Packing of complex anions and effect of mutual ordering of heavy cations in structures with the paratungstate ion [H2W12O42]10−

The packing of [H ₂W₁₂O₄₂]¹⁰⁻ polyanions in seven known crystal structures is analyzed. The centers of the polyanions are arranged according to the law of the F- cell (3 cases) or I- cell (2 cases) or according to a more complex law. “Coherence” in the arrangement of heavy W atoms belonging to different polyanions is established: there are crystallographic planes with high concentrations of these atoms;this is an effect of superstructural ordering up to formation of the cation sublattice with light “filler” atoms (K, Mg, Na, N) partly addressed to the sites of the sublattice. Translated fromZhumal Strukturnoi Khimii, Vol. 38, No. 4, pp. 732–738, July–August, 1997.     

Characteristic features of crystal chemistry of natural mercury-containing sulfides and sulfosalts

Many mercury-containing minerals belonging to the class of sulfides and sulfosalts are based on a highly symmetric sphalerite type structure (ZnS), where both components occupy sites with high point symmetry providing stable orientation of directed interatomic interactions. Some structures of natural compounds of this type are used to demonstrate that the geometric matrix of cations and anions tends to be preserved during variation of the chemical composition caused by migration of elements under natural conditions. The fundamental laws of crystal formation are confirmed: the governing role of the families of close packed (crystallographic) planes, the independence of ordering of different types of atoms, the tendency of sulfur atoms to mirror plane symmetry, and the trend to cluster formation in the development of crystal structures, as exemplified by [As₄S₁₂]¹²⁻, [(Cs,Tl)S₁₂]²³⁻, [Tl₂S₁₂]²²⁻ atomic groups.     

Mirror plane as a regulator of the crystal structure of sulfides. rare-earth element sesquisulfides

A CAS-PAN analysis (isolation of close-packed atomic planes) of three most widespread structural types of rare-earth sesquisulfides — monoclinic Ho₂S₃ and orthorhombic Gd₂S₃ and Tm₂S₃ — showed that mirror plane systems separated by 2 å in sulfide structures often contain trigonal nets of both cations and anions filled according to the “splitting” principle. The mirror plane forces all atoms into one plane and thus actually deprives them of one of the three degrees of freedom, stabilizing the one-layer hexagonal packing in which the basal plane is split into two mutually complementary planes (AA’ type).     

A novel rhenium-aqua structure: the synthesis and structural characterization of (PPh4)4[ReN(H2O)(CN)3-μ-CN-ReN(CN)4]?·?5H2O

A novel cyano bridged rhenium nitrido complex, [ReN(H₂O)(CN)₄-μ-CN-ReN(CN)₄]⁴⁻ (I) was isolated during a kinetic study of the reaction of ReN(H₂O)(CN)₄]²⁻ with pyridine-2,3-dicarboxylic acid. Yellow crystals of (I), suitable for X-ray structure determination were isolated and the structural data showed an unsymmetrical binuclear rhenium complex with a cyano ligand acting as a bridge between two metal atoms, Re(1) and Re(2). The nitrogen of the bridged cyano ligand coordinates trans to the nitrido ligand of Re(1). The rhenium-nitrido bond distances are 1.657(4) and 1.656(5) ? for Re(1)–N(9) and Re(2)–N(10) respectively. Re(1) and Re(2) are displaced from the planes formed by the four carbon atoms of the cyano ligands towards the nitrido ligands by 0.348(2) and 0.3403(2) ?, respectively.     

Low‐dimensional compounds containing cyano groups. XII.)copper(II) perchlorate

The title compound, [Cu(C₂N₃)(C₃H₁₀N₂)₂]ClO₄, is made up of [Cu(tn)₂{N(CN)₂}]⁺ complex cations (tn is 1,3‐diamino­propane) and ClO₄⁻ anions. The Cu^II atom is coordinated by four N atoms of two equatorial tn ligands, with an average distance of 2.041 (7) Å, and one nitrile N atom of the dicyanamide anion in an axial position, at a distance of 2.236 (3) Å, in a manner approaching square‐planar coordination geometry. The complex has C_s symmetry, with the mirror plane lying through the central C atoms of both tn ligands and the dca ligand. The ClO₄⁻ anion might be considered as very weakly coordinated in the opposite axial position [Cu—O = 2.705 (3) Å], thus completing the Cu^II coordination to asymmetric elongated octa­hedral (4+1+1*). The Cu atom and the perchlorate anion both lie on mirror planes.     

KHCoP2O7·2H2O: a novel acidic pyrophosphate

Potassium cobalt hydrogenpyrophosphate dihydrate, KHCoP₂O₇·2H₂O, crystallizes in the orthorhombic space group Pnma. This salt is isotypic with KHMP₂O₇·2H₂O (M = Mn and Zn). The structure consists of alternating layers, built from HP₂O₇³⁻ acidic pyrophosphate groups and CoO₆ octahedra, joined by potassium ions and bridging hydrogen bonds. The Co, K and water O atoms lie on mirror planes. The pyrophosphate group consists of two symmetry‐related PO₄ groups, with the bridging O atom on a mirror plane.     

Tris(thianthrene)(2+) bis(dodecamethylcarba‐closo‐dodecaborate) dichloromethane tetrasolvate: a crossed triple‐decker π‐trimer dication

The title compound, (3C₁₂H₈S₂)²⁺·2C₁₃H₃₆B₁₁⁻·4CH₂Cl₂, contains an unusual cation–radical association comprising a π‐trimer dication of crossed thianthrenes. The thianthrene molecular planes are essentially cofacial, but the S...S axes of adjacent molecules are orthogonal to each other. The outer thianthrenes (both located on mirror planes bisecting the units at the S atoms) are bent slightly towards the inner and planar thianthrene (residing on a 2/m symmetry element with the S atoms on the twofold rotation axis), with close noncovalent separations of 3.1 Å indicating strong interplanar interactions within the trimeric dication. Bond‐length analysis indicates that the 2+ charge is delocalized over the three stacked thianthrenes with the maximum charge on the central unit. The crossed monomer arrangement is attributed to the frontier‐orbital symmetry that allows various π‐bonding orientations between thianthrene molecules. The CB₁₁(CH₃)₁₂⁻ counter‐ion resides on a mirror plane. One of the CH₂Cl₂ solvent molecules resides on a twofold rotation axis, whereas the other is located on a mirror plane.     

Two crown‐ether‐coordinated caesium halogen salts

The crystal structures of two crown‐ether‐coordinated caesium halogen salt hydrates, namely di‐μ‐bromido‐bis[aqua(1,4,7,10,13,16‐hexaoxacyclooctadecane)caesium(I)] dihydrate, [Cs₂Br₂(C₁₂H₂₄O₆)₂(H₂O)₂]·2H₂O, (I), and poly[[diaquadi‐μ‐chlorido‐μ‐(1,4,7,10,13,16‐hexaoxacyclooctadecane)dicaesium(I)] dihydrate], {[Cs₂Cl₂(C₁₂H₂₄O₆)(H₂O)₂]·2H₂O}_n, (II), are reported. In (I), all atoms are located on general positions. In (II), the Cs⁺ cation is located on a mirror plane perpendicular to the a axis, the chloride anion is located on a mirror plane perpendicular to the c axis and the crown‐ether ring is located around a special position with site symmetry 2/m, with two opposite O atoms exactly on the mirror plane perpendicular to the a axis; of one water molecule, only the O atom is located on a mirror plane perpendicular on the a axis, while the other water molecule is completely located on a mirror plane perpendicular to the c axis. Whereas in (I), hydrogen bonds between bromide ligands and water molecules lead to one‐dimensional chains running along the b axis, in (II) two‐dimensional sheets of water molecules and chloride ligands are formed which combine with the polymeric caesium–crown polymer to give a three‐dimensional network. Although both compounds have a similar composition, i.e. a Cs⁺ cation with a halogen, an 18‐crown‐6 ether and a water ligand, the crystal structures are rather different. On the other hand, it is remarkable that (I) is isomorphous with the already published iodide compound.     

Isostructural crystal packing and hydrogen bonding in alkyl­ammonium tin(IV) chloride compounds

The three isostructural compounds butyl­ammonium hexa­chlorido­tin(IV), pentyl­ammonium hexa­chlorido­tin(IV) and hexyl­ammonium hexa­chlorido­tin(IV), (C_nH_2n+1NH₃)₂[SnCl₆], with n = 4, 5 and 6, respectively, crystallize as inorganic–organic hybrids. As such, the structures consist of layers of [SnCl₆]²⁻ octa­hedra, separated by hydro­carbon layers of inter­digitated butyl­ammonium, pentyl­ammonium or hexyl­ammonium cations. Corrugated layers of cations alternate with tin(IV) chloride layers. The asymmetric unit in each compound consists of an anionic component comprising one Sn and two Cl atoms on a mirror plane, and two Cl atoms in general positions; the two cations lie on another mirror plane. Application of the mirror symmetry generates octa­hedral coordination around the Sn atom. All compounds exhibit bifurcated and simple hydrogen‐bonding inter­actions between the ammonium groups and the Cl atoms, with little variation in the hydrogen‐bonding geometries.     

Soft activation of the C-S bond: X-ray diffraction and spectroscopic study of the cluster Ru4(μ4-S)(μ,η3-C3H5)2(CO)12

The complex Ru₄(μ₄-S)(μ,η³-C₃H₅)₂(CO)₁₂ is prepared and examined by IR and NMR spectroscopy; its crystal structure is determined (an automatic Bruker-Nonius X8 Apex four-circle diffractometer equipped with a 2-D CCD-detector, 100 K, graphite-monochromated molybdenum source, λ = 0.71073 ?). The crystal belongs to the orthorhombic crystal system with unit cell parameters a = 19.3781(9) ?, b = 12.2898(7) ?, c = 10.1726(4) ?, V = 2422.6(2) ?³, space group Pnma, Z = 4, composition C₁₈H₁₀O₁₂Ru₄S, d _x = 2.343 g/cm³. The molecule of point symmetry C ₁ is situated on the mirror plane of the space group Pnma, two carbonyl groups at Ru2 and Ru3 atoms overlapping with the allylic ligand with a weight of 50% so that carbon atoms coincide. Thus, we have a racemic structure with two overlapping enantiomers of the molecule of Ru₄(μ₄-S)(μ,η³-C₃H₅)₂(CO)₁₂. Original Russian Text Copyright ? 2008 by I. Yu. Prikhod’ko, V. P. Kirin, V. A. Maksakov, A. V. Virovets, and A. V. Golovin __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 49, No. 4, pp. 748–752, May–June, 2008.     

catena‐Poly[bis[1‐chloromethyl‐1,4‐diazoniabicyclo[2.2.2]octane] [cadmium(II)‐tri‐μ‐chlorido‐[chloridocadmium(II)]‐di‐μ‐chlorido‐[chloridocadmium(II)]‐tri‐μ‐chlorido] tetrahydrate]

The title compound, {(C₇H₁₅N₂Cl)₂[Cd₃Cl₁₀]·4H₂O}_n, consists of 1‐chloromethyl‐1,4‐diazoniabicyclo[2.2.2]octane dications, one‐dimensional inorganic chains of {[Cd₃Cl₁₀]⁴⁻} anions and uncoordinated water molecules. Each of the two independent Cd^II ions, one with site symmetry 2/m and the other with site symmetry m, is octahedrally coordinated by chloride ions (two with site symmetry m and one with site symmetry 2), giving rise to novel polymeric zigzag chains of corner‐sharing Cd‐centred octahedra parallel to the c axis. The organic cations, bisected by mirror planes that contain the two N atoms, three methylene C atoms and the Cl atom, are ordered. Hydrogen bonds (O—H...Cl and O—H...O) between the water molecules (both with O atoms in a mirror plane) and the chloride anions of neighbouring chloridocadmate chains form a three‐dimensional supramolecular network.     

Theoretical Study of the Metal–Metal Interaction in Dipalladium(I) Complexes

Correlated ab initio calculations have been performed on three dipalladium(I) complexes. These compounds differ both by the metal–metal interaction and by the metal–ligand interaction. The [Pd₂Cl₂(μ −H₂PCH₂PH₂)₂] complex exhibits a σ overlap between the two binding metallic orbitals and has no bridging ligand. In [Pd₂Cl₄(μ −CO)₂]²⁻, the leading interaction between the two palladium involves a π overlap between the metallic orbitals and goes through the two bridging CO ligands. In [Pd₂Cl₂(μ −CO)(μ −H₂PCH₂ PH₂)₂], a single CO ligand bridges the two palladium atoms which interact through a hybrid σ–δ overlap. The three compounds also differ by the metal–metal distances. Surprisingly enough, while the palladium atoms are formally d ⁹ in all these complexes, none of them is paramagnetic. We propose here a detailed analysis of the electronic structures of these compounds and rationalize their chemical structures as well as the role of back-donation in the CO bridged compounds. Finally, since highly correlated treatments are used to describe these complexes, a detailed study of the role of both non-dynamical and dynamical correlations is performed. Concerning the [Pd₂Cl₄(μ −CO)₂]²⁻ complex, this analysis has revealed that the complex is not bound at the lowest correlated levels of calculation and therefore dynamical correlation is alone responsible for its binding energy.     

Tetra­ethyl­ammonium bis­(N,N‐diethyl­dithio­carbamato‐κ2S,S′)iodo­cadmate(II)

The title compound, (C₈H₂₀N)[Cd(C₅H₁₀NS₂)₂I], containing a heteroleptic five‐coordinate mononuclear anionic cadmium complex, crystallizes in ortho­rhom­bic form in the space group Pnma. Both anion and cation lie about mirror planes. Unlike other known [Cd(dtc)₂X]‐type complexes (where dtc is dithio­carbamate and X is a halogen or pseudohalogen), the central CdS₄I core shows a square‐pyramidal configuration, with a basal plane defined by four S atoms from two chelating dithio­carbamate ligands related by a symmetry plane. The central Cd atom is displaced from the basal S₄ plane towards the apical I atom of the square pyramid.     

Two packing motifs based upon chains of edge‐sharing PbI6 octa­hedra

The compounds catena‐poly[p‐phenyl­enediammonium [[diiodo­lead(II)]‐di‐μ‐iodo] dihydrate], {(C₆H₁₀N₂)[PbI₄]·2H₂O}_n, (I), and catena‐poly[bis­(3,5‐dimethyl­anilinium) [[diiodo­lead(II)]‐di‐μ‐iodo]], {(C₈H₁₂N)₂[PbI₄]}_n, (II), crystallize as organic–inorganic hybrids. As such, the structures consist of chains of [PbI₂]⁻ units extending along the c axis in (I) and along the b axis in (II). The asymmetric unit in (I) contains one Pb atom on a site of 2/m symmetry, two I atoms and a water molecule on mirror planes, and a p‐phenyl­enediammonium mol­ecule that sits around a site of 2/m symmetry with the C and N atoms on a mirror plane. In (II), the Pb atom is on a twofold axis and the two I atoms are on general positions. Each Pb atom is octa­hedrally coordinated to six I atoms, arranged as chains of edge‐sharing octa­hedra. Both compounds undergo hydrogen‐bonding inter­actions between the ammonium groups and the I atoms. In addition, there are hydrogen bonds between the water mol­ecules and the ammonium groups and halides in (I), and between the ammonium groups and the ring systems in (II).     

Synthesis and structure of the polymeric complex [Ag<Subscript>2</Subscript>(Ph<Subscript>3</Subscript>P)<Subscript>2</Subscript>B<Subscript>10</Subscript>H<Subscript>10</Subscript>]<Subscript><Emphasis Type="Italic">n</Emphasis></Subscript>

A method for the synthesis of the silver(I) complex with the closo-decaborate anion and triphenylphosphine [Ag₂(Ph₃P)₂B₁₀H₁₀] _n was developed and the structure of this complex was studied. The polymeric chain of the complex is formed with participation of Ag(I) atoms, which coordinate the B₁₀H₁₀²⁻ anions through the apical (B(1)–B(2), B(9)–B(10)) and equatorial (B(3)–B(6), B(5)–B(8)) edges, the metalligand bonding occurring through three-center two-electron bonds (MHB). The P atoms of two triphenylphosphine molecules are also incorporated in the inner coordination sphere of the metal: the CN of the silver atom is 4 + 1.     

Rubidium dimolybdate,Rb2Mo2O7, and caesium dimolybdate,Cs2Mo2O7

The crystal structures of dirubidium hepta­oxodimolybdate, Rb₂Mo₂O₇, and dicaesium hepta­oxodimolybdate, Cs₂Mo₂O₇, in the space groups Ama2 and P2₁/c, respectively, have been determined for the first time by single‐crystal X‐ray diffraction. The structures represent two novel structure types of monovalent ion dimolybdates, A₂Mo₂O₇ (A = alkaline elements, NH₄, Ag or Tl). In the structure of Rb₂Mo₂O₇, Mo atoms are on a twofold axis, on a mirror plane and in a general position. One of the Rb atoms lies on a twofold axis, while three others are on mirror planes. Two O atoms attached to the Mo atom on a mirror plane are located on the same plane. Rubidium dimolybdate contains a new kind of infinite Mo–O chain formed from linked MoO₄ tetra­hedra and MoO₆ octa­hedra alternating along the a axis, with two terminal MoO₄ tetra­hedra sharing corners with each octa­hedron. The chains stack in the [001] direction to form channels of an approximately square section filled by ten‐coordinate Rb ions. Seven‐ and eight‐coordinate Rb atoms are located between chains connected by a c translation. In the structure of Cs₂Mo₂O₇, all atoms are in general positions. The MoO₆ octa­hedra share opposite corners to form separate infinite chains running along the c axis and strengthened by bridging MoO₄ tetra­hedra. The same Mo–O polyhedral chain occurs in the structure of Na₂Mo₂O₇. Eight‐ to eleven‐coordinate Cs atoms fill the space between the chains. The atomic arrangement of caesium dimolybdate has an ortho­rhom­bic pseudosymmetry that suggests a possible phase transition P2₁/c→Pbca at elevated temperatures.     

One-dimensional coordination polymer of copper(I) thiocyanate with the Schiff base ligand N,N′-bis(3,4-dimethoxybenzylidene)butane-1,4-diamine: synthesis, crystal structure, spectroscopic and thermal properties

Abstract  

A new one-dimensional polymeric copper(I)–thiocyanate complex with the Schiff base ligand N,N′-bis(3,4-dimethoxybenzylidene)butane-1,4-diamine, {Cu₂((μ _N,N′ -3,4-MeO-ba)₂bn)(μ_1,3-NCS)₂} _n , was synthesized and characterized by elemental analysis, ¹H and ¹³C NMR, FT–IR spectroscopy, and thermal analysis. The thermal behavior of the complex was studied using thermogravimetry in order to evaluate thermal stability and thermal decomposition pathways. The molecular structure of the complex was determined by single-crystal X-ray diffraction which revealed that the coordination geometry around the copper(I) ion is distorted trigonal. The Schiff base ligand (3,4-MeO-ba)₂bn acts as a bis-monodentate and bridging ligand (μ _N,N′ ) and coordinates via two N atoms to the metal centers and adopts an E,E conformation. The coordination spheres of the metal atoms are completed by the N and S atoms from two thiocyanate anion bridges (μ_1,3-NCS), forming a zigzag chain propagating along [001].     

catena‐Poly[bis­(tert‐butyl­ammonium) [plumbate(II)‐tri‐μ‐iodo] iodide dihydrate]

The title compound, {(C₄H₁₂N)₂[PbI₃]I·2H₂O}_n, crystallizes as an organic–inorganic hybrid. The six‐coordinate Pb atom lies on a centre of inversion and all the I atoms lie on mirror planes; the two independent cations both lie across mirror planes. The structure contains anionic chains along [100] of fused [PbI₃]⁻ units forming face‐sharing octa­hedra. Four cations enclose channels occupied by isolated iodide ions and water mol­ecules of hydration.     

The tunnel manganese oxide Na4.32Mn9O18: a new Na+ site discovered by single‐crystal X‐ray diffraction

The title compound, tetrasodium nonamanganese octadecaoxide, Na_4.32Mn₉O₁₈, was synthesized by reacting Mn₂O₃ with NaCl. One Mn atom occupies a site of 2/m symmetry, while all other atoms sit on mirror planes. The compound is isostructural with Na₄Ti₄Mn₅O₁₈ and suggestive of Mn³⁺/Mn⁴⁺ charge ordering. It has a double‐tunnel structure built up from double and triple chains of MnO₆ octahedra and single chains of MnO₅ square pyramids by corner sharing. Disordered Na⁺ cations occupy four crystallographic sites within the tunnels, including an unexpected new Na⁺ site discovered inside the large S‐shaped tunnel. A local‐ordering model is used to show the possible Na⁺ distribution, and the unit‐cell evolution during charging/discharging is explained on the basis of this local‐ordering model.     

Bismuth compounds [Ph3BuP]+I?, [Ph3BuP] 2+ [Bi2I8 · 2Me2C=O]2?, and [Ph3BuP] 2+ [Bi2I8 · 2Me2S=O]2?: Syntheses and crystal structures

The complexes [Ph₃BuP]₂⁺[Bi₂I₈ · 2Me₂C=O]²⁻ (II) and [Ph₃BuP]₂⁺[Bi₂I₈ · 2Me₂S=O]²⁻ (III) are synthesized by the reactions of triphenyl(n-butyl)phosphonium iodide (I) with bismuth iodide in acetone and dimethyl sulfoxide. In the cations of complexes I–III, the P atoms have a distorted tetrahedral coordination (CPC angles 106.3(2)°–112.0(3)°). The butyl group in cation I is disordered over two positions. In the binuclear centrosymmetric anions of structures II and III, the octahedrally coordinated bismuth atoms are linked in pairs by two bridging (br) iodine atoms (Bi-I_br 3.1508(7) and 3.2824(8) ? in compound II, 3.1961(3) and 3.3108(3) ? in complex III), which are coplanar to four terminal (t) iodine atoms (Bi-I_t 2.9260(7) and 2.9953(6) ? in complex II, 2.9206(3) and 2.9786(3) ? in complex III). The two remaining positions at the bismuth atom are occupied by the iodine atom (Bi-I_t 2.8531(7) ? in complex II, 2.8984(3) ? in complex III) and O atom of the organic molecule (Bi-O 2.747(6) ? in complex II, 2.507(3) ? in complex III). Original Russian Text ? V.V. Sharutin, I.V. Egorova, N.N. Klepikov, E.A. Boyarkina, O.K. Sharutina, 2009, published in Koordinatsionnaya Khimiya, 2009, Vol. 35, No. 3, pp. 188–192.