Synthesis and crystal structure of Cs2[(UO2)2(C2O4)3] and Cs2[UO2(C3H2O4)2] · H2O

Cs 2 [(UO 2 ) 2 (C 2 O 4 ) 3 ] ( I ) and Cs 2 [UO 2 (C 3 H 2 O 4 ) 2 ] · H 2 O ( II ) have been synthesized and studied by X-ray diffraction. The crystals of complexes I and II are monoclinic: a = 8.1453(2) Å, b = 8.9831(2) Å, c = 11.3897(4) Å, β = 104.0950(10)°, V = 808.29(4) Å 3 , space group P 2 1 / n , Z = 2, and R 1 = 0.0255 for I and a = 9.6998(2) Å, b = 17.8686(3) Å, c = 8.2074(2) Å, β = 97.5780(10)°, V = 1410.10(5) Å 3 , space group P 2 1 / c , Z = 4, and R 1 = 0.0287 for II . The uranium-containing structural units of complexes I and II are [(UO 2 ) 2 (C 2 O 4 ) 3 ] 2− chains and [UO 2 (C 3 H 2 O 4 ) 2 ] 2 4− dimers, which belong to the AK 0.5 02 T 11 and AT 11 B 01 crystallochemical groups (A = UO 2 2+ , K 02 and T 11 = C 2 O 4 2− , T 11 and B 01 = C 3 H 2 O 4 2− ) of uranyl complexes.