Structure and magnetic order in the series BixRE1-xFe0.5Mn0.5O3 (RE=La,Nd)

The influence of Bi3+ on the structural and magnetic properties of the rare-earth-containing perovskites REFe0.5Mn0.5O3 (RE=La,Nd) was studied, and the limit of bismuth substitution was determined to be x <= 0.5 in BixRE1-xFe0.5Mn0.5O3+delta (RE=La,Nd) at ambient pressure. Crystal structures in both La and Nd series were determined to be GdFeO3-type Pnma with the exception of the Bi0.3La0.7Fe0.5Mn0.5O3 sample, which is monoclinic I2/a in the a(-)b(-)b(-) tilt scheme. The samples undergo a transition to G-type antiferromagnetic order along with a weak ferromagnetic component, mixed with cluster-glass type behavior. The substitution of bismuth into the lattice results in a drop in T-N relative to the lanthanide end-members. Long range ordering temperatures T-N in the range 240-255 K were observed, with a significantly lower ordered magnetic moment in the case of lanthanum (M similar to 1.7-1.9 mu(B)) than in the case of neodymium (M similar to 2.1 mu(B)). Published by Elsevier Inc.