POWDER NEUTRON-DIFFRACTION STUDY OF THE MIXED URANIUM VANADIUM-OXIDES CS2(UO2)2(V2O8) AND UVO5

The crystal structures of UVO5 [space group Pbcm, a = 4.1231(1) angstrom, b = 12.3641(1) angstrom, c = 7.2071(1) angstrom, Z = 4] and CS2(UO2)2V2O8 [space group P2(1)/a, a = 10.521(2) angstrom, b = 8.4369(9) angstrom, c = 7.308(3) angstrom, beta = 106.08(1)-degrees, Z = 2], previously obtained by single-crystal X-ray diffraction, were refined using powder neutron diffraction and Rietveld analysis adapted to time-of-flight data. The main structural features of the two compounds were confirmed but more accurate oxygen positions are reported here