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2015 year, number 8
T. N. Grishaeva1, A. N. Maslii1, V. V. Bakovets2, A. M. Kuznetsov1
1Kazan National Research Technological University, Kazan, Russia 2Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
Keywords: теория функционала плотности, РСМ, функционал PBE, комплекс гость-хозяин, диметилглиоксимат, никель(II), кукурбит[8]урил, супрамолекулярные соединения, density functional theory, РСМ, PBE functional, guest-host complex, dimethylglyoxymate, nickel(II), cucurbit[8]uril, supramolecular compounds
Abstract >>
Within density functional theory the structure of an inclusion compound based on Ni(II) dimethylglyoxymate and the macrocyclic cucurbit[8]uril nanocavitand is investigated and the thermodynamic parameters of its formation are estimated. Based on the results obtained a prediction is made about the principal possibility of the synthesis of this inclusion compound.
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R. Ghiasi, E. Amini
Islamic Azad University, Qiam Dasht, Tehran, Iran
Keywords: iridapyridine, frontier orbital analysis, natural bond orbital (NBO) analysis, N NQR parameters
, nucleus independent chemical shift (NICS)
Abstract >>
Using quantum chemical calculations, we report structures, energetics, natural bond analysis, aromaticity and 14N NQR parameters of the irdidapyridine isomers. The mpw1pw91, PBEPBE and PBE1PBE calculations indicate the most stability for meta-isomer. Global electrophilicity index shows that iridapyridines are stronger electrophile rather than pyridine. Local reactivity descriptors as Fukui functions, local softnesses and electrophilicity indices analyses are performed to find out the reactive sites within molecules. Nucleus-independent chemical shift (NICS) has been evaluated to understand the aromaticity. Also, changes in 14N NQR parameters of the molecules are studied.
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Q.Y. Xia1,2, D.X. Ma2, D.J. Li2, B.H. Li2, X.Q. Wang2, G.F. Ji1
1Institute of Fluid Physics, Chinese Academy of Engineering Physics, Mianyang, P. R. China 2Linyi University, Linyi, P. R. China
Keywords: asymmetric clusters, density functional theory (DFT), structures, IR spectra, stabilities
Abstract >>
The structures and properties of asymmetric heterocycles (HBrBN3)n (n = 1-4) are systematically studied at the B3LYP/6-31G* level. The molecules (HBrBN3) n (n = 2-4) have the core structures of a 2n-membered ring with alternating boron and a-nitrogen atoms. The relationships between geometrical parameters and oligomerization degree n are discussed. The calculated IR spectra have four main characteristic regions. Trends in thermodynamic properties with temperature and oligomerization degree n are discussed. Thermodynamic analysis of the gas-phase oligomerizations shows that formation of the most stable heterocycles (HBrBN3)n (n = 2-4) is enthalpy driven in the range of 200-800 K.
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M.Z. Fashami, R. Ghiasi, Hoda Pasdar
Islamic Azad University, Kerman, Tehran, Iran
Keywords: [Cr(CO)py] complexes, substituent effect, solvent effect, N NQR parameters
Abstract >>
The structure, 14N NQR parameters, electronic spectra, and hyperplarizability of [Cr(CO)5py] in seven different solvents were theoretically computed with MPW1PW91 method based on Polarizable Continuum Model (PCM). The substituent effects in para- substituted Cr(CO)5-pyridine complexes have been evaluated. The results indicate that both polarity of solvents and the substituents have played a significant role on the structures and properties of complexes. The study also shows that the structural and solvent modification change the NLO properties.
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R. Ghiasi, E. Amini
Islamic Azad University, Qiam Dasht, Tehran, Iran
Keywords: iridabenzene, substituent effect, solvent effect, natural bond orbital (NBO) analysis, nucleus independent chemical shift (NICS), hyperpolarizability
Abstract >>
Using MPW1PW91 quantum chemical calculations, we report structures, frontier orbital analysis, natural bond analysis, and aromaticity of the C5H5Ir(PH3)3 iridabenzene and XC5H4Ir(PH3)3para-substituted iridabenzenes. The substituent effects were estimated from the donor-acceptor interaction energies of the natural bond orbitals of substituent and iridabenzene frame. Nucleus-independent chemical shift (NICS) has been evaluated to understand the aromaticity. Time dependent density functional theory (TD-DFT) is used to calculate the energy, oscillatory strength and wavelength absorption maxima (lmax) of electronic transitions and their nature. Changes in hyperpolarizability of molecules are studied. Influence of solvent on the structure, frontier orbital energies, λmax, and hyperpolarizability of C5H5Ir(PH3)3 iridabenzene has been studied.
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M. Lemmouchi1, D. Hannachi1,2, N. Ouddai1
1Universite El-Hadj Lakhdar, Batna, Algeria 2University Farhat Abbasse, Setif, Algeria
Keywords: triflate, lanthanide, actinide, coordination, intramolecular rearrangement
Abstract >>
Theoretical studies on the lanthanide and actinide triflate complexes M(OTf) n where M = La, Ce, Gd, Yb, Lu, Th, U, Np, Pu, Am, Cm, Bk, and No; n = 3 and 4, are carried out using functional density theory (DFT). The study of An(OTf)3 complexes showed that the three OTf groups are bidentate, generating a trigonal prism (TP). Two limiting structures of TP are observed; the most distorted is the thorium triflate Th(OTf)3 and the ideal one is U(OTf)3. The highest population contribution of 5 d orbital compared to 5 f orbital in Th-O bond of Th(OTf)3 explains the distortion. The intramolecular rearrangement of the OTf ligands in Ln(OTf)3 generates two conformers. In Yb(OTf)3, the pseudo-eclipsed and the staggered conformations are stable and can be isolated.
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A. Lashgari1, S. Ghammamy1, R. Ramirez-Tagle2, G. Salgado-Moran3
1Imam Khomeini International University, Qazvin, Iran 2Universidad Bernardo OВўHiggins, Santiago, Chile 3Universidad Andres Bello, Concepcion, Chile
Keywords: synthesis, halo compounds, main group elements, computation, spectroscopic studies
Abstract >>
Two new compounds of fluorine: (C2H5)4N[I2F] and (C2H5)4N[Br2F] have been easily synthesized in a nearly quantitative by a direct reaction of (C2H5)4NF, I2 and Br2. The products were isolated and characterized by elemental analysis and spectroscopic methods such as: Fourier transform infrared spectroscopy (FTIR) and ultraviolet-visible spectroscopy (UV-Vis). These compounds have been studied with the Scalar ZORA relativistic level of theory using the ADF program package. The molecular parameters, and vibrational spectra were calculated. The excitation energies were found by time-dependent perturbation density functional theory (TD-DFT). Molecule optimization, frequencies and excitation energies were calculated with standard Slatertype-orbital (STO) basis sets with triple-zeta quality double plus polarization functions (TZ2P) for all atoms. The FTIR, UV-Vis spectra and assignment of principal transitions and total density of state (TDOS) were extracted using the GaussSum 2.2 program. The comparison between experimental and calculated values shows that the experimental results correlate well with the predicted data.
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Y.-K. Cheng, S.-Y. Wu, C.-C. Ding, G.-L. Li, M.-Q. Kuang
University of Electronic Science and Technology of China, Chengdu 610054, P. R. China
Keywords: electron paramagnetic resonance (EPR), Cu
Abstract >>
The electron paramagnetic resonance (EPR) parameters (g factors and hyperfine structure constants) for Cu2+ in [Cu(ipt)(dap)H2O] n × n H2O (ipt is isophthalic acid, dap - 1,3-diaminopropane) are theoretically investigated from the high order perturbation formulas of these parameters for a 3 d 9 ion in a rhombically elongated octahedron. The ligand orbital and spin-orbit coupling contributions are included from the cluster approach because of strong covalency of the system. The nearly axial anisotropies of the g factors and hyperfine structure constants are correlated to the significant elongation distortion of the five-fold coordinated Cu2+ (in a distorted square pyramidal [CuN2O3] group). Nevertheless, the perpendicular anisotropies arising from the nonequivalent planar ligands are largely concealed by the experimental uncertainties. The theoretical analysis of the EPR behaviours for [Cu(ipt)(dap)H2O] n × n H2O would be helpful to understand the local structures and properties of this and relevant systems.
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O. G. Shakirova1, L. G. Lavrenova2,3, E. V. Korotaev2, L. A. Sheludyakova2,3, V. A. Varnek2, M. A. Shestopalov2,3, Yu. V. Mironov2,3
1Komsomolsk-on-Amur State Technical University, Komsomolsk-on-Amur, Russia 2Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia 3Novosibirsk National Research State University, Novosibirsk, Russia
Keywords: координационные соединения, железо(II), трис(пиразол-1-ил)метан, октаэдрические кластерные комплексы, спин-кроссовер, термохромизм, coordination compounds, iron(II), tris(pyrazol-1-yl)methane, octahedral cluster complexes, spin-crossover, thermochromism
Abstract >>
Synthesis procedures for new coordination compounds of iron(II) with tris(pyrazol-1-yl)methane (HC(pz)3), containing cluster anions in the outer sphere, of the composition [Fe{HC(pz)3}2][Mo6Cl14]×2H2O (I), [Fe{HC(pz)3}2][Mo6Br14]×H2O (II), and [Fe{HC(pz)3}2]2[Re6S8(CN)6]×2H2O (III) are developed. The compounds are studied by static magnetic susceptibility, electronic, IR, and Mössbauer spectroscopic methods. The magnetochemical study shows that in the polycrystalline phases of all compounds the spin-crossover 1 А 1 Û 5 - 2 is observed which is accompanied by thermochromism.
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B. Safak1, Y. Yahsi1, E. Gungor1, H. Kara1,2
1Balikesir University, Balikesir, Turkey 2Mugla Sitki Kocman University, Mugla, Turkey
Keywords: Schiff-base ligand, iron(III) complex, X-ray crystal structure analysis, magnetic properties
Abstract >>
A new dinuclear Fe(III) complex, [Fe(5-MeOL1)(OH)0.86(CH3O)0.14]2×2(CH3OH), [H2-5-MeOL1 = N,N¢-bis(5-methoxy-2-hydroxybenzylidene)-2,2-dimethylpropane-1,3-diamine], 1 has been synthesized and characterized by single crystal structure analysis. The structure of 1 consists of two Fe(III) centers with one tetradentate schiff base ligand (N2O2) which are bridged by dihydroxo/dimethoxo groups to yield a Fe2O2 core. Complex 1 exhibits weak antiferromagnetic exchange interaction between Fe(III) ions with J = -0.21 cm-1.
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H. Zhang1, L. Kong2, D. Zhang1
1Shandong University of Technology, Zibo 255049, P. R. China 2Liaocheng University, Liaocheng 252059, P. R. China
Keywords: cyanide-bridged, hydrogen bond, synthesis, crystal structure, magnetic properties
Abstract >>
By employing trans -dicyano or pentacyanometalate as building block and using a bicompartimental Schiff-base based manganese(III) compound as assemble segment, two new cyanide-bridged heterometallic Fe(III)-Mn(III) complexes {[Mn(L)(H2O)][Febpb(CN)2]}×2CH3OH (1) and {[Mn(L)(H2O)]2×[Fe(CN)5NO]} (2) (bpb2- = 1,2-bis(pyridine-2-carboxamido)benzenete, L = N,N¢-ethylene-bis(3-ethoxysalicylideneiminate) have been synthesized and characterized by elemental analysis, IR spectroscopy and X-ray structure determination. Single X-ray diffraction analysis reveals binuclear FeMn and trinuclear FeMn2 structure, respectively, in which the cyanide precursor acts as mono- or bidentate ligand to connect the Mn(III) Schiff-base unit(s). Furthermore, these two complexes are self-complementary through coordinated aqua ligands from one complex and the free O4 compartments from the neighboring complex, giving dimeric and 1D single chain supramolecular structure. Investigation of the magnetic susceptibility of 1 reveals weak antiferromagnetic coupling between the adjacent Mn(III) ions. Based on the binuclear FeMn model, best fit of the magnetic susceptibilities of 1 leads to the magnetic coupling constants J = -1.37 cm-1 and zJ ¢ = - 0.72 cm-1 (1).
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Y. Yahsi1, E. Gungor1, C. Kazak2, H. Kara1,3
1Balikesir University, Faculty of Art and Science, Balikesir, Turkey 2Ondokuz Mayis University, Faculty of Art and Science, Samsun, Turkey 3Mugla Sitki Kocman University, Mugla, Turkey
Keywords: synthesis, Schiff-base ligands, iron (III) complexes, X-ray crystal structure analysis, oxo bridged structure
Abstract >>
A dimeric [{Fe(5-ClL1)}2(m-O)], [H2-5-ClL1 = N,N¢-bis(5-Chloro-2-hydroxybenzylidene)- 2-methylpropane-1,2-diamine] tetradentate Schiff-base complex, 1, has been synthesized and its crystal structure has been determined by single crystal X-ray diffraction analysis. Structural analysis of complex 1 shows that the complex is a centrosymmetric dimer. Each of the Fe(III) ions has a five-coordinate geometry and one oxygen atom bridges two Fe(III) ions to form a m-oxo structure. The geometry around iron atom can be described as a square based pyramid with the FeN2O2 coordination plane and oxo ligand.
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A. Abedi, E. Saemian, V. Amani
Islamic Azad University, P.O. Box: 19585-936, Tehran, Iran
Keywords: nickel(II), 5,5'-dimethyl-2,2'-bipyridine, crystal structure, luminescent properties
Abstract >>
[Ni(5,5'-dmbipy)2Cl2]×3H2O (1) complex was obtained from the reaction of NiCl2×6H2O with 5,5'-dimethyl-2,2'-bipyridine (5,5'-dmbipy) in a mixture of CH3OH/CH3CN. This complex was characterized by elemental analysis, IR, UV-Vis and luminescence spectroscopy, and its structure was determined by the single-crystal diffraction method. The Ni atom has a distorted octahedral coordination by four N atoms from two 5,5'-dmbipy ligands and two Cl- anions.
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E. S. Vikulova1, S. I. Dorovskikh1, A. D. Shushanyan2, N. V. Kuratieva2, P. A. Stabnikov1, L. N. Zelenina2, N. B. Morozova2
1Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia 2Novosibirsk National Research State University, Novosibirsk, Russia
Keywords: синтез, ОІ-иминокетонаты меди(II), рентгеноструктурный анализ, термогравиометрия, дифференциально-сканирующая калориметрия, synthesis, copper(II) ОІ-iminoketonates, single crystal X-ray diffraction analysis, thermogravimetry, differential scanning calorimetry
Abstract >>
The single crystal X-ray diffraction (XRD) method was used to determine the structure of the [Cu(mi-tfac)2] (mi-tfac = MeC(O)CHC(NMe)CF3) complex at the temperature of 150 K. The crystallographic data are as follows: space group Pnna , a = 11.8798(16) Å, b = 12.0315(16) Å, c = 10.6259(14) Å, V = 1518.8(4) Å3, Z = 4, R = 0.0288. The structure is molecular, the coordination environment of copper in the molecule adopts a distorted tetrahedral geometry. The Cu-O and Cu-N distances are 1.9182(13) Å and 1.9610(16) Å respectively, the OCuN chelate angle is 94.18(5)°. The thermal properties of the compounds [Cu(mi-tfac)2] and [Cu(RC(O)CHC(NMe)R)2] (R = Me, t Bu) in the condensed phase have been studied by the methods of thermogravimetry and differential scanning calorimetry. The thermodynamic characteristics of the melting processes have been determined.
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M. Ben Nasr1, E. Aubert1, V. Ferretti2, E. Espinosa1, P.S.P. Silva3, L.C.J. Pereira4, M.R. Silva3
1Vandoeuvre les Nancy, Nancy, France 2Center for Structural Diffractometry, Ferrara, Italy 3University of Coimbra, Coimbra, Portugal 4Instituto Superior TГ©cnico, UTL, Bobadela LRS, Portugal
Keywords: coordination compounds, copper(II) complex, crystal structure, magnetism, IR spectroscopy, cryomagnetic
Abstract >>
A new Cu (II) complex with bidentate o-phenanthroline (phen) ligand, ([Cu(phen)]2(H2PO4)2××HPO4)2(H3PO4)4, has been synthesized and characterized by single crystal X-ray diffraction, IR spectroscopy and magnetic data. The crystal structural analysis shows that the title compound contains two phosphate-bridged dimeric units ([Cu(phen)]2(H2PO4)HPO4), which are crystallographically independent. In these units, each copper atom is five coordinated and the geometry around the Cu(II) can be described as slightly distorted square-based pyramidal, with parameter varying between 0.001 and 0.04. The crystal structure is stabilized by O-H…O and C-H…O hydrogen bonds between the dimeric units and the phosphoric acid molecules. In addition, the organic ligands are associated by π-π stacking interactions between neighboring non-nitrogen aromatic rings. The infrared spectrum recorded at room temperature was interpreted on the basis of data published in the literature. The magnetic susceptibilities data show a weak intra-dimer ferromagnetic interaction with J = 31.8 K.
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A. Aguirrechu-ComerГіn1, J. PasГЎn1, J. GonzГЎlez-Platas1, J. Ferrando-Soria2, R. HernГЎndez-Molina3
1Universidad de La Laguna, Tenerife, Spain 2Texas A&M University, Texas 77842, USA 3Instituto Universitario de Quimica Bioorganica, La Laguna, Tenerife, Spain
Keywords: copper, structures, halides, magnetism
Abstract >>
The preparation of four new copper(II) complexes with different N-donor ligands [CuBr2×(2-benzylpyridine)2] (1), [CuBr2(2-benzylpyridine)(2,2'-bipyridine)]×H2O (2), [CuBr2(3-methyl-2-phenylpiridine)2] (3), [Cu(picolinate)2]×KI (4) from copper(I) halides as starting material is described. During the preparation of compound 4 a ligand oxidation reaction took place to give the picolinate ligand starting from 2-(2-methylaminoethyl)pyridine. The complexes were characterized by elemental analyses, IR spectroscopy and crystallographic studies. Single crystal X-ray diffraction analysis of the complexes reveals their monomeric penta- and tetracoordinated nature. For all compounds, the copper(II) present a common square planar coordination except for compound 2 which is five coordinated in a quasi-square pyramidal configuration with t of 0.29. The Cu-N distances for these compounds are in the range of 1.959(4)-2.041(3) Å, Cu-O distance was 1.961(3) Å and Cu-Br distances were in the range of 2.4052(4)-2.4381(6) Å for the square base configuration while for apical distance it was 2.6745(7) Å. Magnetic properties have been investigated for all compounds in the temperature range 2-300 K. Compound 1 shows weak antiferromagnetic intermolecular interaction.
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W.-L. Hou1, G.-Y. Dong2, X.-X. Wang2, K. Van Hecke3
1Hebei Normal University of Science and Technology, Qinhuangdao, Hebei, P. R. China 2Hebei United University, Tangshan, Hebei, P. R. China 3Ghent University, Ghent, Belgium
Keywords: bis(benzimidazole) ligand, crystal structure, fluorescence, zinc(II) complex
Abstract >>
A new Zn(II) coordination polymer, {[Zn(npht)(L)0.5(H2O)]×H2O} n (L = 1,4-bis(2-methylbenzimidazol-1-ylmethyl)benzene, H2npht = 3-nitrophthalic acid) has been hydrothermally synthesized and characterized by elemental analysis, IR, XRPD, and single-crystal X-ray diffraction. The Zinc(II) coordination compound exhibits a 1D linear chain, which is further assembled into a 2D supramolecular layer via two modes of classial hydrogen bonding interactions. The fluorescence properties and thermal stability of the complex have been investigated in the solid state.
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H.H. Li, Y.Q. Zhao, G.Y. Li, G.H. Cui
Hebei United University, Tangshan, Hebei Province, P. R. China
Keywords: bis(benzimidazole), Cd(II) complex, crystal structure, fluorescence
Abstract >>
A new coordination polymer, {[Cd(bbmb)(bdc)]} n (bbmb = 1,1¢-(1,4-butanediyl)bis-(2-methylbenzimidazole), H2bdc = 1,3-benzenedicarboxylic acid) was synthesized under hydrothermal conditions. The complex was structurally characterized by single crystal X-ray diffraction analyses, infrared spectroscopy (IR), elemental analyses. The compound crystallizes in the monoclinic system, space group P 21/ c with a = 10.860(6) Å, b = 13.115(7) Å, c = 21.009(9) Å, b = 120.94(2)°, V = 2567(2) Å3, Z = 4, C28H26CdN4O4, Mr = 594.93, Dc = 1.540 g/cm3, m = = 0.893 mm-1. Each cadmium center is six coordinated with four O atoms from two bdc2- anions, and two N atoms of two bbmb ligands. The complex features a 4-connected 2D (4, 4) sheet with a point symbol {42.62}. Fluorescence properties of the title complex were investigated.
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X. Li
Zunyi Normal College, Zunyi 563002, P. R. China
Keywords: yttrium, coordination polymer, crystal structure, hemimellitic acid
Abstract >>
A two-dimensional (2D) coordination polymer, formulated as [Y4(m3-OH)4(hma)(cba)5] n × × n (Hcba) (1), is synthesized by the synergistic coordination of hemimellitate (H3hma) and 4-chlorobenzoate (Hcba) ligands with Y2O3 under hydrothermal conditions. It has been characterized by single-crystal X-ray diffraction, powder XRD, thermogravimetric analysis, elemental analysis and infrared spectroscopy. Single-crystal X-ray diffraction reveals that it crystallizes in the triclinic crystal system, P space group. Unit cell parameters: a = 11.0280(6) Å, b = 14.5791(10) Å, c = 18.9515(12) Å, a = 72.233(6)°, b = 82.641(5)°, g = 70.933(5)°, V = 2741.1(3) Å3, Z = 2. The asymmetric unit contains a [Y4(m3-OH)4]8+ core which is extended into an infinite {[Y4(m3-OH)4]8+} n chain along the direction of a axis. Every {[Y4(m3-OH)4]8+} n chain is further connected to two neighboring chains by hma3- ligands along the direction of b axis, forming a 2D yttrium-organic layer in the ab plane. Adjacent layers are further packed with each other via hydrophobic interactions to form a three-dimensional (3D) structure.
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A. V. Gerasimenko, R. L. Davidovich, M. A. Pushilin, V. B. Logvinova
Institute of Chemistry, Far East Branch, Russian Academy of Sciences, Vladivostok, Russia
Keywords: синтез, кристаллическая структура, комплексный фторид, цирконий, гафний, полиморфная модификация, конформер, 4-амино-1,2,4-триазол, synthesis, crystal structure, complex fluoride, zirconium, hafnium, polymorph, conformer, 4-amino-1,2,4-triazole
Abstract >>
New hybrid organic-inorganic complex zirconium and hafnium fluorides with the 4-amino-1,2,4-triazolium cation (C2H5N4)2MF6 (M = Zr, Hf, Zr x Hf1- x ), which crystallize in two polymorphs (monoclinic ( P 21/ n , Z = 4) and triclinic ( P , Z = 2)) are synthesized and structurally studied for the first time. The structures of both polymorphs are composed of hydrogen bonded (N-H⋯F and C-H⋯F) 4-amino-1,2,4-triazolium cations protonated via the nitrogen atom in site 1 and complex [M2F12]4- anions that are centrosymmetric dimers formed by edge-sharing pentagonal bipyramids MF7 (M = Zr, Hf, Zr x Hf1- x ). It is found that in the structures studied 4-amino-1,2,4-triazolium cation occur simultaneously as cis- and trans- conformers. The packing character of structural units in the unit cells of the studied crystals is discussed along with the structure of the neutral and protonated forms of 4-amino-1,2,4-triazole.
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M.M. Ftini
Faculte des sciences Monastir, Monastir, Tunisie
Keywords: synthesis, polyoxometalate, organic-inorganic hybrid solids, cyclic voltammetry, UV visible spectrum
Abstract >>
A novel inorganic-organic hybrid salt, hexanediammonium heptamolybdate (C6H18N2)2[H2Mo7O24]×7H2O has been synthesized and characterized by elemental analyses, IR, TGA, cyclic voltammetry, UV and X-ray single crystal diffraction. It crystallizes in triclinic space group P -1 with a = 10.0619(2) Å, b = 12.059(2) Å, c = 20.044(3) Å, a = 97.06(1)°, b = 91.56(1)°, g = 110.59(2)° and Z = 2. The crystal structure shows that seven MoO6 distorted octahedra share edges which have four ranges of Mo-O bond distances. The heptamolybdate anion of the crystal has approximate mm 2 point symmetry and its structure is similar to that observed in other heptamolybdates. The titled compound consists of the protonated hexanediamine cations and the inorganic [H2Mo7O24]4- oxomolybdate anions, linked by hydrogen-bonding interactions.
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M. Gowri1, T. Srinivasan2, D. Velmurugan2
1Avinashilingam University for Women, Coimbatore - 641 043, Tamilnadu, India 2University of Madras, Guindy Campus, Chennai - 600 025, Tamilnadu, India
Keywords: Ru(II) complex, triphenyl arsine, pyridine, chloride, carbonyl complex, crystal structure
Abstract >>
The title complex [Ru(Cl)2(CO)(py)2(AsPh3)], was synthesized and characterized. The molecular structure and crystal structures are determined by X-ray crystallography. The dihedral angle between the two cis -pyridine rings is 73.3(2)°, which shows that they are almost orthogonal to each other. The molecular structure is stabilized by inter-molecular and intra-molecular C-H…Cl interactions. The molecular structure is further stabilized by interactions between the aromatic rings.
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S. N. Vorobieva1,2, I. A. Baidina1, A. V. Belyaev1, I. V. Korolkov1,2, N. I. Alferova1
1Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia 2Novosibirsk National Research State University, Novosibirsk, Russia
Keywords: родий, ацидопентааквакомплексы, координационные соединения, кристаллическая структура, rhodium, acido-penta-aqua complexes, coordination compounds, crystal structure
Abstract >>
The crystal structures of the compounds with the composition [Rh(H2O)5Cl](C7H7O3S)2 (I) and Cs[Rh(H2O)5NO3](C7H7O3S)3×H2O (II) are determined. Crystallographic data for I: a = 10.063(10) Å, b = 7.771(8) Å, c = 13.524(15) Å; b = 100.44(3)°, space group P 21, Z = 2, d calc = 1.823 g/cm3; for II: a = 16.221(3) Å, b = 9.646(19) Å, c = 21.307(4) Å, b = 92.06(3)°, space group P 21, Z = 8, d calc = 1.833 g/cm3. The compounds are characterized by IR spectroscopy and powder X-ray diffraction. The rhodium atoms have a distorted octahedral environment consisting of five oxygen atoms of coordinated water molecules and one chloride ion (I)/oxygen atom of the nitrate ion (II) with the following distances: Rh-OH2O of 1.993-2.075 Å and Rh-Cl of 2.270 Å for I; Rh-OH2O of 1.996-2.031 Å and Rh-ONO3 of 1.990 Å for II.
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G.-S. Li, H.-L. Zhang
Zhengzhou University of Light Industry, Zhengzhou 450002, P. R. China
Keywords: silver complex, polymeric complex, 3-aminopyrazine-2-carboxylate, crystal structure, cytotoxicity
Abstract >>
A novel ladder-like polymeric silver(I) complex, [Ag2L2] n ×2 n H2O, where L is 3-aminopyrazine-2-carboxylate, was obtained by the reaction of 3-aminopyrazine-2-carboxylic acid and silver oxide in aqueous ammonia. The complex was characterized by elemental analysis, IR spectra and single crystal X-ray determination. The smallest repeat unit contains a [Ag2L2] moiety and two water molecules. The Ag⋯Ag distance is 3.176(1) mmol. Each Ag atom is in a Y-shaped coordination, with one carboxylate O and two pyrazine N atoms from two ligands. In the crystal structure of the complex, the dinuclear silver moieties are linked through 3-aminopyrazine-2-carboxylate ligands, to form 1D ladder-like chain along the b axis. The water molecules are linked to the silver chain through hydrogen bonds. There are p⋯p interactions between the chains. The complex showed effective cytotoxic property on human lung cancer cell line A549.
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Y.Y. Li, L. Wang, J. Zhang, C. Ma, S.K. Liang, L.F. Li, F.C. Zhao, Y. Meng, E.J. Gao
Shenyang University of Chemical Technology, Shenyang, 110142, P.R. China
Keywords: 1,4-bis(4-pyridylmethyl)piperazine, T-shaped building blocks, metal complex
Abstract >>
Coordination of a pyridine-based bridging ligand, 4-bpmp, with cadmium nitrate afforded an infinite ladder-type complex {[Cd(4-bpmp)2(H2O)Cl2]} n (A) (4-bpmp = 1,4-bis(4-pyridylmethyl)piperazine) containing T -shaped building blocks. IR spectra, elemental analysis, and X-ray single-crystal diffraction were carried out to determine the composition and crystal structure of complex A. Inclined interpenetration of infinite ladders was observed in the solid structure. The combined work demonstrates the ability of bipyridyl coordination polymer leads to a novel metal complex with impressive structural motif.
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A. A. Udovenko, R. L. Davidovich, V. B. Logvinova
Institute of Chemistry, Far Eastern Branch, Russian Academy of Sciences, Vladivostok, Russia
Keywords: гептафторидотанталат(V), кристаллическая структура, комплексный анион, 4-амино-1,2,4-триазол, моношапочная тригональная призма, пентагональная бипирамида, heptafluoridotantalate(V), crystal structure, complex anion, 4-amino-1,2,4-triazole, monocap trigonal prism, pentagonal bipyramid
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For the first time, the fluoridotantalates(V) with the mono- and diprotonated 4-amino-1,2,4-triazolium cation of the heterocyclic base (C2H5N4)2TaF7 and (C2H6N4)TaF7×H2O, are synthesized and their crystal structures are determined. The orthorhombic crystals of (C2H5N4)2TaF7 (space group Cmc 21) are formed of complex [TaF7]2- anions with the configuration of monocap trigonal prism and the monoprotonated (C2H5N4)+ cations, one of which is statistically disordered. The crystal structure of (C2H6N4)TaF7×H2O (space group Pna 21) consists of the pentagonal bipyramidal complex [TaF7]2- anions, the diprotonated (C2H6N4)2+ cations, and the molecules of crystallization H2O. In the structure of I, the (C2H5N4)+ cations simultaneously exist as cis- and trans- conformers. The formation of the diprotonated 4-amino-1,2,4-triazolium cation (C2H6N4)2+ was revealed for the first time. Via ionic interactions and N-H⋯F, N-H⋯N, and O-H⋯F hydrogen bonds, the units in I and II are arranged in a three-dimensional structure.
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V. A. Afanas’eva1, L. A. Glinskaya1, D. A. Piryazev1, S. A. Gromilov1,2
1Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia 2Novosibirsk National Research State University, Novosibirsk, Russia
Keywords: золото, рений, тетраазаметаллоцикл, комплексная соль, рентгеноструктурный анализ, рентгенофазовый анализ, кристаллохимия, термолиз, gold, rhenium, tetraazametallocycle, complex salt, single crystal X-ray diffraction analysis, powder X-ray diffraction analysis, crystal chemistry, thermolysis
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Acyclic tetraazametal gold(III) perrhenate complex [Au(C9H19N4)](ReO4)2 is synthesized. The 3D crystal structure of the complex is stabilized by weak secondary interactions (N-H…O, C-H…O, С-H…Au hydrogen bonds, and Au…O contacts). The translation sublattice method shows that the motif of the mutual arrangement of cations can be considered to be pseudohexagonal. The product of the thermal decomposition of [Au(C9H19N4)](ReO4)2 in a hydrogen atmosphere is a mixture of nanocrystalline phases (HCP phases based on Re and Au) with the coherent scattering region of 24 nm and 34 nm, respectively.
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M. Celebi1, M.S. Agirtas1, A. Dundar2
1Yuzuncu Yil University, 65080, Van, Turkey 2Mardin Artuklu University, 47000, Mardin, Turkey
Keywords: synthesis, metal, phthalocyanines, aggregation, antioxidant, antibacterial activity
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In this study, a novel phthalonitrile, 4-chloro-5-(2-((2-hydroxyethyl)( p -tolyl)amino)ethoxy)phthalonitrile (3), and its metallophthalocyanine derivatives (4-6) are prepared by cyclotetramerization with appropriate metal salts in dimethylformamide. The newly prepared compounds have been characterized by several spectroscopic techniques. All compounds are evaluated for their antioxidant and antibacterial potential. For the antioxidant studies, three tests are applied; DPPH (2,2-diphenyl-1-picrylhydrazylradical) scavenging, metal chelating and reducing power activity. Compound 4 exhibits the best DPPH scavenging activity as 35.2 % at 100 mg/L concentration. The metal chelating activities of compounds 3 and 4 are 69.7 % and 56.4 %, respectively. Reducing power activities of compounds 3 and 4 are higher than a-tocopherol which is used as positive control. All compounds show moderate antibacterial activity when compared to the standard antibiotics, amikacin and tetracycline.
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E. Gungor1, H. Kara1,2
1Balikesir University, Balikesir, Turkey 2Mugla Sitki Kocman University, Mugla, Turkey
Keywords: Schiff base, tetranuclear copper(II) complex, antiferromagnetic interaction
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A new tetranuclear complex [Cu4(L)4] (1) (H2L = N-(2-hydroxyethyl)-3-metoxysalicylaldimine) has been synthesized and characterized by crystal structure analysis and magnetic susceptibility. Single-crystal X-ray diffraction studies reveal that complex 1 contains three independent Cu4O4 open-cubane cores of 4+2 type (four short and two long Cu⋯Cu distances), where the copper(II) centers are linked by alkoxo-bridges. Each copper(II) ion have a distorted square-pyramidal geometry. Variable-temperature magnetic susceptibility measurements on the tetranuclear complex 1 in the range 2-300 K indicate dominant antiferromagnetic coupling ( J = -108.46) between copper(II) centers.
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S. Ahmad1, A. Yousaf1, M.N. Tahir2, A.A. Isab3, M. Monimul-Mehboob3, W. Linert4, M. Saleem5
1University of Engineering and Technology, Lahore 54890, Pakistan 2University of Sargodha, Sargodha, Pakistan 3King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia 4Vienna University of Technology, A-1060 Vienna, Austria 5Jubail University College, P. O. Box 10074, Jubail Industrial City 31961, Saudi Arabia
Keywords: synthesis, silver nitrate, amino acids, arginine, crystal structure
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A silver(I) complex of arginine (arg), [Ag(arg)]NO3×0.5H2O (1) was prepared and characterized by elemental analysis, IR and NMR spectroscopy, and X-ray crystallography. The IR and NMR spectroscopic data confirmed the coordination of the ligand to silver(I). The structure of 1 shows that it is polymeric with each silver atom bound to the carboxyl O atom of one arginine ligand and to the amino N atom of another adopting a linear coordination environment. The two coordinate N-Ag-O units are repeated to form infinite chains. The molecular structure is stabilized by N-H…O and C-H…O hydrogen bonds. Antimicrobial activities of the complex were evaluated by minimum inhibitory concentration against gram-negative bacteria ( E. coli , P. aeruginosa ), molds ( A. niger, P. citrinum ) and yeasts ( C. albicans, S. cerevisiae ).
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