Structure of the mixed oxides La0.6Pb0.4Mn1−yTiyO3±z (0 < y < 0.4) via Rietveld refinements

The crystal structure of several compositions in the system La0.6Pb0.4Mn1−yTiyO3 (0 ≤ y ≤ 0.4) have been investigated by powder X-ray diffraction using the Rietveld refinement technique. The solid solutions of compositions y = 0.1, 0.2, and 0.3 crystallize in the rhombohedral structure (space group R3c), while for the composition corresponding to y = 0.4, the crystal structure transforms from rhombohedral to orthorhombic system (space group Imma). Profile refinements on all these compositions reveal that the MnO6 octahedra are distorted and rotated from their ideal positions. The doping at the B-site results in the formation of the orthorhombic phase Imma at room temperature. The structural implications on the magnetic properties also correlate with previous observations.