caa a22 4500 378882287 CHVBK 20180305123434.0 cr unu---uuuuu 161128e20031101xx s 000 0 eng 10.1524/zkri.218.11.725.20298 doi (NATIONALLICENCE)gruyter-10.1524/zkri.218.11.725.20298 Structural topology of potassium uranyl chromates: crystal structures of K8[(UO2)(CrO4)4](NO3)2, K5[(UO2)(CrO4)3](NO3)(H2O)3, K4[(UO2)3(CrO4)5](H2O)8 and K2[(UO2)2(CrO4)3(H2O)2](H2O)4 [Elektronische Daten] [Sergey V. Krivovichev, Peter C. Burns] Crystals of four potassium uranyl chromates, K8[(UO2)(CrO4)4](NO3)2 (1), K5[(UO2)(CrO4)3](NO3)·(H2O)3 (2), K4[(UO2)3(CrO4)5](H2O)8 (3) and K2[(UO2)2·(CrO4)3(H2O)2](H2O)4 (4), have been synthesized by evaporation of aqueous solutions of (UO2)(NO3)2(H2O)6 and K2CrO4. The structure of (1) (triclinic, P1̅, a = 7.0397(6), b = 9.7341(9), c = 9.7568(9) Å, α = 105.846(2), β = 97.992(2), γ = 93.271(2)°, V = 633.8(1) Å3, Z = 1) was solved by direct methods and refined to R1 = 0.044 (wR2 = 0.098). It is based upon clusters of composition [(UO2)(CrO4)4] that consist of UrO4 square bipyramids (Ur: UO22+ uranyl ion) that share corners with four different CrO4 tetrahedra. The clusters are arranged in layers parallel to the (100) plane. K+ cations and NO3- groups are located between the clusters. The crystal structure of (2) (orthorhombic, P212121, a = 6.1112(11), b = 12.136(2), c = 27.464(4) Å, V = 2036.9(6) Å3, Z = 4) was solved by direct methods and refined to R1 = 0.047 (wR2 = 0.071). it contains chains of composition [(UO2)(CrO4)3] that are parallel to the b axis. The chains consist of UrO5 pentagonal bipyramids that share all equatorial corners with different CrO4 tetrahedra. Planes containing the equatorial ligands of the UrO5 pentagonal bipyramids are approximately parallel to the (100) plane. K+ cations, NO3 groups and H2O groups are between the chains. The crystal structure of (3) (monoclinic, P21/c, a = 8.2336(7), b = 18.8042(17), c = 21.2413(18) Å, β = 89.979(2)°, V = 3288.7(5) Å3, Z = 4) has been solved by direct methods from a crystal twinned on the (001) plane and refined to R1 = 0.060 (wR2 = 0.125). The structure is based upon topologically complex sheets of composition [(UO2)3(CrO4)5] with UrO5 pentagonal bipyramids that share their corners with CrO4 tetrahedra. The sheets are parallel to the (010) plane. K+ cations and H2O groups are located in the interlayer between the sheets. The crystal structure of (4) (monoclinic, P21/c, a = 10.7417(5), b = 14.5290(7), c = 14.1387(6) Å, β = 108.135(1)°, V = 2097.0(2) Å3, Z = 4) was solved by direct methods and refined to R1 = 0.036 (wR2 = 0.067). It is based upon sheets of composition [(UO2)2(CrO4)3(H2O)2] that are parallel to the (010) plane. K+ cations and additional H2O groups are in the interlayer. Nodal representations of uranyl chromate structural units are developed, and a comparison with related structures are presented. © 2003 Oldenbourg Wissenschaftsverlag GmbH Crystallography nationallicence Inorganic chemistry nationallicence Organic chemistry nationallicence Krivovichev Sergey V. aut Burns Peter C. aut Zeitschrift für Kristallographie - Crystalline Materials De Gruyter Oldenbourg 218/11(2003-11-01), 725-732 2194-4946 218:11<725 2003 218 zkri https://doi.org/10.1524/zkri.218.11.725.20298 text/html Onlinezugriff via DOI 1 research article jats NATIONALLICENCE 856 40 https://doi.org/10.1524/zkri.218.11.725.20298 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Krivovichev Sergey V. aut NATIONALLICENCE 700 1- Burns Peter C. aut NATIONALLICENCE 773 0- Zeitschrift für Kristallographie - Crystalline Materials De Gruyter Oldenbourg 218/11(2003-11-01), 725-732 2194-4946 218:11<725 2003 218 zkri CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-gruyter