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Cs+ Cations (cs+ + cation)
Selected AbstractsA novel In3O16 fragment in Cs3In3(PO4)4ACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2010Igor V. Zatovsky The double phosphate Cs3In3(PO4)4, prepared by a flux technique, features a fragment of composition In3O16 formed by three corner-sharing InO6 polyhedra. The central In atom resides on a twofold rotation axis, while the other two In atoms are on general positions. The O atoms in this fragment also belong to PO4 tetrahedra, which link the structure into an overall three-dimensional anionic In,O,P network that is penetrated by tunnels running along c. Two independent Cs+ cations reside inside the tunnels, one of which sits on a centre of inversion. In general, the organization of the framework is similar to that of K3In3(PO4)4, which also contains an In3O16 fragment. However, in the latter case the unit consists of one InO7 polyhedron and one InO6 polyhedron sharing an edge, with a third InO6 octahedron connected via a shared corner. Calculations of the Voronoi,Dirichlet polyhedra of the alkali metals give coordination schemes for Cs of [9+2] and [8+4] ( symmetry), and for K of [8+1], [7+2] and [7+2]. This structural analysis shows that the coordination requirements of the alkali metals residing inside the tunnels cause the difference in the In3O16 geometry. [source] Two caesium vanadium hydrogenphosphates with tunnelled structures: Cs2V2O3(PO4)(HPO4) and Cs2[(VO)3(HPO4)4(H2O)]·H2OACTA CRYSTALLOGRAPHICA SECTION C, Issue 2 2010Romain Gautier Dicaesium divanadium trioxide phosphate hydrogenphosphate, Cs2V2O3(PO4)(HPO4), (I), and dicaesium tris[oxidovanadate(IV)] hydrogenphosphate dihydrate, Cs2[(VO)3(HPO4)4(H2O)]·H2O, (II), crystallize in the monoclinic system with all atoms in general positions. The structures of the two compounds are built up from VO6 octahedra and PO4 tetrahedra. In (I), infinite chains of corner-sharing VO6 octahedra are connected to V2O10 dimers by phosphate and hydrogenphosphate groups, while in (II) three vanadium octahedra share vertices leading to V3O15(H2O) trimers separated by hydrogenphosphate groups. Both structures show three-dimensional frameworks with tunnels in which Cs+ cations are located. [source] Multinuclear magnetic resonance, electrospray ionization,mass spectroscopy, and parametric method 5 studies of a new derivative of gossypol with 2-thiophenecarbohydrazide as well as its complexes with LI+, Na+, K+, RB+, and Cs+ cationsBIOPOLYMERS, Issue 3 2006Piotr Przybylski Abstract A new derivative of racemic gossypol with 2-thiophenecarbohydrazide (GHHT) and its complexes with monovalent cations have been synthesized and studied by electrospray ionization,mass spectroscopy (ESI-MS), multinuclear nuclear magnetic resonance (NMR), as well as by the Parametric Method 5 (PM5) methods. It is demonstrated that GHHT forms stable complexes of 1:1 stoichiometry with monovalent metal cations. The structures of the complexes are stabilized by three types of intramolecular hydrogen bonds. The spectroscopic methods have provided clear evidence that GHHT and its complexes exist in the DMSO-d6 solution in the N-imine,N-imine tautomeric forms. The structures of the GHHT and its complexes with Li+, Na+, K+, Rb+, and Cs+ cations are visualized and discussed in detail. © 2006 Wiley Periodicals, Inc. Biopolymers 83: 213,225, 2006 This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com [source] | ||||||||||