Structure,stoichiometry and phase purity of strontium-doped lanthanum manganite powders

Strontium-doped lanthanum manganite La_{1, x} Sr _x MnO₃ (LSM) is characterized by hexagonal-rhombohedral distorted perovskite-type structure, deriving from the ideal cubic symmetry through rotation of the MnO₆] octahedra around the ternary axis. The extent of distortion and unit cell volume depend on Sr content. The linear variation of the unit cell volume, observed in the compositional range 0.1 x 0.5, can be effectively used for determining the stoichiometry of LSM. A procedure for the quantitative analysis of segregated impurities (La₂O₃ and Mn₃O₄) based on X-ray powder diffraction analysis, has also been developed.