Structural, magnetization and susceptibility studies on cobalt-ferri-aluminates synthesized by wet-chemical method

Spinel ferrites having the general formula CoAlxFe2-xO4 (x = 0.0-1.0) were prepared using the wet-chemical method. The samples were sintered at 200 de grees C, 500 degrees C and 800 degrees C temperature and were studied by me ans of X-ray diffraction, magnetization and low-field AC susceptibility mea surements. The observed features for the wet samples, such as the intense p eak in chi(AC)-T curve, the co-existence of paramagnetic doublet and magnet ic sextets in Mossbauer spectra and lower saturation magnetization values c onfirm fine particle ferrite behaviour. The variation of saturation magneti zation with Al3(+) substitution is explained on the basis of the Neel's col linear spin model. The cation distribution is estimated from the X-ray inte nsity calculations and magnetization measurements. (C) 2000 Elsevier Scienc e B.V. All rights reserved.