Halogen bonding in uranyl and neptunyl trichloroacetates with alkali metals and improved crystal chemical formulae for coordination compounds.

The structures of the single crystals of compounds KUO(tca)(tcaH) (I), KNpO(tca)(tcaH)(HO) (II), RbUO(tca)(tcaH)(HO) (III), and CsUO(tca)(tcaH)·HO (IV), where tca is the trichloroacetate ion, were established by X-ray diffraction analysis. The crystals of II-IV have a framework structure, whereas in the layered crystals of I, neighboring layers are connected to each other via halogen bonds. In this regard, the crystals of I possess perfect cleavage along the (001) plane: the crystals are easily cut into stacks of very thin layers.

Peculiarities of the Supramolecular Assembly of Tetraethylammonium and 3-Bromopropionate Ions in Uranyl, Neptunyl, and Plutonyl Coordination Compounds.

Synthesis and X-ray diffraction studies of {N(CH)}[AnO(CHBrCOO)] [An = U (), Np (), or Pu ()] and CHBrCOOH (), where CHBrCOO is an anion of the 3-bromopropionic acid, are reported. The isostructural coordination compounds - contain mononuclear anionic complexes [AnO(CHBrCOO)] belonging to the crystal chemical group AB (A = AnO; B = CHBrCOO). In the crystal structure of , the CHBrCOOH molecules are hydrogen bonded into centrosymmetric dimers R(8).

Aspects of the topology of actinide atom substructures in crystal structures and the concept of antiliquid.

Using the parameters of Voronoi-Dirichlet (VD) polyhedra the authors have verified the maximum space-filling principle in substructures constructed of actinide atoms (from thorium to einsteinium) in all crystal structures from the Inorganic Crystal Structure Database (ICSD) and Cambridge Structural Database (CSD). It is shown that most of the actinide atoms in such substructures are surrounded by 14 or 12 neighboring atoms. It was discovered that U substructures with greater than or equal to 20 crystallographically independent U atoms in the unit cell feature 15-faceted VD polyhedra as the most common type.

A method for visualization of the variation of noncovalent interactions in crystal structures of conformational polymorphs.

A method for clear visualization of the variation of noncovalent interactions in crystal structures of conformational polymorphs is developed and introduced. The first stage of the method establishes the characteristics of all, without exception, noncovalent interactions in all crystal structures under discussion. This is possible using a strict and objective method of construction of Voronoi-Dirichlet polyhedra within the framework of the stereoatomic model of crystal structures.

Crystal structures of uranyl complexes with isobutyrate and isovalerate anions.

Single crystals of Na[(UO)(i-CHCOO)]·0.7HO (I), Cs[(UO)(i-CHCOO)] (II) and (NH)[(UO)(i-CHCOO)] (III) were obtained via isothermal evaporation and their structures were solved using X-ray diffraction techniques. Even though the ligands are branched, bulky and spatial, many carbon and hydrogen atoms are still disordered in these crystal structures at low temperature.

Syntheses, Crystal Structures, and Nonlinear Optical Activity of CsBa[AnO(CHCOO)] (An = U, Np, Pu) and Unprecedented Octanuclear Complex Units in KR(HO)[UO(CHCOO)] (R = Sr, Ba).

X-ray diffraction was applied to the elucidation of crystal structures of single crystals of CsBa[AnO(CHCOO)], where An = U(I), Np(II), Pu(III), and KR(HO)[UO(CHCOO)], where R = Sr(IV), Ba (polymorphs V-a and V-b). FTIR spectra were analyzed for the uranium-containing crystals I, IV, and V-b. Isostructural cubic crystals I-III are constructed of typical mononuclear anionic complex units [AnO(CHCOO)] and charge-balancing Cs and Ba cations.

Synthesis and X-ray Crystallography of [Mg(H2O)6][AnO2(C2H5COO)3]2 (An = U, Np, or Pu).

Synthesis and X-ray crystallography of single crystals of [Mg(H2O)6][AnO2(C2H5COO)3]2, where An = U (I), Np (II), or Pu (III), are reported. Compounds I-III are isostructural and crystallize in the trigonal crystal system. The structures of I-III are built of hydrated magnesium cations [Mg(H2O)6](2+) and mononuclear [AnO2(C2H5COO)3](-) complexes, which belong to the AB(01)3 crystallochemical group of uranyl complexes (A = AnO2(2+), B(01) = C2H5COO(-)).

The first uranyl complexes with valerate ions.

FT-IR spectroscopy and single-crystal X-ray structure analysis were used to characterize the discrete neutral compound diaquadioxidobis(n-valerato-κ(2)O,O')uranium(VI), [UO2(C4H9COO)2(H2O)2], (I), and the ionic compound potassium dioxidotris(n-valerato-κ(2)O,O')uranium(VI), K[UO2(C4H9COO)3], (II). The U(VI) cation in neutral (I) is at a site of 2/m symmetry. Potassium salt (II) has two U centres and two K(+) cations residing on twofold axes, while a third independent formula unit is on a general position.

Voronoi-Dirichlet tesselation as a tool for investigation of polymorphism in molecular crystals with CwHxNyOz composition and photochromic properties.

The non-bonded interactions in five sets of polymorph substances with photochromic properties have been investigated within the Voronoi-Dirichlet approach. Twenty compounds with the general formula C(w)H(x)N(y)O(z) were analyzed. Among ten possible types of non-bonded interactions at least five types are observed in the crystal structures of compounds under discussion.

Crystallochemical formula as a tool for describing metal-ligand complexes - a pyridine-2,6-dicarboxylate example.

Compounds (299) containing 494 symmetrically independent pyridine-2,6-dicarboxylate moieties have been investigated. Among them the structures of Na(3)[Nd(Pydc)(3)].14H(2)O and Na(3)[Er(Pydc)(3)].