Pippard relations applied to the lambda-phase transition in NH4Br

Date

2008-11-01

Author

Yurtseven, Hasan Hamit
Sen, S.

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We establish here a linear variation of the specific heat C-p with the frequency shifts (l/v)(partial derivative v/partial derivative T)(p) close to the X-phase transition in NH4Br (T-lambda=234 K). This linear relationship is based on our spectroscopically modified Pippard relations. For this verification of our relations, we use our observed Raman frequencies of the lattice mode of v(7) (56 cm(-1)) and the internal mode of v(2) (1684 cm(-1)) in the NH4Br crystalline system. Our study given here indicates that the thermodynamic data can be obtained from the measured frequencies.

Subject Keywords

Pippard relations, Lambda-transition, NH4Br

URI

https://hdl.handle.net/11511/32751

Journal

SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY

DOI

https://doi.org/10.1016/j.saa.2007.10.053

Collections

Department of Physics, Article

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Citation Formats

H. H. Yurtseven and S. Sen, “Pippard relations applied to the lambda-phase transition in NH4Br,” SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY, pp. 105–109, 2008, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/32751.