Magnetic properties of Zn-substituted Li-Cu ferrites

The magnetic properties of Zn-substituted Li-Cu ferrites having the general formula LixCu0.4Zn0.6-2xFe2+xO4 (where, x = 0.0, 0.05, 0.1, 0.15, 0.2, 0.35 and 0.3) are investigated as a function of Zn content. The X-ray analysis confirms the formation of single-phase of the samples. The lattice parameter increased linearly with Zn content, which is attributed to ionic size differences of the cations involved. The bond lengths R-A and R-B are found to increase with increase in Zn content. The increase of R-A and RB is attributed to the increase in lattice parameter. The magnetic moment increases with increase in zinc content up to 0.3 and then it decreases with further addition of Zn. The decrease in magnetic moment beyond Zn = 0.3 is due to the presence of a triangular spin arrangement on B-site; the three sublattice model suggested by Yafet and Kittle. The initial permeability (mu (i)) has been measured, and it is found that it decreases with increase in Zn content. The Curie temperatures also show a decreasing trend. (C) 2001 Elsevier Science B.V. All rights reserved.