STRUCTURE DETERMINATION OF LIMOP2O7 FROM MULTIPHASE POWDER X-RAY-DIFFRACTION DATA

The crystal structure of LiMoP2O7 was determined from conventional powder X-ray diffraction at room temperature in the presence of MoP2O7, MoO2 and Mo as impurities. Pattern decomposition was employed to eliminate complex contaminants prior to the Rietveld structure refinement. LiMoP2O7 crystallizes in the space group P2(1) with Z = 2, a = 4.8987 (3), b = 8.3912 (4), c = 7.0306 (4) angstrom, beta- = 109.327 (4)-degrees, V = 272.71 angstrom3. Final agreement indicators were R(p) = 0.0589, R(wp) = 0.0772, R(f) = 0.054 and R(I) = 0.080. The framework of the structure consists of corner-sharing MoO6 octahedra and P2O7 groups, which form tunnels where the Li cations are located. The results give an example of analyzing a structure from a tetraphasic mixture using pattern decomposition in conjunction with the Rietveld refinement method.