Crystal structure of BaMo3O10 solved from powder diffraction data

The crystal structure of BaMo3O10 has been determined from X-ray and neutron powder diffraction data using no prior structural information. Direct methods and combined X-ray and neutron Rietveld refinements were used to solve the structure. There are two Ba, six Mo and twenty O atoms in the asymmetric unit. The crystal symmetry is monoclinic (space group P21; Z = 4), and the unit cell parameters are a = 14.695(2) Å, b = 7.5704(7) Å, c = 6.9618(6) Å, and β = 100.381(8)°. In a combined Rietveld refinement with 124 variables, the RF -values 0.034 and 0.046 were obtained for neutron time-of-flight and X-ray data respectively, although small oscillations in some parameters could not be avoided in the final refinement cycles. The structure is built of layers of [Mo3O10 2−] linked to each other with barium ions. The Mo–O framework contains distorted MoO6 octahedra interlinked by corner- and edge-sharing.