to 350 K were analyzed using both the phenomenological Cole-Davidson memory function and a hybrid memory function consisting of the Cole-Davidson function plus a power-law term representing the critical decay part of the fast beta relaxation. The spectra were also analyzed using the extended two-correlator schematic mode-coupling theory (MCT) model recently employed by Götze and Voigtmann to analyze depolarized light backscattering, dielectric, and neutron-scattering spectra of PC [Phys. Rev. E 61, 4133 (2000)]. We assess the ability of the phenomenological and MCT fits, each with three free fitting parameters, to simultaneously describe the spectra and give reasonable values for the alpha-relaxation time tau(alpha).
authors.affiliation: Physics Department, City College of the City University of New York, New York, New York 10031, USA.
authors.forename: Alexander
authors.initials: A
authors.lastname: Brodin
authors.forename: Martin
authors.initials: M
authors.lastname: Frank
authors.forename: Sabine
authors.initials: S
authors.lastname: Wiebel
authors.forename: Guoqing
authors.initials: G
authors.lastname: Shen
authors.forename: Joachim
authors.initials: J
authors.lastname: Wuttke
authors.forename: H Z
authors.initials: HZ
authors.lastname: Cummins