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The magnetic and electric properties of the vanadate PrVO3 with the GdFeO3 -type orthorhombic structure are reported. The temperature-dependent magnetization displays an obvious irreversibility under zero-field cooling (ZFC) and field cooling (FC), and two magnetic phase-transition temperatures 20 K and 90 K, which may correspond to the spin reorientation and the magnetic ordering, respectively. A canted antiferromagnetic configuration is derived from the low spontaneous magnetization at 5 K. In the sintered bulk, a high coercivity 2.4 T is due to the pinning of the domain wall. The resistance measurement shows that the compound is an insulator at low temperatures.

We report the effect of Fe doping on magnetic properties and magnetoresistance (MR) in the layered perovskite La1.2Sr1.8Mn2O7. Fe doping results in the weakening of ferromagnetic (FM) ordering, and the occurrence of a low-temperature spin-glass state in La1.2Sr1.8Mn2−xFexO7. Resistivity increases sharply with increasing Fe concentration. The metal–insulator transition disappears at a very low doping level (x=0.01), but the low-temperature MR effect is enhanced. These effects result from the replacement of Mn3+ by the doped Fe ions, which interrupts the path of double–exchange interaction and destroys the FM metallic state. Due to the anisotropic interaction in the layered perovskite, the magnetic properties and MR effect are more sensitive to Fe doping than those in ABO3-type perovskites.