Analysis of the frequency shifts close to the second order phase transition in NH4Cl

Date

2001-03-01

Author

Yurtseven, Hasan Hamit

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In this study we analyzed observed Raman data for the frequencies of the disorder-induced modes of v(7) (93 cm(-1)) and vs (144 cm(-1)) in the second order phase region of NH4Cl (P = 2.8 kbar). By means of a power-law formula describing the critical behaviour of the frequency shifts 1/v(partial derivativev/partial derivativeT)p for those phonon modes studied, we extract the critical exponent value of a = 0.25, which can also describe the critical behaviour of the specific hear Cp close to the second order phase transition in NH4Cl. Within this content, our spectroscopically modified Pippard relations are introduced here.

Subject Keywords

Phase transitions, Ammonium halides, Disorder-induced modes, NH4Cl, Phase transitions, Raman

URI

https://hdl.handle.net/11511/56812

Journal

SPECTROSCOPY LETTERS

DOI

https://doi.org/10.1081/sl-100002004

Collections

Department of Physics, Article

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Citation Formats

H. H. Yurtseven, “Analysis of the frequency shifts close to the second order phase transition in NH4Cl,” SPECTROSCOPY LETTERS, pp. 147–157, 2001, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/56812.