X-RAY AND BULK MAGNETIC STUDIES ON LI0.5ZNXTIXFE2.5-2XO4

Lattice parameter 'a' in the system Li0.5(ZnTi)(x)Fe2.5-2x0(4) increases monotonically with x, which is attributed to ionic volume differences of the cations involved. The grain size dm increases with the increase of (Zn2+Ti4+) concentration to x = 0.3 while for x > 0.3 the grain size shows a decrease with increase of x. The initial permeability first increases gradually and then rapidly with temperature, mu-i = 0 at T(c) and its value drops sharply near T(c), suggesting single phase ferrite formation. The addition of Ti4+ enhances mu-i values while T(c) values are lowered. The increase of ui with x is due to a decrease of K1. The decrease of T(c) with x is attributed to weakening of A-B interactions due to overall reduction of Fe3+ ions. From 1 KHz onwards mu-i is frequency independent while all the samples show large dispersion on the low frequency side. Variation of n(B) with x reveals that for x < 0.3, n(B) increases with increase of x while for x > 0.3, n(B) decreases with increase of x. Normalised susceptibility studies show that all the samples contain M.D. particles.