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Single crystals of Na2Cu+[Cu2+3O](AsO4)2Cl (1) and Cu3[Cu3O]2(PO4)4Cl2 (2) were prepared by chemical vapor transport reactions. Both crystal structures are based upon the same [O2Cu6]8+ chains formed by corner-sharing (OCu4)6+ tetrahedra and interconnected by (TO4)3− (T = P, As) tetrahedra into porous {[OCu3](TO4)2Cl}3− frameworks. The channels within the frameworks are occupied by Na+, Cu+ and Cl− ions in the crystal structure of 1, whereas the channels in the structure of 2 contain edge-sharing CuO4Cl tetragonal pyramids. Both compounds are structurally related to the previously described synthetic Na2Cu+[Cu2+3O](PO4)2Cl and NaCu2+[Cu2+3O](PO4)2Cl. The compound 2 is structurally and chemically related to yaroshevskite, Cu3[Cu3O]2(VO4)4Cl2, a mineral discovered in volcanic fumaroles, but the two structure types are drastically different. The crystal chemical analysis of the title and related compounds allows to recognize a family of at least four compounds based upon {[OCu3](TO4)2Cl}3− frameworks with channels occupied by different chemical constituents. [ABSTRACT FROM AUTHOR]

Experimental investigations of crystallization in a family of uranyl triacetate compounds with Na, K, Rb and Cs were performed. The crystal structures of two novel Cs- and Rb-bearing tri(acetato)uranylates were solved, and the content of H2O molecules in the crystal structure of K-bearing uranyl triacetate was refined. Synthesized compounds were analyzed using IR spectroscopy and single-crystal X-ray diffraction. Crystal chemical analysis of the M[(UO2)(CH3COO)3](H2O)n family (M = Na, K, Rb, Cs; n = 0–1.0) reveals the sequence of structural transformations depending on the size of alkali cation resulting in the symmetry reduction from cubic P 213 (for Na), through tetragonal I 41/a (for K and Rb) to triclinic P 1̅ space groups (for Cs), which is in accordance with the principle of morphotropism, suggested by Paul von Groth, founder of the Zeitschrift für Krystallographie journal, in 1870. [ABSTRACT FROM AUTHOR]

Single crystals of new Mn2[Bi2O](SeO3)4 (I), MnBi(SeO3)2Cl (II), MnIIMnIII(SeO3)2Cl (III), Mn5(SeO3)2Cl6 (IV), and Mn4(Mn5,Bi)(SeO3)8Cl5 (V) have been synthesized by chemical vapour transport and hydrothermal methods. They have been structurally characterized by single crystal X-ray diffraction analysis. The compounds II–V are the first Mn selenite chlorides, while the I, II and V compounds are the first Bi-containing Mn oxoselenites. Structural relationships of the new phases with other compounds are discussed. An overview of the mixed-ligand MnOmCln polyhedra in inorganic compounds is given. [ABSTRACT FROM AUTHOR]

Complexity is one of the important characteristics of crystal structures, which can be measured as the amount of Shannon information per atom or per unit cell. Since complexity may arise due to combination of different factors, herein we suggest a method of ladder diagrams for the analysis of contributions to structural complexity from different crystal-chemical phenomena (topological complexity, superstructures, modularity, hydration state, etc.). The group of minerals and inorganic compounds based upon the batagayite-type [M(TO4)Ï•] layers (M = Fe, Mg, Mn, Ni, Zn, Co; T = P, As; Ï• = OH, H2O) is used as an example. It is demonstrated that the method allows for the quantitative estimates of various contributions to the complexity of the whole structure. [ABSTRACT FROM AUTHOR]

Single crystals of two novel uranyl sulfates and two novel uranyl selenates with protonated cyclen and 3-aminotropane molecules, ((C8H24N4)[(UO2)3(SO4)5](H2O)3 (I), (C8H24N4)(H5O2)(H3O)[(UO2)4(SeO4)7(H2O)](H2O)6.6 (II), (C8H18N2)(H5O2)(H3O)[(UO2)3(SO4)5(H2O)](H2O)0.5 (III), and (C8H18N2)(H5O2)(H3O)[(UO2)3(SeO4)5 (H2O)](H2O)2 (IV) have been prepared by isothermal evaporation from aqueous solutions and structurally characterized. Uranyl-containing 2D units have been investigated using topological approach and information-based complexity measures demonstrating that complex topologies form more rare than their simplest counterparts, which is a response of the crystal structure to changes of chemical conditions within the system. [ABSTRACT FROM AUTHOR]

The crystal structure of Cs2CuP2O7 [monoclinic, Cc, a = 7.460(6), b = 12.973(10), c = 9.980(8) Åβ = 111.95(2) ° , V = 895.8(12) Å3] prepared by solid-state reactions is based upon open framework formed by corner sharing between CuO4 distorted squares and P2O7 groups. The framework is porous and has a very low framework density of 13.4 Cu+P atoms per 1 nm3. Cs+ cations reside in large framework cavities. The heteropolyhedral network in the title compound is based upon three-dimensional (3;4)-connected net that has a three-membered CuP2 ring as its elementary unit. In terms of reticular chemistry, this net should be considered as an augmented diamond (dia) net. The Cu-P net can be obtained from the latter by the replacement of its nodes by the CuP2 triangles. This replacement is strongly non-centrosymmetric, since all CuP2 triangles are oriented along the same direction, which provides a crystal chemical explanation for the absence of a symmetry centre in the structure. Cs2CuP2O7 is the first compound in the A2CuP2O7 family (A alkaline metal), which is based upon threedimensional copper pyrophosphate framework. [ABSTRACT FROM AUTHOR]

In this contribution, we briefly review the results of collaborative research between crystallography groups in St. Petersburg and Kiel, and report on the synthesis and crystal structure of Tl16(SiO4)2(SO4)(OH)6 ( 1), a new and unusual compound obtained from highly-alkaline TlOH solution. Its structure [monoclinic, C2/ m, a = 28.7140(18), b = 7.3686(5), c = 7.4426(5) Å, β = 104.653(2)°, V = 1523.50(17) Å3, R1 = 0.066 for 1528 independent observed reflections] can be described as an alternation of electroneutral [Tl5(SiO4)(OH)] and [Tl3(SO4)0.5(OH)2] layers. The [Tl5(SiO4)(OH)] layer consists of Tl(1)O4 tetragonal pyramids sharing common corners with the SiO4 tetrahedra to form pseudotetragonal [Tl(SiO4)]3- layers capped by OH(1)-centered [(OH)Tl4] square pyramids with the Tl(2) and Tl(3) atoms in their apices. The [Tl3(SO4)0.5(OH)2] layers contain OH(2)- and OH(3)-centered [(OH)Tl4] square pyramids sharing common edges to form large (∼ 7.4 × 7.4 Å) cavities occupied by disordered (SO4) tetrahedra. The electroneutral character of the [Tl5(SiO4)(OH)] and [Tl6(SO4)(OH)4] layers allows us to suggest that the phases with these chemical compositions may form as independent compounds in highly alkaline Tl-bearing systems. [ABSTRACT FROM AUTHOR]

In this contribution, we briefly review the results of collaborative research between crystallography groups in St. Petersburg and Kiel, and report on the synthesis and crystal structure of Tl16(SiO4)2(SO4)(OH)6 ( 1), a new and unusual compound obtained from highly-alkaline TlOH solution. Its structure [monoclinic, C2/ m, a = 28.7140(18), b = 7.3686(5), c = 7.4426(5) Å, β = 104.653(2)°, V = 1523.50(17) Å3, R1 = 0.066 for 1528 independent observed reflections] can be described as an alternation of electroneutral [Tl5(SiO4)(OH)] and [Tl3(SO4)0.5(OH)2] layers. The [Tl5(SiO4)(OH)] layer consists of Tl(1)O4 tetragonal pyramids sharing common corners with the SiO4 tetrahedra to form pseudotetragonal [Tl(SiO4)]3- layers capped by OH(1)-centered [(OH)Tl4] square pyramids with the Tl(2) and Tl(3) atoms in their apices. The [Tl3(SO4)0.5(OH)2] layers contain OH(2)- and OH(3)-centered [(OH)Tl4] square pyramids sharing common edges to form large (∼ 7.4 × 7.4 Å) cavities occupied by disordered (SO4) tetrahedra. The electroneutral character of the [Tl5(SiO4)(OH)] and [Tl6(SO4)(OH)4] layers allows us to suggest that the phases with these chemical compositions may form as independent compounds in highly alkaline Tl-bearing systems. [ABSTRACT FROM AUTHOR]