Magnetic properties of La1-xPrxCrO3

Magnetic properties have been investigated for the perovskite La1-xPrxCrO3 (0 less than or equal to x less than or equal to 1), which is a solid solution series between LaCrO3 (x = 0) and PrCrO3 (x = 1), based on de magnetization and neutron diffraction measurements. The crystal structures were assigned to an orthorhombic perovskite type (space group Pnma) in the whole composition region. Canted-antiferromagnetic order is commonly observed at the Neel temperatures (T-N) of 288-240 K. In low applied magnetic fields (less than or similar to 5000 Oe), the solid solutions with a wide composition range of 0.2 less than or equal to x less than or equal to 0.8 exhibit distinct negative magnetization below the compensation temperatures (T-comp) (less than or similar to 230 K). It is characteristic that the absolute values of such magnetization are much larger (by similar to 250 times in the largest case with the applied field of 100 Oe) than the positive ordered magnetization observed between T-N and T-comp. Neutron diffraction data for La0.5Pr0.5CrO3 showed the existence of G(y)-type (G(z) for Pbnm) antiferromagnetic order of Cr3+ moments with no crystallographic change below TN. Considering the fact that the present behavior is similar to that in GdCrO3, this is plausibly ascribed to the antiparallel coupling of the Pr3+ moments and the canted Cr3+ moments. (C) 2001 Academic Press.