Crystal chemistry of anhydrous Li uranyl phosphates and arsenates. II. Tubular fragments and cation-cation interactions in the 3D framework structures of Li{sub 6}[(UO{sub 2}){sub 12}(PO{sub 4}){sub 8}(P{sub 4}O{sub 13})], Li{sub 5}[(UO{sub 2}){sub 13}(AsO{sub 4}){sub 9}(As{sub 2}O{sub 7})], Li[(UO{sub 2}){sub 4}(AsO{sub 4}){sub 3}] and Li{sub 3}[(UO{sub 2}){sub 7}(AsO{sub 4}){sub 5}O]

Journal Article · Sun Nov 15 00:00:00 EST 2009 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2009.08.003· OSTI ID:21372375

Krivovichev, Sergey V ^[1]; Depmeier, Wulf ^[2]

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1. Department of Crystallography, St. Petersburg State University, 199034 St. Petersburg (Russian Federation)
2. Institut fuer Geowissenschaften, Universitaet Kiel, D-24118 Kiel (Germany)

Single crystals of the new compounds Li{sub 6}[(UO{sub 2}){sub 12}(PO{sub 4}){sub 8}(P{sub 4}O{sub 13})] (1), Li{sub 5}[(UO{sub 2}){sub 13}(AsO{sub 4}){sub 9}(As{sub 2}O{sub 7})] (2), Li[(UO{sub 2}){sub 4}(AsO{sub 4}){sub 3}] (3) and Li{sub 3}[(UO{sub 2}){sub 7}(AsO{sub 4}){sub 5}O)] (4) have been prepared using high-temperature solid state reactions. The crystal structures have been solved by direct methods: 1-monoclinic, C2/m, a=26.963(3) A, b=7.063(1) A, c=19.639(1) A, beta=126.890(4){sup o}, V=2991.2(6) A{sup 3}, Z=2, R{sub 1}=0.0357 for 3248 unique reflections with |F{sub 0}|>=4sigma{sub F}; 2-triclinic, P1-bar, a=7.1410(8) A, b=13.959(1) A, c=31.925(1) A, alpha=82.850(2){sup o}, beta=88.691(2){sup o}, gamma=79.774(3){sup o}, V=3107.4(4) A{sup 3}, Z=2, R{sub 1}=0.0722 for 9161 unique reflections with |F{sub 0}|>=4sigma{sub F}; 3-tetragonal, I4{sub 1}/amd, a=7.160(3) A, c=33.775(9) A, V=1732(1) A{sup 3}, Z=4, R{sub 1}=0.0356 for 318 unique reflections with |F{sub 0}|>=4sigma{sub F}; 4-tetragonal, P4-bar, a=7.2160(5) A, c=14.6540(7) A, V=763.04(8) A{sup 3}, Z=1, R{sub 1}=0.0423 for 1600 unique reflections with |F{sub 0}|>=4sigma{sub F}. Structures of all the phases under consideration are based on complex 3D frameworks consisting of different types of uranium polyhedra (UO{sub 6} and UO{sub 7}) and different types of tetrahedral TO{sub 4} anions (T=P or As): PO{sub 4} and P{sub 4}O{sub 13} in 1, AsO{sub 4} and As{sub 2}O{sub 7} in 2, and single AsO{sub 4} tetrahedra in 3 and 4. In the structures of 1 and 2, UO{sub 7} pentagonal bipyramids share edges to form (UO{sub 5}){sub i}nfinity chains extended along the b axis in 1 and along the a axis in 2. The chains are linked via single TO{sub 4} tetrahedra into tubular units with external diameters of 11 A in 1 and 11.5 A in 2, and internal diameters of 4.1 A in 1 and 4.5 A in 2. The channels accommodate Li{sup +} cations. The tubular units are linked into 3D frameworks by intertubular complexes. Structures of 3 and 4 are based on 3D frameworks composed on layers united by (UO{sub 5}){sub i}nfinity infinite chains. Cation-cation interactions are observed in 2, 3, and 4. In 2, the structure contains a trimeric unit with composition [O=U(1)=O]-U(13)-[O=U(2)=O]. In the structures of 3 and 4, T-shaped dimers are observed. In all the structures, Li{sup +} cations are located in different types of cages and channels and compensate negative charges of anionic 3D frameworks. - Graphical abstract: The crystal structures of Li{sub 5}[(UO{sub 2}){sub 13}(AsO{sub 4}){sub 9}(As{sub 2}O{sub 7})] separated into tubular units and intertubular complexes.

• OSTI ID: 21372375
• Journal Information: Journal of Solid State Chemistry, Vol. 182, Issue 11; Other Information: DOI: 10.1016/j.jssc.2009.08.003; PII: S0022-4596(09)00380-6; Copyright (c) 2009 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ARSENATES
CATIONS
LITHIUM IONS
MONOCLINIC LATTICES
MONOCRYSTALS
TETRAGONAL LATTICES
URANYL PHOSPHATES
ACTINIDE COMPOUNDS
ARSENIC COMPOUNDS
CHARGED PARTICLES
CRYSTAL LATTICES
CRYSTAL STRUCTURE
CRYSTALS
IONS
OXYGEN COMPOUNDS
PHOSPHATES
PHOSPHORUS COMPOUNDS
URANIUM COMPOUNDS
URANYL COMPOUNDS