Synthesis and crystal structure of [(C<Subscript>7</Subscript>H<Subscript>10</Subscript>N)<Subscript>2</Subscript>]<Superscript>2+</Superscript> [Sb<Subscript>2</Subscript>Cl<Subscript>8</Subscript>]<Superscript>2−1</Superscript>

The reaction of 2,6-dimethylpyridine with SbCl₃ and HCl affords the title compound, the structure of which is ascertained by X-ray diffraction. The unit cell consists of one bridged Sb₂Cl₈²⁻ anion and two 2,6-dimethylpyridinium cations. The trivalent antimony ion is bonded not only directly to chlorine anions, but also is coordinated with chlorine anions by secondary bonds. In the crystal, there exists infinite coordinated chains of [Sb₂Cl₈] _n ²ⁿ⁻ anions running along the a axis, which link 2,6-dimethylpyridinium cations by N-H…Cl hydrogen bonds.     

Self-Assembly of a New 1D Coordination Polymer Built of [Nb<Subscript>6</Subscript>Cl<Subscript>12</Subscript>(CN)<Subscript>6</Subscript>]<Superscript>4−</Superscript> and Mn(III) Complexes

Abstract  

A new 1D coordination polymer [Me₄N]₃{[Mn(L)][Nb₆Cl₁₂(CN)₆]}·3MeCN·H₂O (1) (L = acacen ²⁻ = N,N′-bis(acetylacetone)-1,2-ethylenediimine) was synthesized from reaction between [Me₄N]₄[Nb₆Cl₁₂(CN)₆] and [Mn(L)]Cl in acetonitrile. The crystal structure of 1 was determined from single-crystal X-ray diffraction analysis. Compound 1 crystallizes in the tetragonal system, space group I4₁/a (No. 88), a = 30.585(4), c = 27.348(6) ?, V = 25582(7) ?³, Z = 16. Its 1D framework consists of chains formed of metal clusters and Mn(L) complexes linked to each other by Nb–C≡N–Mn–N≡C–Nb linkages. The chains extend along the a and b crystallographic axes and are related to each other by 4₁ screw axis. The chains are held together by [Me₄N]⁺ cations and solvent molecules located in channels running between the chains. 1 and the previously reported 1D coordination polymer [Me₄N]₃{[Mn(5-MeO-salen)][Nb₆Cl₁₂(CN)₆]} (3) differ from each other in terms of their synthesis and their structural characteristics.     

Unique coordination in metal nitroprussides: The structure of Cu[Fe(CN)<Subscript>5</Subscript>NO]⋅2H<Subscript>2</Subscript>O and Cu[Fe(CN)<Subscript>5</Subscript>NO]

The structures of copper pentacyanonitrosylferrate dihydrate, Cu[Fe(CN)₅NO]2H₂O, and anhydrous, Cu[Fe(CN)₅NO], have been determined from their XRD powder patterns and refined using the Rietveld method. The dihydrate structure was solved by direct methods and the anhydrous one was elucidated by chemical intuition. Cu[Fe(CN)₅NO]2H₂O is orthorhombic, space group Amm2 (38) and Z = 2. In this structure the iron is coordinated to five CN and a NO ligand, while the copper atom is coordinated, in a unique fashion, to four equatorial CN groups at N ends and two water molecules. Cu[Fe(CN)₅NO] is tetragonal, space group I4 mm (107) and Z = 2. This structure is obtained from the dehydration of the orthorhombic one; reordering allows the Cu atom to coordinate not only to the four equatorial cyanides but also to the axial cyanide. The coordination of the iron atom remains as in the orthorhombic structure. Agreement factor obtained from the final refinement were as follows: R_wp = 5.10 and R_B = 4.57 for the orthorhombic structure and R_wp = 6.52 and R_B = 7.82 for the tetragonal one. These crystal structures are also supported by IR and Mössbauer spectroscopic data and thermogravimetry.     

Solvothermal Syntheses and Crystal Structures of Two Thiostannates(IV) [M(tepa)]<Subscript>2</Subscript>(<Emphasis Type="Italic">μ</Emphasis>-Sn<Subscript>2</Subscript>S<Subscript>6</Subscript>) (M = Fe<Superscript>2+</Superscript> and Co<Superscript>2+</Superscript>)

Abstract  

Two new thiostannates [M(tepa)]₂(μ-Sn₂S₆) (tepa = tetraethylenepentamine, M = Fe²⁺ 1 and Co²⁺ 2) were prepared by solvothermal method. Compounds 1 and 2 are isostructural. Both the compounds crystallize in the tetragonal system, space group I41/a (no. 88) with the crystal parameters of 1: a = 25.683(2) ?, b = 25.683(2) ?, c = 9.9860(9) ?, V = 6,586.7(11) ?³, Z = 8, and 2: a = 25.742(3) ?, b = 25.742(3) ?, c = 9.8977(12) ?, V = 6,558.5(14) ?³, Z = 8. The Sn₂S₆ ⁴⁻ anion acts as a bidentate bridging ligand connecting two transition metal complex cations by trans terminal S atoms to form neutral centrosymmetric [M(tepa)]₂(μ-Sn₂S₆) moieties.     

Synthesis and Structural Characterization of [Ag(H-dpa) (η<Superscript>2</Superscript>-styrene)]BF<Subscript>4</Subscript>: Comparing Silver and Copper for Olefin Binding

Abstract  

The molecular structure of the complex bis-(2-pyridyl)amine(η²-styrene)silver(I) tetrafluoroborate has been determined. The geometry about the Ag⁺ ion is pseudo-trigonal planar, with coordination sites occupied by the two pyridyl nitrogen atoms and the midpoint of the alkene double bond. Crystal packing of the molecule is influenced by hydrogen bonding of the amine with the tetrafluoroborate anion, in addition to intermolecular Ag⁺···aromatic contacts. ¹H NMR confirms crystallographic data that suggest weak metal to olefin π-backbonding. Crystal data: space group P2₁/n, a = 12.764(3), b = 10.590(2), c = 13.624(3) Å, β = 91.17(3)°, V = 1841.3(7) Å³, Z = 4, R = 0.0453, wR ₂ = 0.1098.     

One Novel Three-dimensional Network Constructed from [Mn(4,4′-bip)<Subscript>2</Subscript>(OH<Subscript>2</Subscript>)<Subscript>4</Subscript>]<Superscript>2+</Superscript> Cations and DBA<Superscript>2−</Superscript> Anions via Hydrogen-bonding and π–π Interactions

Abstract One new mononuclear manganese complex of [Mn(4,4′-bip)₂(OH₂)₄](DBA) · 4H₂O (1) (4,4′-bipyridine, 4,4′-bip; H₂DBA, benzene-1,3-dicarboxylic acid) has been obtained from the hydrothermal reaction of MnCl₂ · 4H₂O, 4,4′-bipyridine and H₂DBA in the solvent of H₂O at 140 °C for 3 days, characterized by X-ray analysis, spectroscopic methods, and thermal analysis. Packing diagram shows that the three-dimensional network was formed via hydrogen bonds and strong π–π interactions. Graphical abstract One Novel Three-dimensional Network Constructed from [Mn(4,4′-bip) ₂ (OH ₂ ) ₄ ] ²⁺ Cations and DBA ²⁻ Anions via Hydrogen-bonding and π–π Interactions Ying Liu, Bao Zhang, Jian-min Dou, Da-qi Wang, Da-cheng Li, Lei Zhou One new mononuclear manganese complex of [Mn(4,4’-bip)₂(OH₂)₄](DBA) · 4H₂O (1) (4,4’-bipyridine, 4,4’-bip; H₂DBA, benzene-1, 3-dicarboxylic acid) has been obtained and haracterized by X-ray analysis, spectroscopic methods, and thermal analysis. Packing diagram shows that the three-dimensional network was formed via hydrogen bonds and strong π-π interactions.      

Aquanitrilotris(methylenephosphonato)dirubidium [Rb<Subscript>2</Subscript>(H<Subscript>2</Subscript>O){μ<Superscript>12</Superscript>-NH(CH<Subscript>2</Subscript>PO<Subscript>3</Subscript>H)<Subscript>3</Subscript>}]: Synthesis and structure

Aquanitrilotris(methylenephosphonato)dirubidium is a 3D coordination polymer with a layer structure. Space group \(P\bar 1\), Z = 2; a = 8.0380(3) Å, b = 9.0522(4) Å, and c = 10.7837(4) Å; α = 113.252(4)°, β = 105.391(3)°, and γ = 96.182(3)°. Rb atoms populate two symmetrically inequivalent positions with c.n. = 8 and 10; significant difference in O–Rb–O angles in the coordination polyhedra is indicative of the ionic type of Rb–O bonds. In the crystal packing, molecules are connected by not only coordination bonds but hydrogen bonds as well.     

Molecular structure of [(<Superscript>t</Superscript>Bu)<Subscript>2</Subscript>Al(μ-OC<Subscript>6</Subscript>H<Subscript>4</Subscript>-2-Me)]<Subscript>2</Subscript>

The molecular structure of [(^tBu)₂Al(-OC₆H₅-2-Me)]₂ has been determined. Both the ortho-tolyl methyl groups are oriented towards Al(2). The intramolecular steric interaction between the ortho-methyl groups and the tert-butyl ligands results in the geometry about the bridging oxygen being significantly distorted while the geometries about the aluminum centers show a distortion from tetrahedral that is less than the sterically less hindered [(^tBu)₂Al(-OPh)]₂. Crystal data: group C2/c, a = 13.733(3) Å, b = 15.135(3) Å, c = 15.420(3) Å, = 104.24(3), V = 3106(1) ų, Z = 4, R = 0. 0612, wR₂ = 0.1787.     

Crystal structure of Sr(AsUO<Superscript>6</Superscript>)<Subscript>2</Subscript> · 8H<Subscript>2</Subscript>O

The crystal structure of the compound Sr(AsUO₆)₂ · 8H₂O is determined by X-ray diffraction analysis (monoclinic system, sp. gr. Pc, unit-cell parameters a = 7.154(1) Å, b = 7.101(1) Å, c = 18.901(7) Å, β = 92.67(2)°, Z = 2). The structure is built by (001)-parallel [AsUO₆]^? layers formed by flattened square UO₆ bipyramids and AsO₄ tetrahedra. The neighboring layers are connected via SrO₈ square antiprisms. The cavities of the polyhedral framework thus formed are occupied by H₂O molecules. The displacements of the anion complexes by a half-translation with respect to one another along only one lattice period is a characteristic feature of this polymorphous modification of the uran-mica group.     

Base-Stabilized Monomeric Stibinoalane dmap–Al(Et<Subscript>2</Subscript>)Sb(<Superscript>t</Superscript>Bu)<Subscript>2</Subscript>

Abstract  

The six-membered heterocycle [Me₂AlSb(t-Bu)₂]₃ was reacted with the strong Lewis-base 4-dimethylaminopyridine (dmap), yielding the first completely alkyl-substituted monomeric complex dmap–Al(Me₂)Sb(t-Bu)₂ 1. 1 was characterized by NMR spectroscopy and single crystal X-ray diffraction. 1 is monoclinic, space group P2 ₁ /n with a = 9.9004(2) ?, b = 16.8166(3) ?, c = 13.8400(3) ?, β = 100.746(1)° and Z = 4.     

Synthesis and Crystal Structure of a New Ion-Pair Complex Based on [Ni(tdas)<Subscript>2</Subscript>]<Superscript>2−</Superscript> Anion and Triphenylphosphinium Cation

Abstract  A new ion-pair complex, bis(1-benzyltriphenylphosphinium) bis(1,2,5-thiadiazole-3,4-dithiolato)nickelate(II), [BzTPP]₂[Ni(tdas)₂](1), has been prepared and characterized by elemental analyses, UV, IR, MS spectrum, molar conductivity and single crystal X-ray diffraction. The title complex crystallizes in the triclinic space group P-1, a = 9.098(1) Å, b = 9.666(1) Å, c = 29.573(3) Å, α = 83.81(1)°, β = 81.97(1)°, γ = 78.83(1)°, V = 2,517.5(4) ų, Z = 2. The unit cell contains two [BzTPP]⁺ and two halves of [Ni(tdas)₂]²⁻ anions in which the anion exhibits a quasi-planar structure. The [BzTPP]⁺ cation adopts a conformation where four phenyl rings are twisted to the C–C–P reference plane. The weak cation–cation C–H···π, π···π interactions and anion–cation C–H···N hydrogen bonds between the anion and cation play an important role in the stacking and stabilizing of the title complex. Graphical Abstract  The title new ion-pair complex, bis(1-benzyltriphenylphosphinium) bis(1,2,5-thiadiazole-3,4-dithiolato)nickelate(II), [BzTPP]₂[Ni(tdas)₂](1), contains two [BzTPP]⁺ and two halves of [Ni(tdas)₂]²⁻ anions in which the weak cation–cation C–H···π, π···π interactions and anion−cation C–H···N hydrogen bonds between the anion and cation play an important role in the stacking and stabilizing of the title complex.      

Crystal and molecular structure of an ion-pair complex based on [Ni(mnt)<Subscript>2</Subscript>]<Superscript>2−</Superscript> anion and imidazolium derivative cations

A new ion-pair complex, 1-methyl-3-benzylimidazolium bis(maleonitrile-dithiolato) nickelate(II), has been synthesized and characterized by IR spectroscopy, UV-visible spectroscopy and X-ray crystallography. The crystallographic data for the complex: triclinic , a = 8.415(1) Å, b = 9.924(1) Å, c = 11.333(2) Å, = 114.11(1), = 102.46(1), = 100.88(1), V = 801.8(2) ų, Z = 1. The molecular packing pattern showed a completely separated column stacking for cations and anions of the complex along with the b-axis. The anion is not completely planar. The five-membered nickel-containing rings are slightly puckered. The cation, [BzIm]⁺, adopts a conformation where the benzene ring and imidazole ring twisted with the reference plane C10–C11–N3.     

Crystal Structure and Characterization of [Ni(RPOEt)<Subscript>2</Subscript>(C<Subscript>2</Subscript>H<Subscript>5</Subscript>OH)<Subscript>2</Subscript>](ClO<Subscript>4</Subscript>)<Subscript>2</Subscript> [RPOEt = bis{(diphenylphosphinyl)methyl}ethyl phosphinate]

Abstract  

The compound [Ni(RPOEt)₂(C₂H₅OH)₂](ClO₄)₂ (1) [RPOEt = bis{(diphenylphosphinyl)methyl}ethyl phosphinate] has been prepared in the form of single crystals and characterized by elemental and thermal analyses, IR spectroscopy and by a single crystal X-ray diffraction study. The complex crystallizes in the triclinic P[`1] P\bar{1} space group with a = 9.8773(5), b = 13.741(1), c = 14.287(1) ?, α = 64.313(9), β = 70.280(5), γ = 89.973(7)o, V = 1620.5(2) ?³, and Z = 1. The nickel(II) atom in 1, situated at the centre of symmetry, is coordinated by four oxygen atoms from two RPOEt ligands and two oxygen atoms from two ethanol molecules in a slightly distorted octahedral environment. The third phosphoryl-oxygen atom from the phosphinate ligand is hydrogen bonded to the oxygen atom of the ethanol molecule coordinated to nickel(II). The complex [Ni(RPOEt)₂(C₂H₅OH)₂]²⁺ cations are linked by the C–H···O hydrogen bonds into one-dimensional chains and by the composite π···π and C–H···π phenyl interactions into a final three-dimensional structure.     

Synthesis and X-ray diffraction study of [UO<Subscript>2</Subscript>(NO<Subscript>3</Subscript>)<Subscript>2</Subscript>(H<Subscript>2</Subscript>O)<Subscript>2</Subscript>] · 2C<Subscript>12</Subscript>H<Subscript>18</Subscript>O

The compound [UO₂(NO₃)₂(H₂O)₂] · 2C₁₂H₁₈O was synthesized and studied by IR spectroscopy and X-ray diffraction. The structure consists of the neutral island groups [UO₂(NO₃)₂(H₂O)₂], which belong to the crystal-chemical group AB ⁰¹ ₂ M ¹ ₂ (A = UO₂ ²⁺, B ⁰¹ = NO₃⁻, M ¹ = H₂O) of uranyl complexes, and 1-adamantyl methyl ketone molecules. The characteristic features of the association of the complexes [UO₂(NO₃)₂(H₂O)₂] and 1-adamantyl methyl ketone molecules in the crystal structure via hydrogen bonds are considered with the use of Voronoi-Dirichlet polyhedra.     

Synthesis and Characterization of <Emphasis Type="Italic">Cis</Emphasis>-[V<Superscript>IV</Superscript>O(pzc)<Subscript>2</Subscript>(H<Subscript>2</Subscript>O)]·2H<Subscript>2</Subscript>O (pzc: 2-pyrazinecarboxylate)

Abstract  

Hydrothermal synthesis and the structural characterization of V(IV) complex of 2-pyrazinecarboxylate (pzc), is reported. The vanadium is in a distorted octahedral environment. Pairs of pyrazine-2-carboxylate ligands are always cis to each other. The pzc ligands do not link adjacent vanadium atom directly. The remainder of the three-dimensional network is completed by intense hydrogen bonding of uncoordinated water molecules to aqua and pzc ligands. Cis-[V^IVO(pzc)₂(H₂O)]·2H₂O, 1, was characterized by means of elemental analysis (CHNS), TGA, FT-IR, manganometric titration, bond valance sum calculations and single crystal X-ray diffraction methods. Crystal data for 1: monoclinic space group P2 ₁ /c and unit-cell parameters are a = 9.1142(5), b = 16.5822(10), c = 12.8936(7) ?, β = 131.625(3)° and Z = 4. To the best of our knowledge, cis-[V^IVO(pzc)₂(H₂O)] is reported without single crystal structure by Eugenio Garribba and his colleagues in year 2006. Herein we complete full characterization of the title complex with single crystal structure and also 1 will be the first reported example of solid vanadium complex of 2-pyrazinecarboxylates involving intense hydrogen bonding.     

Synthesis and Crystal Structures of Three Pyrazine-2-carboxylate Containing Isostructural Complexes: M(2-pyrazine-carboxylate)<Subscript>3</Subscript> (M = Co<Superscript>+3</Superscript>, Cr<Superscript>+3</Superscript>, and Rh<Superscript>+3</Superscript>)

Abstract Three new isostructural coordination complexes, M(pca)₃, where M = Co (1), Cr (2), or Rh (3) and 2-pyrazine-carboxylate (pca), have been synthesized solvothermally and characterized by single crystal X-ray diffraction and powder X-ray diffraction. In structures 1-3, the pca ligand chelates to the metal centers in a tris-chelating arrangement through proximal nitrogen and oxygen donor atoms. Structures 1-3 are monoclinic and crystallize in the space group C2/C. In structure 1, a = 28.066(13) ?, b = 8.036(4) ?, c = 13.577(6) ?, and β = 90.2(10)°. In structure 2 a = 28.318(3) ?, b = 8.089(4) ?, c = 13.792(12) ?, and β = 90.256(2)°. In structure 3, a = 28.679(4) ?, b = 8.051(13) ?, c=13.847(2) ?, and β = 90.585(2)°. Graphical Abstract Three new isostructural coordination complexes, M(pca)₃, where M = Co, Cr, or Rh and 2-pyrazine-carboxylate (pca), have been synthesized solvothermally and characterized by single crystal X-ray diffraction and powder X-ray diffraction.      

Optical and nonlinear laser properties of the χ<Superscript>(3)</Superscript>-active monoclinic α-KY(WO<Subscript>4</Subscript>)<Subscript>2</Subscript> crystals

Monoclinic α-KRE(WO₄)₂ crystals are grown. Their structure is described in two crystallographic settings. The principal refractive indices are determined and the coefficients and characteristic wavelengths are used for calculating refractive indices by the Selmeyer formulas. The data on the anisotropic parametric Raman generation in these crystals under the picosecond pumping are discussed.     

Anisotropy of microhardness and fracture of (NH<Subscript>4</Subscript>)<Subscript>2</Subscript>Ni(SO<Subscript>4</Subscript>)<Subscript>2</Subscript> · 6H<Subscript>2</Subscript>O (ANSH) crystals

The Vickers hardness of the (010) and (001) planes in (NH₄)₂Ni(SO₄)₂ · 6H₂O (ANSH) crystals has been measured. Anisotropy hardness of the first kind is revealed for the (010) plane in ANSH. The hardness anisotropy coefficient k ₂ was determined to be 1.5. The temperature dependence of the microhardness of the (001) face of ANSH crystals was investigated in the temperature range from 20 to 80°C. The character of fracture of the (100), (010), and (001) planes during indentation with a spherical indenter has been qualitatively determined.     

Optical properties and refractive indices of Gd<Subscript>3</Subscript>Al<Subscript>2</Subscript>Ga<Subscript>3</Subscript>O<Subscript>12</Subscript>:Се<Superscript>3+</Superscript> crystals

Crystals of cerium-doped gadolinium–gallium–aluminum garnet have been grown by the Czochralski method. The transmission and reflection spectra of these crystals in the wavelength range of 250–800 nm have been obtained by optical spectroscopy. Refractive indices are calculated based on the measured Brewster angles, the experimental results are approximated using the Cauchy equation, and a dispersion dependence is obtained.     

Nitrilotris(methylenephosphonato)potassium K[μ<Superscript>6</Superscript>-NH(CH<Subscript>2</Subscript>PO<Subscript>3</Subscript>)<Subscript>3</Subscript>H<Subscript>4</Subscript>]: Synthesis,structure, and the nature of the K–O chemical bond

The crystal structure of nitrilotris(methylenephosphonato)potassium K[μ⁶-NH(CH₂PO₃)₃H₄]—a three-dimensional coordination polymer—was determined. The potassium atom is coordinated by seven oxygen atoms belonging to the six nearest ligand molecules, resulting in distorted monocapped octahedral coordination geometry. The complex contains the four-membered chelate ring K–O–P–O. The K–O chemical bond is predominantly ionic. Meanwhile, the bonds of the potassium atom with some oxygen atoms have a noticeable covalent component. In addition to coordination bonds, the molecules in the crystal packing are linked by hydrogen bonds.