Electrical and magnetic features in the perovskite-type system Y(Co, Mn)O3

Electrical and magnetic properties of the perovskite-type solid solution YCoxMn1-xO3 (X = 0.20-0.60) have been studied at different temperatures and magnetic fields. Electrical conductivity measurements show a semi-conducting behaviour throughout the solid solution. The room-temperature conductivity increases with the Co content up to 33 at.%, and then decreases. The effective moment in the paramagnetic state shows a non-monotonic decrease, when the Co content increases. In the ordered state, the behaviour at low or null magnetic fields corresponds to a spin-glass or antiferromagnetic system, with a transition temperature, which raises with the Co content (up to 50 at.% Co), and then decreases. At high fields, all the solid solutions show a ferromagnetic behaviour, although there is a marked difference in their ferromagnetic cycles, at a threshold value of 33 at.% Co. (C) 2002 Published by Elsevier Science Ltd.