Xrd Analysis On Lattice Structure Of La1-Xtexmno3

Based on X-ray powder diffraction data, the lattice structure and symmetry of La1-xTexMnO3 (0.04 <= x <= 0.2) have been analyzed by Rietveld refining method. the results show that all samples structure have a rhombohedral symmetry with space group R(3) over bar C, and the lattice of MnO6 octahedron has a stretching distortion due to the difference in cation size. Besides, the degree Of structure distortion is closely related to Te content and can be depicted with the following three factors: the Mn-O-Mn bond angle theta(Mn-O-Mn), the average A-site radius < r(A)> and the A-site size mismatch sigma(2). According to the changing trend of these factors, several conjecture on physical properties are discussed, including the Curie temperature, spin-glass and phase separation etc.