RAMAN FREQUENCIES CALCULATED FROM THE VOLUME DATA AS A FUNCTION OF TEMPERATURE AT HIGH PRESSURES FOR THE DISORDERED PHASE II OF NH4I

YURTSEVEN H. H., Kavruk D.

INTERNATIONAL JOURNAL OF MODERN PHYSICS B, cilt.25, sa.4, ss.511-519, 2011 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 25 Sayı: 4
  • Basım Tarihi: 2011
  • Doi Numarası: 10.1142/s0217979211058146
  • Dergi Adı: INTERNATIONAL JOURNAL OF MODERN PHYSICS B
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.511-519
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

In this study, we calculate the Raman frequencies as a function of temperature for the fixed pressures of 706, 1080 and 6355 bars using the volume data for phase 11 of ammonium iodide. The Raman frequencies calculated here are for the translational optic nu(5) TOM (125 cm(-1)) lattice mode that is located at the zone boundary (M point) of the Brillouin zone of phase II for NH4I. For this calculation the volume data obtained at zero pressure, is used through the mode Gruneisen parameter for the disordered phase II (13 phase) which has the CsCI structure of NH4I.