Frequency shifts of the disorder-induced modes close to the tricritical phase transition in NH4Cl

Date

2003-01-01

Author

Yurtseven, Hasan Hamit

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We have studied the Raman frequencies of the disorder-induced modes of v, (93 cm(-1)) and v(5) (144 cm(-1)) close to the tricritical phase transition in NH4Cl (P 1.6 kbar, T. 257 K). Using our observed Raman data for these phonon modes, we have obtained the value of the exponent a approximate to 0.3 for the frequency shifts, which can describe the critical behaviour of the thermal expansivity a, and also of the specific heat Cp. Our exponent value can be compared with the value of 0.1 predicted by the 3d Ising model.

Subject Keywords

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

URI

https://hdl.handle.net/11511/41694

Journal

HIGH TEMPERATURES-HIGH PRESSURES

DOI

https://doi.org/10.1068/htjr068

Collections

Department of Physics, Article

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Citation Formats

H. H. Yurtseven, “Frequency shifts of the disorder-induced modes close to the tricritical phase transition in NH4Cl,” HIGH TEMPERATURES-HIGH PRESSURES, pp. 471–476, 2003, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/41694.