Magnetic Properties of Transition Ion Pyrophosphates

Abstract

<p> The magnetic properties of MnP2O7, CuP2O7, Co2P2O7 and Ni2P2O7 were studied. They were investigated using magnetic susceptibility and magnetic resonance techniques. They were all found to become magnetically ordered between 10°K and 30°K. In all the predominant exchange interaction was antiferromagnetic. Ni2P2O7 however did show a resultant moment at low temperatures which was attributed to weak ferrornagnetism. The experimental results were analysed in the molecular field approxmation which accounted for their behaviour except in the case of Cu2P2O7 where the High Temperature Series Expansion method was necessary to explain the temperature dependence of its paramagnetic susceptibility. </p>