Calculation of the Brillouin frequencies close to phase transitions in NaNO2

Date

2002-01-01

Author

Yurtseven, Hasan Hamit

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We calculate here the Brillouin frequencies of the L-mode [010], [001] and [100] of NaNO2 for the phase transitions from the paraelectric phase to the sinusoidal anti-ferroelectric phase near the Neel temperature (T-N = 437.7 K) and to the ferroelectric phase near the critical temperature (T-c = 436.3 K) in this crystalline system. For calculating the frequencies, we use the thermal expansivity data for the phase regions considered, under the assumption that the mode Gruneisen parameter determined for each mode remains constant across the phase transitions. Our calculated frequencies agree well with the observed frequencies for the modes studied in NaNO2.

Subject Keywords

Brillouin frequencies, Phase transitions, NaNO2

URI

https://hdl.handle.net/11511/57483

Journal

SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY

DOI

https://doi.org/10.1016/s1386-1425(01)00505-4

Collections

Department of Physics, Article

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Citation Formats

H. H. Yurtseven, “Calculation of the Brillouin frequencies close to phase transitions in NaNO2,” SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY, pp. 55–65, 2002, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/57483.