Structural, magnetic and electrical study of CoMnAlO4

Abstract

A spinel CoMnAlO4 has been synthesised by the oxide method. It has a tetragonal structure with A=8.10 A and C=8.22 A. A break is found in the plot of log ρ against 1/T at 573°K when activation energy changes from 0.62 eV to 0·52 eV. The electrical properties show that it can be regarded as a properly substituted CoMn2O4 by Al+3 ions. It is paramagnetic with CM = 4.72 and θ{symbol}a = -298°K. These results show the ionic configuration of the compound as Co+2 [Mn+3 Al+3]O4. © 1982 Indian Academy of Sciences.