scholarly journals The Synthesis, and the Crystal and Molecular Structures of Tetraethylammonium [Aquaheptakis(thiocyanato)lanthanoidate(III)], [(C2H5)4N]4[M(SCN)7(H2O)], (M=La, Ce, Pr; Nd, Dy, Er): The Complexes in a Cubic Octa-Coordination Geometry

1988 ◽  
Vol 61 (8) ◽  
pp. 2805-2810 ◽  
Author(s):  
Yoshikuni Tateyama ◽  
Yasumitsu Kuniyasu ◽  
Yasuo Suzuki ◽  
Akira Ouchi
Keyword(s):  
Molecular Structures ◽  
Coordination Geometry ◽  
Crystal And Molecular Structures

Kupfer(I)-Komplexe mit ungesättigten Stickstoffliganden, V / Kupfer(I)-Komplexe mit Diazadienen als Chelate und Brücken: Röntgenstrukturenuntersuchungen an (DAD)Cu(μ-Cl)2Cu(DAD), [(DAD)2Cu]⁺ (CuCl2)-, (DAD)CuCl, [μ-(DAD)2Cu5Cl5]n und [μ-(DAD)Cu(OTf)]n (DAD = Diazadien) / Copper(I) Complexes with Unsaturated Nitrogen Ligands, V Copper(I) Complexes with Chelating and Bridging Diazadienes: X-Ray Diffraction Studies of (DAD)Cu(μ-Cl)2Cu(DAD), [(DAD)2Cu]+ (CuCl2)-, (DAD)CuCl, [μ-(DAD)2Cu5Cl5]n and [μ-(DAD)Cu(OTf)]n (DAD = Diazadiene)

1990 ◽  
Vol 45 (10) ◽  
pp. 1369-1382 ◽  
Author(s):  
Heindirk tom Dieck ◽  
Lutz Stamp
Keyword(s):  
Coordination Polymer ◽  
Molecular Complexes ◽  
Molecular Structures ◽  
Coordination Geometry ◽  
Halide Ions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nitrogen Ligands ◽  
Crystal And Molecular Structures ◽  
Irregular Geometries

Diazadienes RN = CR′-CR′ = NR (DAD) form molecular complexes with copper(I) halides of composition (DAD)CuX, the structures of which vary from [(DAD)2Cu]+(CuCl2)⁻ with a non-tetrahedral bis(chelated) cation, over [(DAD)CuCl]2 with asymmetrically bridging chloro ligands to planar three-coordinate (DAD)CuCl. The composition of the isolated complexes depends on the relative concentrations or on the solvent. The “soft” coordination geometry of copper is underlined by the structure of the coordination polymer of composition (DAD)2Cu5Cl5, in which Cu atoms of coordination number 2, 3 and 4 and very irregular geometries are encountered and where the DAD ligands are exclusively bridging. Halide ions and sp2-nitrogen donors are very competitive. Bridging DAD ligands are also encountered in (DAD)Cu-Y with the less nucleophilic anions trifluoromethane-sulphonate or perchlorate. Crystal and molecular structures are established for all these coordination geometries and the causes are discussed for the coordination flexibility of copper(I)

Cyclopentadienyl-Ruthenium and -Osmium Chemistry. XL. X-Ray Crystal Structures of MBr (PPh3)2(η-C5H5).CH2Cl2 (M = Ru, Os)

1995 ◽  
Vol 48 (11) ◽  
pp. 1887 ◽  
Author(s):  
MI Bruce ◽  
PJ Low ◽  
BW Skelton ◽  
ERT Tiekink ◽  
A Werth ◽  
...  
Keyword(s):  
Structural Parameters ◽  
Molecular Structures ◽  
Coordination Geometry ◽  
Chloro Complexes ◽  
Triclinic Space Group ◽  
Full Matrix ◽  
X Ray ◽  
Crystal And Molecular Structures ◽  
Cell Dimensions ◽  
Unit Cell Dimensions

The crystal and molecular structures of MBr (PPh3)2(η-C5H5).CH2Cl2 (M = Ru and Os) have been determined. A revised synthesis of the bromo osmium complex is given. The coordination geometry about the metal atom is based on a distorted octahedron with one face being occupied by the cyclopentadienyl group [average Ru -C(Cp) 2.214(3), Os-C(Cp) 2.177(3)Ǻ] and the other by the bromide [ Ru -Br 2.5683(8), Os-Br 2.5438(9)Ǻ] and the two phosphorus atoms [ Ru -P 2.323(2), 2.329(1); Os-P 2.290(2), 2.297(2)Ǻ]. Structural parameters are compared with those of the corresponding chloro complexes and differ only minimally. Crystals of MBr (PPh3)2(η-C5H5).CH2Cl2 are triclinic, space group Pī , with unit cell dimensions ( Ru [Os]): a 14.374(5) [14.276(4)], b 14.057(4) [13.959(3)], c 10.012(5) [9.903(3)]Ǻ, α 99.43(3) [99.79(2)], β 105.60(3) [105.74(2)], γ 100.42(3) [100.39(2)]°, V 1868(1) [1817.7(9)] Ǻ3, Z 2. The structures were refined by a full-matrix least-squares procedure to R 0.050 [0.036] for 7365 [5108] reflections with I ≥ 3σ(I).

Complexes containing unsaturated medium rings: The crystal and molecular structures of two rhodium(I) complexes

1978 ◽  
Vol 31 (4) ◽  
pp. 781 ◽  
Author(s):  
R Mason ◽  
GR Scollary
Keyword(s):  
Molecular Structures ◽  
Monoclinic Space Group ◽  
Coordination Geometry ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
X Ray ◽  
Crystal And Molecular Structures ◽  
Square Planar ◽  
Medium Rings

The crystal and molecular structures of two rhodium(I) complexes with long-chain alkyne- or alkene-α,ω-diyldiphosphines have been determined by single-crystal X-ray diffraction techniques. RhCl(CO){But2P(CH2)4C≡C(CH2)4PBut2} crystallizes in the orthorhombic space group Pna21 with a 21.991 (2), b 11.915(1), c 11.890(1) Ǻ and Z 4. The structure was refined by least-squares methods to a conventional R factor of 0.097 for 1768 independent reflections (Mo Kα diffraction data). The rhodium ion is in a square-planar coordination geometry with trans-phosphorus atoms; the unsaturated (alkynyl) group is not bonded to the rhodium. Crystals of RhCl{But2P(CH2)2CH=CH(CH2)2- PBut2} are monoclinic, space group P21/c, a 20.783(12), b 8.580(4), c 14.799(9) Ǻ, β 100.70(2)°, Z 4. The structure analysis has converged to R 0.069 for 1417 reflections (Mo Kα diffractometry); the coordination geometry of the rhodium is again planar with the ethylenic group occupying a single bonding site. The effect of ring size on the rhodium-phosphorus bond lengths is discussed.

scholarly journals Crystal and molecular structures of a binuclear mixed ligand complex of silver(I) with thiocyanate and 1H-1,2,4-triazole-5(4H)-thione

2020 ◽  
Vol 76 (1) ◽  
pp. 42-47
Author(s):  
Janjira Kreaunakpan ◽  
Kittipong Chainok ◽  
Nathan R. Halcovitch ◽  
Edward R. T. Tiekink ◽  
Teerapong Pirojsirikul ◽  
...  
Keyword(s):  
Mixed Ligand Complex ◽  
Three Dimensional ◽  
Molecular Structures ◽  
Coordination Geometry ◽  
Tetrahedral Coordination ◽  
Ligand Complex ◽  
Face To Face ◽  
Crystal And Molecular Structures ◽  
Hirshfeld Surfaces ◽  
Thiocyanate Ligand

The complete molecule of the binuclear title complex, bis[μ-1H-1,2,4-triazole-5(4H)-thione-κ2 S:S]bis{(thiocyanato-κS)[1H-1,2,4-triazole-5(4H)-thione-κS]silver(I)}, [Ag2(SCN)2(C2H3N3S)4], is generated by crystallographic inversion symmetry. The independent triazole-3-thione ligands employ the exocyclic-S atoms exclusively in coordination. One acts as a terminal S-ligand and the other in a bidentate (μ2) bridging mode to provide a link between two AgI centres. Each AgI atom is also coordinated by a terminal S-bound thiocyanate ligand, resulting in a distorted AgS4 tetrahedral coordination geometry. An intramolecular N—H...S(thiocyanate) hydrogen bond is noted. In the crystal, amine-N—H...S(thione), N—H...N(triazolyl) and N—H...N(thiocyanate) hydrogen bonds give rise to a three-dimensional architecture. The packing is consolidated by triazolyl-C—H...S(thiocyanate), triazolyl-C—H...N(thiocyanate) and S...S [3.2463 (9) Å] interactions as well as face-to-face π–π stacking between the independent triazolyl rings [inter-centroid separation = 3.4444 (15) Å]. An analysis of the calculated Hirshfeld surfaces shows the three major contributors are due to N...H/H...N, S...H/H...S and C...H/H...C contacts, at 35.8, 19.4 and 12.7%, respectively; H...H contacts contribute only 7.6% to the overall surface.

A Solvent-Dependent and Electrochemically Controlled Self-Assembling/Disassembling System

2003 ◽  
Vol 68 (9) ◽  
pp. 1647-1662 ◽  
Author(s):  
Valeria Amendola ◽  
Massimo Boiocchi ◽  
Yuri Diaz Fernandez ◽  
Carlo Mangano ◽  
Piersandro Pallavicini
Keyword(s):  
Equilibrium Mixture ◽  
Bidentate Ligand ◽  
Molecular Structures ◽  
The Self ◽  
Molar Ratio ◽  
Crystal And Molecular Structures ◽  
Self Assembling ◽  
Irreversible Oxidation ◽  
Irreversible Reduction ◽  
Metal Ligand

The bis-bidentate ligand R,S-1,2-diphenyl-N,N'-bis(2-quinolinemethylidene)ethane-1,2-diamine (ligand 4), containing two (iminomethyl)quinoline moieties separated by a cis-1,2-diphenylethylene spacer, forms stable complexes with both CuI and CuII. With CuII, the monomeric 1:1 complex [CuII(4)]2+ is obtained both in CH3CN and CH2Cl2. With CuI and overall 1:1 metal/ligand molar ratio, an equilibrium mixture is obtained in CH3CN, consisting of [CuI(4)2]+, [CuI2(4)2]2+ and [CuI2(4)(CH3CN)4]2+. The preponderant species is the two-metal one-ligand "open" complex [CuI2(4)(CH3CN)4]2+, in which each Cu+ cation is coordinated in a tetrahedral fashion by one (iminomethyl)quinoline unit and by two CH3CN molecules. Precipitation from the equilibrium mixture yields only crystals of [CuI2(4)(CH3CN)4](ClO4)2·2CH3CN, whose crystal and molecular structures have been determined. On the other hand, in the poorly coordinating CH2Cl2 solvent, only the dimeric helical [CuI2(4)2]2+ complex is obtained, when the overall metal/ligand 1:1 molar ratio is chosen. Addition of large quantities of acetonitrile to solutions of [CuI2(4)2]2+ in dichlorometane results in the formation of [CuI2(4)(CH3CN)4]2+, i.e. in the solvent-driven disassembling of the CuI helicate. While electrochemistry in CH3CN is poorly defined due to the presence of more than one CuI species, cyclic voltammetry experiments carried out in CH2Cl2 revealed a well defined behavior, with irreversible oxidation of [CuI2(4)2]2+ and irreversible reduction of [CuII(4)]2+ taking place at separate potentials (∆E ≈ 700 mV). Irreversibility and separation of the redox events are due to the self-assembling and disassembling processes following the reduction and oxidation, respectively.

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