CRITICAL-VALUES FOR SPECIFIC-HEAT FROM RAMAN DATA

Date

1991-07-01

Author

SHERMAN, WF
Yurtseven, Hasan Hamit

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The use of Raman frequency shifts of non-soft modes to provide detailed predictions of the critical behaviour of specific heat up to within a fraction of a degree of a second order (or weakly first order) phase transition is illustrated. As an example, the lambda-transition of ammonium chloride under ambient pressure has been studied, and values of critical exponents of a- almost-equal-to 0.76 and a+ almost-equal-to 0.82 have been derived for C(p) from the Raman data. This approach is believed to be valid for a wide range of systems showing second-order or weakly first-order phase transitions and it is possible to use it for relatively inaccessible samples such as those within high pressure enclosures.

Subject Keywords

Order-Disorder Transition, Thermal Expansion, NH4 CL

URI

https://hdl.handle.net/11511/56547

Journal

JOURNAL OF MOLECULAR STRUCTURE

DOI

https://doi.org/10.1016/0022-2860(91)87063-n

Collections

Department of Physics, Article

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Citation Formats

W. SHERMAN and H. H. Yurtseven, “CRITICAL-VALUES FOR SPECIFIC-HEAT FROM RAMAN DATA,” JOURNAL OF MOLECULAR STRUCTURE, pp. 61–71, 1991, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/56547.