Abstract
In the present investigation the samples with chemical composition Ca(CoTi)0.5(MnZn)x/2Fe11-xO19 with (x = 0 to 0.6) were synthesized using perfect stoichiometric proportions of reacting oxides by standard ceramic technique. It shows hexagonal magnetoplumbite (M) structure having unit cell dimensions ‘a’ and ‘c’ varies between 5–6 Å and 21–23 Å with same space group P63/mmc (No. 194). The temperature dependent electrical conductivity measurements were carried out at 300–650 K. The compounds are ferromagnetic nature upto Curie temperature and above this show paramagnetic nature. The activation energy has been observed more in paramagnetic region than ferromagnetic region. The temperature dependente magnetic susceptibility measurement has been carried out and from this Curie molar constant has been found to decrease with the increase in Mn-Zn concentration with respect to Curie temperature. There is no significant variation in lattice parameter with Mn-Zn concentration.