کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1238893 968965 2005 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Infrared reflectance spectra of some optically biaxial crystals: on the origin of isosbestic-like points in the polarized reflectance spectra
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
Infrared reflectance spectra of some optically biaxial crystals: on the origin of isosbestic-like points in the polarized reflectance spectra
چکیده انگلیسی

An investigation of the IR polarized reflectance spectra of the orthorhombic K2SO4, KHSO4 and monoclinic CaSO4·2H2O, K2Ni(SO4)2·6H2O, (NH4)2Ni(SO4)2·6H2O was performed in order to explain the appearance of particular intersection points in their spectra. The analogy in the origin of the appearance of intersection points and the well-known isosbestic points in UV–vis and IR spectra was discussed. The reason for such an appearance was identified in the way that the individual reflectances (for radiation polarized along principal dielectric axes) sum up to give the reflectance under arbitrary polarization. This summation may also produce supplementary bands in the reflectance spectra, not predicted by the group theory. It was shown that relatively large LO–TO splitting is needed for the supplementary band(s) to appear, but also the overlapping region must be taken into account.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy - Volume 61, Issue 9, July 2005, Pages 2057–2063
نویسندگان
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