Critical behavior of the disorder-induced Raman modes close to the lambda-phase transition in NH4Cl

Yurtseven, HASAN; Kayisoglu, D

doi:10.1016/s1386-1425(01)00632-1

Critical behavior of the disorder-induced Raman modes close to the lambda-phase transition in NH4Cl

Atıf İçin Kopyala

Yurtseven H. H., Kayisoglu D.

SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY, cilt.58, sa.8, ss.1823-1830, 2002 (SCI-Expanded)

Yayın Türü: Makale / Tam Makale
Cilt numarası: 58 Sayı: 8
Basım Tarihi: 2002
Doi Numarası: 10.1016/s1386-1425(01)00632-1
Dergi Adı: SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
Sayfa Sayıları: ss.1823-1830
Orta Doğu Teknik Üniversitesi Adresli: Hayır

Özet

This study gives our analysis of the disorder-induced Raman modes of v(7) (93 cm(-1)) and v. (144 cm(-1)) close to the lambda-phase transition (P = 0) in the NH4Cl crystal. We describe the critical behavior of the frequency shifts for those modes by a power-law formula and using our Raman data we obtain the value of 0.1 for the critical exponent which can also describe the critical behavior of the thermal expansivity and the specific heat of NH4Cl Close to its A-phase transition (T-lambda = 242.9 K). (C) 2002 Elsevier Science B.V. All rights reserved.