Structural studies of Fe2O3-Bi2O3-CdO glass system

xFe(2)O(3)center dot(100 - x)[Bi2O3 center dot CdO] system with 0 <= x >= 50 mol% was prepared and investigated by X-ray diffraction, density, FT-IR and Raman spectroscopies. The XRD patterns confirm the formation of a vitreous structure for x < 35 mol% Fe2O3. The evolution of density and molar volume with the addition and increasing of iron content indicates structural changes in the structure of Bi2O3 center dot CdO glass matrix. The FT-IR spectrum of the glass matrix reveals a structure realized from BiO3 pyramidal and BiO6 octahedral units. With the addition of iron the structure proposed by the glass matrix is changing by the appearance of FeO4 units. Also the existence of FeO6 units cannot be excluded. The Raman spectra suggest a structure build from BiO6 octahedral units. By Raman scattering the presence of structural units characteristic to Fe2O3 was not directly observed but the evolution of the spectra is dependent of the iron content. (c) 2007 Elsevier Ltd. All rights reserved.