Journal of Chemical Crystallography最新文献

The adjoined 3d–4f metallacrown (MC) molecule Dy^III₂Mn^III₆(H₂shi)(Hshi)(shi)₇(py)₉·2py·0.7H₂O, 1, where H₃shi is salicylhydroxamic acid and py is pyridine, has been synthesized and characterized by FT–IR spectroscopy and single-crystal X-ray diffraction. The core of the molecule consists of two metallacrown (MC) rings, an archetypal 12-MC-4 and a collapsed 11-MC-4, that are linked through a common ring Dy^III center. For the 12-MC-4 portion of 1, the heterobimetallic composition of the MC ring with one Dy^III and three Mn^III ions is uncommon for metallacrowns as most 12-MC-4 rings are homometallic. In addition, the 12-MC-4 binds a Dy^III cation in the central cavity of the MC. The coordination environment about the central Dy^III ion has a triangular dodecahedron shape, which again is atypical. For 12-MC-4 molecules with a central lanthanide ion, the central lanthanide ion typically adopts a square antiprism geometry. The ring Dy^III cation of the 12-MC-4, which has a biaugmented trigonal prism shape, is shared with the collapsed 11-MC-4 and serves to join both metallacrowns. The collapsed 11-MC-4 ring is also composed of three Mn^III and one Dy^III ions. For one of the ring metal–metal linkages, only an oxygen atom is present, and an eleven membered ring is generated. In addition, the Dy^III center and one of the Mn^III centers bind to ring oxygen atoms on the opposite side of the MC ring; thus, the potential cavity of the MC is collapsed, and the MC does not bind a central metal ion as is customary.

Graphical Abstract

The preparation and characterization of two supramolecular complexes from octahedral [Ta₆Cl₁₂(CN)₆]^4−/3− units and 2, 2′: 6′, 2″-terpyridine (Terpy) metal complexes as building blocks are reported. Single crystal analyses revealed [Mn(Terpy)]₂[Ta₆Cl₁₂(CN)₆]·MeOH (1) features a neutral two-dimensional (2D) framework composed of layers based on [Ta₆Cl₁₂(CN)₆]⁴⁻ and [Mn(Terpy)]²⁺. Each layer is built of 6-connected [Ta₆Cl₁₂]²⁺ and 3-connected Mn(II) nodes bridged by cyanide ligands. The layers are held together by MeOH molecules. The layered structure is maintained after the removal of solvent molecule (MeOH) upon heating, leading to the formation of [Mn(Terpy]₂[Ta₆Cl₁₂(CN)₆] (1′). In the case of using Gd³⁺, the resultant product was revealed by single-crystal analyses to be an ionic compound [Gd(Terpy)(H₂O)₄(DMF)₂][Ta₆Cl₁₂(CN)₆]⋅DMF ⋅3H₂O (2). 2 has a three-dimensional (3D) framework built of [Gd(Terpy)(H₂O)₄(DMF)₂]³⁺ and [Ta₆Cl₁₂(CN)₆]³⁻ ions connected to each other via extensive hydrogen bonds and π-π interactions between the cations, anions, and solvent molecules. Thermal stabilities of 1‒2 are reported.

Graphical Abstract

The X-ray structures and thermal stabilities of a coordination polymer [Mn(Terpy)]₂[Ta₆Cl₁₂(CN)₆] ⋅MeOH and an ionic compound [Gd(Terpy)(H₂O)₄(DMF)₂][Ta₆Cl₁₂(CN)₆]⋅DMF⋅3H₂O are presented.

The crystal structures of di-μ-chlorobis[2-(5-methyl-pyridin-2-yl-κN)phenyl-κC(1)] diplatinum(II) (1) and chloro(N,N-dimethylformamide-κO)[2-(5-methyl-pyridin-2-yl-κN)phenyl-κC(1)]platinum(II) (2) have been determined by means of the X-ray diffraction. Both complexes cocrystallize in the monoclinic space group C2/c with a = 39.5457(18) Å, b = 7.2482(4) Å, c = 21.2269(10) Å and β = 121.460(2)°. The asymmetric unit consists of half a centrosymmetric compound (complex 1) and one full independent compound (complex 2).

Graphical Abstract

The X-ray structures of co-crystallized di-μ-chlorobis[2-(5-methyl-pyridin-2-yl-κN)phenyl-κC(1)]diplatinum(II) (1) as starting material and of the derivative chloro(N,N-dimethylformamide-κO)[2-(5-methyl-pyridin-2-yl-κN)phenyl-κC(1)]platinum(II) (2) are reported.

A terbium 2,6-naphthalenedisulfonic acid compound, [Tb(H₂O)₉]Cl(C₁₀H₆O₄S₄)₂ (C₁₀H₆O₄S₄²⁻ = 2,6-naphthalenedisulfonate), is prepared and characterized by single-crystal X-ray diffraction. This compound is characterized by an isolated structure with the terbium ion possessing a mono-capped square antiprism coordination geometry. The [Tb(H₂O)₉]³⁺ cations and (2,6-naphthalenedisulfonic acid)²⁻ anions are linked by hydrogen-bonding interactions to yield a three-dimensional supramolecular network. The solid state luminescence spectrum reveals that this compound shows the strongest emission band in the red region. The luminescence emission peaks can be ascribed to the characteristic emissions of the 4f electron intrashell transitions ⁵D₄ → ⁷F₅, ⁵D₄ → ⁷F₄ and ⁵D₄ → ⁷F₂ of the Tb³⁺ ion. The CIE (Commission Internationale de L’Eclairage) chromaticity coordinates are (0.5647, 0.4338). Solid-state UV/Vis diffuse reflectance spectra reveal that compound 1 shows a wide optical band gap of 4.92 eV.

Graphical abstract

A novel terbium 2,6-naphthalenedisulfonic acid compound is prepared and characterized

Three new cyanide-bridged heterobimetallic complexes {[Cu(L)]₂[Cr(CN)₅(NO)]}ClO₄·2H₂O (1), {{[Cu(cyclam)][Fe(CN)₅(NO)]}·H₂O}_n (2), {{[Cu(cyclam)]₃[Cr(CN)₅(NO)]₂}·CH₃OH·4H₂O}_n (3) (L=2,12-dimethyl-3,7,11,17-tetraazabicyclo [11.3.1] heptadeca-1 (17), 13, 15-triene, cyclam=1,4,8,11-tetraazacyclodecane) have been successfully assembled from the pentacyanometalates and two copper(II) compounds and characterized by elemental analysis, IR spectroscopy and X-ray structure determination. X-ray structural analysis revealed that the Complex 1 is a cationic trinuclear CrCu₂ entity with the positive charge balanced by ClO₄⁻ ion, while complexes 2 and 3 were structurally characterized showing a 1D chain. The magnetic properties of the reported cyanide-bridged complexes have been experimentally studied and theoretically simulated, disclosing the ferromagnetic interaction between the Cr(I) ion and the Cu(II) ion through the cyanide bridge.

Graphical Abstract

The crystal structure of the thiosemicarbazide derivative 4-cyclohexyl-1-(thiophene-2-carbonyl)thiosemicarbazide (ChtcTSC), C₁₂H₁₇N₃OS₂, is reported here. The title compound ChtcTSC has been characterized by various physicochemical techniques viz UV–Vis., Infrared, and NMR. It crystallizes in the monoclinic system having space group P2₁/c. The dihedral angle between the thiophene and cyclohexyl rings is 60.7(4)^°. The crystal packing is established by intermolecular N–H⋯O packing interactions involving a three-center donor hydrogen bond between the keto oxygen atom of the thiophene group and H atoms belonging to the hydrazine group which links the molecules into chains along the (011) plane of the unit cell. Hydrogen bonds between the hydrazine hydrogen atom and one of the thiophene groups and C–H⋯Cg π -ring interactions provide added stability to the crystal packing. The fingerprint plots associated with Hirshfeld surface analysis indicate that there are different types of weak interactions viz. O⋯H–C, O⋯H–N, and S⋯H–C. The geometry optimization has been performed using the DFT method, and geometrical parameters thus obtained for ChtcTSC correlate with the single-crystal X-ray data. The TD-DFT study showed a small HOMO and LUMO energy gap of 2.869 eV. The electronic transition from the ground state to the excited state due to a transfer of electrons from HOMO to LUMO levels is mainly associated with the n → π* transition.

Graphical Abstract

The crystal structure of 4-cyclohexyl-1-(thiophene-2-carbonyl)thiosemicarbazide (ChtcTSC) is reported here where the title compound ChtcTSC has been characterized by various physiochemical techniques including UV–Vis., Infrared, NMR, DFT and Hirshfeld surface analysis.

Two new hybrid solids viz. {Hpz}₂[H₇CrMo₆O₂₄]·6H₂O (1) and [Co(2-Hampz)₂Cl₄] (2) have been crystallized via solvent evaporation technique using pyrazole (pz) and 2-aminopyrazine (2-ampz) respectively. The solids were characterized using single crystal X-ray diffraction, fourier transform infrared spectroscopy, elemental analysis, scanning electron microscopy and thermal analysis. The solid 1 crystallized in orthorhombic system with space group Pbca, a = 23.1796(8), b = 11.1281(4), c = 25.1499(9) Å, Z = 8. The solid 2 crystallized in triclinic system with space group P-1, a = 7.1986(5), b = 7.3917(5), c = 7.8896(6) Å, α = 115.758(3), β = 110.450(3), γ = 96.904(3)°, Z = 1. While, solid 1 is a new Anderson–Evans cluster based solid, 2 is a new pseudopolymorph of cobalt complex [Co(2-ampz)₄Cl₂]. Crystal structure analysis suggested that supramolecular interactions facilitate the crystal packing in solids 1 and 2. In addition, the role of synthetic parameters in dictating the nature of self-assembly of solids 1 and 2 in aqueous medium has also been analyzed.

Graphical Abstract

An Anderson–Evans cluster based solid, {Hpz}₂[H₇CrMo₆O₂₄]·6H₂O (1) and a new pseudopolymorph of cobalt complex [Co(2-ampz)₄Cl₂] viz. [Co(2-Hampz)₂Cl₄] (2) have been synthesized using pyrazole (pz) and 2-aminopyrazine (2-ampz) respectively.

The crystal structure of NH₄[Zn(cma)(H₂O)₂]·H₂O (cma^3– = N-carboxymethylaspartate(3–)) is determined by single crystal X-ray structure analysis. The orthorombic crystals (P2₁2₁2₁, a = 7.7901(4) Å, b = 11.2368(4) Å, c = 13.2048(5) Å, α = β = γ = 90°, Z = 4) were obtained from the reaction mixture in the form of racemic conglomerate. The single crystal X-ray structure analysis revealed the maximum deviation of bond angles around the Zn atom from an ideal octahedral geometry 14.09° with ∑ = 67.23° and Θ = 236.69°. Intermolecular interactions are based mainly on a moderate N–H⋯O and O–H⋯O hydrogen bonds. The structure shares similar structural features with other structures containing aspartates and their derivatives as a ligands. The results of using different HAR methods based on semi-empirical (B3LYP) and non-empirical (PBE0) global hybrid GGA DFT functionals were compared.

Graphical Abstract

The crystal structure of NH₄[Zn(cma)(H₂O)₂]·H₂O (cma^3– = N-carboxymethylaspartate(3–)) is determined by single crystal X-ray structure analysis. The orthorombic crystals (P2₁2₁2₁, a = 7.7901(4) Å, b = 11.2368(4) Å, c = 13.2048(5) Å, α = β = γ = 90°, Z = 4) were obtained from the reaction mixture in the form of racemic conglomerate.

Abnormal carbene complex of Pd(L1)₂, where L1 = 1,3-Bis(2,6-diisopropylphenyl)-2,4-diphenylimidazole and normal carbene complex of Pd(L2)₂, where L2 = 1,3-dimesityl-4,9-dioxonaphtho-2,3-diimidazole were prepared from a Pd(0) precursor Pd(COD)(CH₂TMS)₂. Both the complexes crystalize in the triclinic space group P-1 and cell parameters of Pd(L1)₂ and Pd(L2)₂ are a = 12.0477 Å, b = 17.5269 Å, c = 18.9786 Å, α = 114.4855°, β = 92.5295°, γ = 107.9472° and a = 11.5007 Å, b = 15.2316 Å, c = 17.9007 Å, α = 67.061°, β = 72.143°, γ = 72.183° respectively. In both case N-heterocyclic ligands are distorted towards palladium direction. Further, crystal structures reveal that the palladium atom is covalently bonded to the two aNHC and nNHC ligands respectively. The electrochemical properties of these complexes were determined by cyclic voltammetry analysis in THF solution under argon atmosphere. The enunciated reversibility of the complexes can be explained by sequential one electron oxidations of the palladium centre from Pd(0) to Pd(I) and then Pd(II).

Graphical Abstract

Abnormal carbene complex of Pd(L1)₂, where L1 = 1,3-Bis(2,6-diisopropylphenyl)-2,4-diphenylimidazole and normal carbene complex of Pd(L2)₂, where L2 = 1,3-dimesityl-4,9-dioxonaphtho-2,3-diimidazole were prepared from a Pd(0) precursor of Pd(COD)(CH₂TMS)₂. The crystal structures were determined by single crystal X-ray diffraction data and electrochemical properties were also determined by cyclic voltammetric analysis.