CRYSTAL CHEMISTRY OF URANYL MOLYBDATES. VI. NEW URANYL MOLYBDATE UNITS IN THE STRUCTURES OF Cs4[(UO2)3O(MoO4)2(MoO5)] AND Cs6[(UO2)(MoO4)4

Abstract

Two Cs uranyl molybdates, Cs4[(UO2)3O(MoO4)2(MoO5)] and Cs6[(UO2)(MoO4)4], have been synthesized by hightemperature solid-state reactions. The structures of these compounds were solved by direct methods and refined on the basis of F 2 for all unique data collected with monochromatic MoK X-radiation and a CCD (charge-coupled device) detector. The structure of Cs4[(UO2)3O(MoO4)2(MoO5)] was refined to an agreement factor ( R1) of 4.4%, calculated using the 4873 unique observed reflections (Fo ≥ 4F). It is triclinic, space group P1, a 7.510(2), b 7.897(2), c 9.774(2) A, 79.279(5), 81.269(5), 87.251(5)°, V 562.8(2) A 3 , Z = 1. The structure of Cs 6[(UO2)(MoO4)4] was refined to an R1 of 4.9%, calculated using the 4275 unique