Variation of the Raman frequency of a soft mode with the pressure (20 oC) for the phase transitions in NH4F

Date

2016-04-21

Author

Yurtseven, Hasan Hamit

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The Raman frequency of a soft mode (238 cm⁻¹) is analyzed as a function of pressure at 20 oC for NH4F using the experimental data from the literature. This analysis is performed for the pressure dependence of the Raman frequency shifts (1 / n )( ¶ n / ¶ P)T of the soft mode close to the I - III, III - V and V – VI transitions in NH4F. The frequency shifts increase as the pressure increases toward the phase transitions at T = 20 oC (293 K) in this ammonium structure. From the frequency shifts of the soft mode studied, the pressure dependence of the isothermal compressibility is predicted through the mode Grüneisen parameter. Our calculated isothermal compressibility can be compared with the experimental measurements.

Subject Keywords

Raman frequency, Soft mode, Phase transitions, NH4F

URI

https://hdl.handle.net/11511/84264

DOI

https://doi.org/10.18038/aubtda.267109

Conference Name

Adım Fizik Günleri , (21 - 23 Nisan 2016)

Collections

Department of Physics, Conference / Seminar

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Citation Formats

H. H. Yurtseven, “Variation of the Raman frequency of a soft mode with the pressure (20 oC) for the phase transitions in NH4F,” presented at the Adım Fizik Günleri , (21 - 23 Nisan 2016), Türkiye, 2016, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/84264.