Magnetic structure evolution of NdMnO₃derived from neutron diffraction data

Abstract

The orthorhombic NdMnO3perovskite (space group Pnma ) has been studied on the basis of magnetization and neutron powder diffraction (NPD) data. Magnetization measurements suggest the coexistence of ferromagnetic and antiferromagnetic interactions: magnetization versus magnetic field curves present a remnant magnetization in the ordered region, which is around 1 µBat T= 6 K. The thermal evolution of the magnetic structure has been followed down to 1.5 K from the NPD data. These measurements show that the Mn sub-lattice becomes ordered below TN 78 K with a spin arrangement (Cx ,Fy ,0), in such a way that a ferromagnetic component appears along the y -direction. The Nd sub-lattice becomes ordered below T 13 K according to a ferromagnetic arrangement with the moments parallel to the y -direction. At T= 1.5 K the magnetic moment values are 3.22(9) µBfor Mn atoms and 1.2(2) µBfor Nd atoms.