Phase Transformation in the Eu1-xCaxMnO3 Perovskites

Magnetization and crystal structure of Eu1-~Ca,Mn0; (OFx<l) perovskite have been studied. I t is shown that these compou~ids call be divided into four concentration regions in which different magnetic phases coexlst. The antiferromagnetic phases are associated with the regular arrangement of Mn3+ and Mn4+ ions in ratios 1:0, I:]. 1:3 and 0:I respectively. The ferromagnetic phases are attributed to the charge disordered states and arise in O<xs0.4 and 0.8Fx_<1 concentration regions. The samples x=0.8 and 0.85 show metamagnetic behavior which might result from destruction of the charge ordered (13) state.