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

Date

2017-01-15

Author

Yurtseven, Hasan Hamit

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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.

Subject Keywords

Damping constant, Raman frequency, Relaxation time, Soft modes, Tetragonal-cubic transition, SrZrO3

URI

https://hdl.handle.net/11511/40271

Journal

JOURNAL OF MOLECULAR STRUCTURE

DOI

https://doi.org/10.1016/j.molstruc.2016.08.050

Collections

Department of Physics, Article

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Citation Formats

H. H. Yurtseven, “Temperature dependence of the damping constant and the relaxation time close to the tetragonal-cubic phase transition in SrZrO3,” JOURNAL OF MOLECULAR STRUCTURE, pp. 51–56, 2017, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/40271.