Specific heat calculated from the Raman frequency shifts close to the gimel-phase transition in NH4Br

Date

2003-01-01

Author

Yurtseven, Hasan Hamit

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We calculated the specific heat C-VI close to the lambda-phase transition in NH4Br on the basis of predictions of the Ising model. We have used our observed Raman frequencies of the nu(5) (134 cm(-1)) lattice mode to extract the critical exponent for the specific heat. The C-VI values calculated by us with this exponent value agree with the measured C-P data reported in the literature. This agreement is particularly good above T-lambda. This indicates that the observed behaviour of NH4Br can be satisfactorily explained close to the lambda-phase transition in this crystal.

Subject Keywords

Physical and Theoretical Chemistry, Mechanics of Materials, Condensed Matter Physics

URI

https://hdl.handle.net/11511/44555

Journal

HIGH TEMPERATURES-HIGH PRESSURES

DOI

https://doi.org/10.1068/htjr070

Collections

Department of Physics, Article

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Citation Formats

H. H. Yurtseven, “Specific heat calculated from the Raman frequency shifts close to the gimel-phase transition in NH4Br,” HIGH TEMPERATURES-HIGH PRESSURES, pp. 321–327, 2003, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/44555.