Spectroscopic modifications of Pippard relations: Tricritical phase transition in NH4Cl

Date

2006-12-01

Author

Yurtseven, Hasan Hamit

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We study here the Pippard relations modified spectroscopically for the NH4Cl crystal. By relating the specific heat C-P to the frequency shift (1/v)(partial derivative v/partial derivative T)(P) for the disorder-allowed Raman modes of v(7) (93 cm(-1)) and v(5) (144 cm(-1)) in NH4Cl close to the tricritical point (P = 1.6 kbar, T-C = 257 K), we show that the first Pippard relation is valid for this crystalline system.

Subject Keywords

Spectroscopy, Atomic and Molecular Physics, and Optics, Radiation

URI

https://hdl.handle.net/11511/35000

Journal

JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER

DOI

https://doi.org/10.1016/j.jqsrt.2006.02.031

Collections

Department of Physics, Article

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Citation Formats

H. H. Yurtseven, “Spectroscopic modifications of Pippard relations: Tricritical phase transition in NH4Cl,” JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER, pp. 513–518, 2006, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/35000.