Temperature dependence of the damping constant and the relaxation time close to the tetragonal-cubic phase transition in SrZrO3

YURTSEVEN H. H., Kiraci A.

JOURNAL OF MOLECULAR STRUCTURE, vol.1128, pp.51-56, 2017 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 1128
  • Publication Date: 2017
  • Doi Number: 10.1016/j.molstruc.2016.08.050
  • Journal Name: JOURNAL OF MOLECULAR STRUCTURE
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.51-56
  • Keywords: Damping constant, Raman frequency, Relaxation time, Soft modes, Tetragonal-cubic transition, SrZrO3, ACOUSTIC MODE, SCATTERING, CRYSTALS
  • Middle East Technical University Affiliated: Yes

Abstract

The damping constant Gamma(sp) due to the pseudospin-phonon coupling is calculated as a function of temperature using the pseudospin-phonon coupled model and the energy fluctuation model close to the tetragonal-cubic transition (T-C = 1443 K) in SrZrO3. Using the observed Raman frequencies and the linewidth (FWHM) of the soft modes (E-g and A(1g)) from the literature, predictions of both models studied, are examined for the tetragonal-cubic transition in this crystalline system. Values of the activation energy U are extracted and also the inverse relaxation time is predicted as a function of temperature close to the phase transition studied in SrZrO3.