137 research outputs found
catena-Poly[[bis[2-(2,3-dimethylanilino)benzoato-κO]cadmium(II)]-di-μ-3-pyridylmethanol-κ2 N:O;κ2 O:N]
In the crystal structure of the title compound, [Cd(C15H14NO2)2(C6H7NO)2]n, the Cd atom displays a distorted octahedral geometry, including two pyridine N atoms and two hydroxyl O from four symmetry-related 3-pyridylmethanol (3-pyme) ligands and two carboxylate O atoms from mefenamate [2-(2,3-dimethylanilino)benzoate] anions. The Cd atoms are connected via the bridging 3-pyme ligands into chains, that extend in the a-axis direction. The Cd atom is located on a center of inversion, whereas the 3-pyme ligands and the mefenamate anions occupy general positions
Di-μ-acetato-bis[(acetato-κ2 O,O′)bis(isonicotinamide-κN)copper(II)]
The title centrosymmetric bimetallic complex, [Cu2(C2H3O2)4(C6H6N2O)4], is composed of two copper(II) cations, four acetate anions and four isonicotinamide (INA) ligands. The asymmetric unit contains one copper cation to which two acetate units bind asymmetrically; one of the Cu—O distances is rather long [2.740 (2) Å], almost at the limit of coordination. These Cu—O bonds define an equatorial plane to which the Cu—N bonds to the INA ligands are almost perpendicular, the Cu—N vectors subtending angles of 2.4 (1) and 2.3 (1)° to the normal to the plane. The metal coordination geometry can be described as a slightly distorted trigonal bipyramid if the extremely weak Cu—O bond is disregarded, or as a highly distorted square bipyramid if it is not. The double acetate bridge between the copper ions is not coplanar with the CuO4 equatorial planes, the dihedral angle between the (O—C—O)2 and O—Cu—O groups being 34.3 (1)°, resulting in a sofa-like conformation for the 8-member bridging loop. In the crystal, N—H⋯O hydrogen bonds occur, some of which generate a head-to tail-linkage between INA units, giving raise to chains along [101]; the remaining ones make inter-chain contacts, defining a three-dimensional network. There are in addition a number of C—H⋯O bonds involving aromatic H atoms. Probably due to steric hindrance, the aromatic rings are not involved in significant π⋯π interactions
Halogen Bonding in New Dichloride-Cobalt(II) Complex with Iodo Substituted Chalcone Ligands
The synthesis and properties of new chalcone ligand 4I-L ((2E)-1-[4-(1H-imidazol-1-yl)phenyl]-3-(4-iodophenyl)prop-2-en-1-one) and tetracoordinate Co(II) complex [Co(4I-L)(2)Cl-2], (1a), are reported in this article. Upon recrystallization of 1a, the single crystals of [Co(4I-L)(4)Cl-2]center dot 2DMF center dot 3Et(2)O (1b) were obtained and crystal structure was determined using X-ray diffraction. The non-covalent interactions in 1b were thoroughly analyzed and special attention was dedicated to interactions formed by the peripheral iodine substituents. The density functional theory (DFT), atoms in molecule (AIM) and noncovalent interaction (NCI) methods and electronic localization function (ELF) calculations were used to investigate halogen bond formed between the iodine functional groups and co-crystallized molecules of diethyl ether
Tetrakis(4-aminopyridine-κN 1)dichloridocopper(II) monohydrate
The asymmetric unit of the title compound, [CuCl2(C5H6N2)4]·H2O, contains two crystallographically independent complex molecules and two water molecules. The CuII ion in each molecule is six-coordinated in an elongated octahedral geometry, with the equatorial plane defined by four pyridine N atoms of four aminopyridine ligands and the axial positions occupied by two Cl atoms. In the crystal structure, molecules are linked into a three-dimensional framework by C—H⋯Cl, O—H⋯Cl, N—H⋯O, N—H⋯Cl and N—H⋯N hydrogen bonds and C/N—H⋯π interactions involving the pyridine rings
trans-Diaquabis[5-(pyridine-3-carboxamido)tetrazolido-κ2 O,N 1]zinc dihydrate
The title compound, [Zn(C7H5N6O)2(H2O)2]·2H2O, consists of one ZnII ion located on the crystallographic inversion centre, two 5-(pyridine-3-carboxamido)tetrazolide ligands, two coordinated water molecules and two free water molecules. The ZnII ion adopts a slightly distorted octahedral coordination geometry formed by the N,O-chelating ligands and two O water atoms. The pyridine N atoms are not coordinated. In the crystal, complex molecules are connected by N—H⋯O, O—H⋯N and O—H⋯O hydrogen bonds, forming a three-dimensional network
trans-Diaquabis(ethylenediamine-κ2 N,N′)copper(II) bis[3-(3-pyridyl)propionate] dihydrate
The asymmetric unit of the title complex, [Cu(C2H8N2)2(H2O)2](C8H8NO2)2·2H2O, contains one anion, one half-cation and one water molecule. The CuII atom in the [Cu(en)2(H2O)2]2+ cation (en is ethylenediamine) lies on an inversion centre. The four N atoms of the en ligands in the equatorial plane around the CuII atom form a slightly distorted square-planar arrangement, while the slightly distorted Jahn–Teller octahedral coordination is completed by two water O atoms in axial positions. In the crystal structure, intra- and intermolecular N—H⋯O and O—H⋯O hydrogen bonds form a three-dimensional network
Di-μ-nicotinato-κ2 N:O;κ2 O:N-bis[aqua(ethylenediamine-κ2 N,N′)(nicotinato-κN)cadmium(II)] dihydrate
The dinuclear molecule of the title compound, [Cd2(C6H4NO2)4(C2H8N2)2(H2O)2]·2H2O, lies on an inversion centre and forms 12-membered (CdNC3O)2 metallacycles with the two Cd2+ ions bridged by two nicotinate ligands. Both Cd2+ ions display coordination polyhedra with a distorted octahedral geometry that includes two pyridine N atoms from bridging and terminal nicotinate anions, two amine N atoms from chelating ethylenediamine ligands, carboxylate O atoms from bridging nicotinate anions and water O atoms. Intermolecular O—H⋯O and N—H⋯O hydrogen bonds result in the formation of a three-dimensional network, and π–π stacking interactions are observed between symmetry-related pyridine rings of bridging as well as terminal nicotinate anions (the centroid–centroid distances are 3.59 and 3.69 Å, respectively, and the distances between parallel planes of the stacked pyridine rings are 3.53 and 3.43 Å, respectively). The two methylene groups of the ethylenediamine ligand are disordered over two positions; the site occupancy factors are ca 0.8 and 0.2
Deposition of Tetracoordinate Co(II) Complex with Chalcone Ligands on Graphene
Studying the properties of complex molecules on surfaces is still mostly an unexplored research area because the deposition of the metal complexes has many pitfalls. Herein, we probed the possibility to produce surface hybrids by depositing a Co(II)-based complex with chalcone ligands on chemical vapor deposition (CVD)-grown graphene by a wet-chemistry approach and by thermal sublimation under high vacuum(.) Samples were characterized by high-frequency electron spin resonance (HF-ESR), XPS, Raman spectroscopy, atomic force microscopy (AFM), and optical microscopy, supported with density functional theory (DFT) and complete active space self-consistent field (CASSCF)/N-electron valence second-order perturbation theory (NEVPT2) calculations. This compound's rationale is its structure, with several aromatic rings for weak binding and possible favorable pi-pi stacking onto graphene. In contrast to expectations, we observed the formation of nanodroplets on graphene for a drop-cast sample and microcrystallites localized at grain boundaries and defects after thermal sublimation
[Cu(X-salicylato)2(N,N-diethylnicotinamide)2(H2O)2] complexes: conformational polymorphism and its consequence in supramolecular hydrogen-bonding networks formation
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