THE CRITICAL-BEHAVIOR OF THE RAMAN INTENSITIES OF THE LATTICE MODES IN AMMONIUM HALIDES

Date

1993-03-01

Author

Yurtseven, Hasan Hamit

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Our observed Raman intensities for the lattice modes of TA(M)(93 cm-1) and TO(M)(144cm-1) of NH4Cl were used to extract the critical exponents for the order parameter in this crystal system. Our exponent values are 0.15+/-0.02 (1st order, T(c)=241 K, P=0), 0.24+/-0.04 (tricritical, T(c)=255 K, P=1.5 kbar) and 0.33+/-0.10 (2nd order, T(c)=268 K, P=3 kbar), which agree with the model predictions.

URI

https://hdl.handle.net/11511/57530

Journal

JOURNAL OF MOLECULAR STRUCTURE

DOI

https://doi.org/10.1016/0022-2860(93)80343-t

Collections

Department of Physics, Article

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Citation Formats

H. H. Yurtseven, “THE CRITICAL-BEHAVIOR OF THE RAMAN INTENSITIES OF THE LATTICE MODES IN AMMONIUM HALIDES,” JOURNAL OF MOLECULAR STRUCTURE, pp. 175–178, 1993, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/57530.