68 research outputs found
An iron(II) complex of trans, trans, trans-bis(azido)bis(4-amino-3,5-bis(2-pyridyl)-1,2,4-triazole): insight into molecular and supramolecular structures using hirshfeld surface analysis and DFT studies
No full textThe solvothermal synthesis and structural characterization of the new high-spin iron(II) complex trans,trans,trans-[bis(azido)bis(4-amino-3,5-bis(2-pyridyl)-1,2,4-triazole)iron(II)] is reported. The complex crystallizes in the triclinic space group Pī with Z = 1, a = 6.6648(3) Å, b = 8.4012(3) Å, c = 11.7970(5) Å, α = 85.063(2)°, β = 95.063(2)°, γ = 98.5080(10)°. It is centrosymmetric with mutually trans pairs of azido, pyridyl and triazole N atoms, the Fe–N distances indicate a high-spin configuration. A combination of N–H···N hydrogen bonds and π···π stacking interactions generates a sheet structure in which the shortest Fe···Fe distance is 6.6648(3) Å. Hirshfeld surface analysis has been performed for visualizing, exploring and quantifying intermolecular interactions that stabilize the crystal packing of the complex. Non-covalent interactions present in the crystal structure have also been analysed by means of computational tools. The interaction energies associated with the different interaction topologies were calculated and QTAIM and NBO analyses were applied to study the origin and nature of the attractive forces.Fil: Setifi, Zouaoui. Université Ferhat Abbas; ArgeliaFil: Setifi, Fatima. Université Ferhat Abbas; ArgeliaFil: Glidewell, Christopher. University of St. Andrews; Reino UnidoFil: Gil, Diego Mauricio. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; ArgentinaFil: Kletskov, Alexey V.. University of Russia; RusiaFil: Echeverria, Jorge. Universidad de Barcelona; EspañaFil: Mirzaei, Masoud. University of Mashhad; Irá
A combined experimental, Hirshfeld surface analysis, and theoretical study on fac-[tri(azido)(tris(2-pyridyl)amine)iron(III)]
No full textA novel Fe(III) complex with the general formula [Fe(tpa)(N3)3] (1) (tpa = tris(2-pyridyl)amine), has been prepared by solvothermal synthesis and characterized by standard spectroscopic and analytical methods to determine its composition. Crystal structure analysis at 170 K shows that the tris(2-pyridyl)amine ligand is coordinated in tridentate fashion via the pyridyl N atoms and the complex as a whole has approximate threefold rotational symmetry: the Fe–N distances indicate that the metal centre adopts a low-spin configuration at 170 K. A combination of two C-H···N hydrogen bonds and two azido···π(pyridyl) interactions link the molecules into a continuous three-dimensional array. An analysis of the complex total energy evaluated the preference of the high-, intermediate- and low-spin complexes. DFT calculations showed that the high-spin complex is the least energetic of the three possible spin states. The Quantum Theory of Atoms In Molecules (QTAIM), Reduced Density Gradient (RDG), and Natural Bond Orbitals (NBO) analysis showed an azido···azido interactions cooperatively assisted by weak hydrogen bonds and lone-pair···π interactions between N3– and the pyridine fragment from the tris(2-pyridyl)amine ligand. The amine and N3– arrange to bear a caged anion. The azido···azido interaction nature can be related to the donation from the N lone-pair to the π* of the opposite anion.Fil: Setifi, Zouaoui. Université 20 Août 1955-Skikda; Argelia. Université Ferhat Abbas Sétif 1; ArgeliaFil: Cubillán, Néstor. Universidad del Atlántico; ColombiaFil: Glidewell, Christopher. University of St. Andrews; Reino UnidoFil: Gil, Diego Mauricio. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; ArgentinaFil: Torabi, Elham. Ferdowsi University Of Mashhad; IránFil: Morales Toyo, Miguel. Universidad Central del Este; República DominicanaFil: Dege, Necmi. Ondokuz Mayıs University; TurquíaFil: Setifi, Fatima. Université Ferhat Abbas Sétif 1; ArgeliaFil: Mirzaei, Masoud. Ferdowsi University Of Mashhad; Irá
The synthesis, characterization, X-ray structure and magnetism of dinuclear-based bis[μ-(1,1,3,3-tetracyano-2-ethoxypropenido-κ2N,N′) (1,1,3,3-tetracyano-2-ethoxypropenido-κN)(2,2′-bipyridine)copper(II)] organized in alternating chains via semi-coordinating Cu–N distances
No full textThe monoanionic ligand 1,1,3,3 tetracyano-2 ethoxypropenide (tcnoet) is reported with its Cu(II)–bpy complex of formula [Cu2(µ-tcnoet)2(tcnoet)2(bpy)2]. The structure has been determined using X-ray diffraction and features an alternating chain with bridging tcnoet ligands. One ligand acts as a bidentate, dinucleating ligand with one short Cu–N and one medium Cu–N bond, whereas the other tcnoet is largely monodentate, albeit with a very weak interdimer Cu–N bond. Despite the arrangement in dinuclear units, further arranged into linear chains through the non-bridging tcnoet ligand, the compound shows no significant magnetic exchange, as deduced from magnetic susceptibility down to 4 K. Ligand-field, IR and EPR spectra in the solid state and in frozen solution are reported and are consistent with the overall structure
(Adipato-κ2O,O′)diaqua[bis(pyridin-2-yl-κN)amine]cobalt(II) trihydrate
No full textIn the monomeric title complex, [Co(C6H8O4)(C10H9N3)(H2O)2]·3H2O, the distorted octahedral CoN2O4 coordination environment comprises two N-atom donors from the bidentate dipyridyldiamine ligand, two O-atom donors from one of the carboxylate groups of the bidentate chelating adipate ligand and two water molecules. In addition, there are three solvent water molecules which are involved in both intra- and inter-unit O—H...O hydrogen-bonding interactions, which together with an amine–water N—H...O hydrogen bond produce a three-dimensional framework
Functional ligand designs for the elaboration of magnetic networks based on iron, cobalt or rare earth ions
No full textL’objectif de cette thèse porte sur la conception de nouveaux composés de coordination à partir de ligands imidazolium fonctionnalisés par différentes fonctions de coordination ou de ligands dérivés du motif 1,2,4-triazole et de cations de transition tels que les ions Fe2+ ou Co2+ ou d’ions lanthanides tels que les ions Dy3+. Le but de ces associations est de générer des réseaux fonctionnels pouvant présenter des propriétés magnétiques voire de luminescence. Plusieurs méthodes de synthèse ont été utilisées pour obtenir ces composés : méthode solvothermale, méthode de diffusion ou encore modification post-synthèse lorsque les méthodes directes ne marchaient pas. La mise en oeuvre de ces différentes méthodologies a permis d’obtenir plusieurs composés qui ont été caractérisés structuralement, spectrocopiquement et magnétiquement en exploitant différentes techniques telles que la diffraction de rayons X, la spectroscopie infrarouge et UV-Visible, la microscopie électronique à balayage, les analyses thermiques et élémentaires ou encore la spectroscopie de photoélectrons et la magnétométrie à SQUID.The aim of this thesis is to progress in the design of new coordination networks using imidazolium ligands functionalized with different coordination functions or ligands based on 1,2,4-triazole and transition metals such as Fe2+ or Co2+ or lanthanide ions such as Dy3+. The goal is to generate magnetic and even luminescent networks. Several synthesis strategies have been used to obtain these compounds : solvothermal and non-solvothermal reactions and post-synthesis modifications when direct reactions were not efficient. The use of these strategies has led to several compounds for which structural characterization have been performed using X ray diffraction. Analysis such as infrared and UV-Visible spectroscopies, scanning electronic microscope, thermal and elementary analysis end even X-ray photoelectron spectroscopy as well as SQUID magnetometry have been carried out to fully characterized all these compounds
Synthèse, structures et propriétés physiques de matériaux moléculaires conducteurs et magnétiques
No full textCe travail concerne la synthèse, les études structurales par diffraction des rayons X et l'étude des propriétés électriques et magnétiques de matériaux moléculaires à propriétés multiples, associant en particulier conductivité électrique et interactions magnétiques. Ces composés sont formés de donneurs organiques dérivés du tétrathiafulvalène (TTF) ou du tétrathiapentalène (TTP) et de complexes anioniques d'ions de transition. Afin d'établir des interactions entre les électrons mobiles de la partie organique conductrice et les spins localisés de la partie inorganique paramagnétique, trois types de stratégies sont étudiés (i) l'utilisation de donneurs fonctionnalisés, (ii) l'utilisation d'anion dont les ligands possèdent des systèmes pi et (iii) la synthèse de nouveaux complexes de coordination où les systèmes conducteurs et magnétiques sont liés par un pont conjugué.RENNES1-BU Sciences Philo (352382102) / SudocSudocFranceF
Bis{bis(azido-κN)bis[bis(pyridin-2-yl-κN)amine]cobalt(III)} sulfate dihydrate
No full textThe search for new molecular materials with interesting magnetic properties, using the pseudohalide azide ion and di-2-pyridylamine (dpa, C10H9N3) as a chelating ligand, led to the synthesis and structure determination of the title compound, [Co(N3)2(dpa)2]2SO4·2H2O. The crystal structure comprises discrete [Co(dpa)2(N3)2]+ cations, sulfate anions, as well as H2O solvent molecules. The CoIII cations display a slightly distorted octahedral coordination sphere defined by two N atoms from azide anions and four N atoms from the pyridyl rings of two dpa ligands. In the crystal, extensive C—H...O, N—H...O, and O—H...O interactions result in supramolecular sheets that lie parallel to the ab plane. The sheets are further linked through O—H...N interactions between the water molecules of one sheet and azide anions of another sheet, forming a supramolecular framework
Crystal structure of [tris(4,4′-bipyridine)]diium bis(1,1,3,3-tetracyano-2-ethoxypropenide) trihydrate
No full textThe authors acknowledge the Algerian MESRS (Ministère de l'Enseignement Supérieur et de la Recherche Scientifique), the DGRSDT (Direction Générale de la Recherche Scientifique et du Développement Technologique) and Université Ferhat Abbas Sétif 1 for financial support.The title hydrated salt, C30H26N62+·2C9H5N4O−·3H2O, was obtained as an unexpected product from the hydrothermal reaction between potassium 1,1,3,3-tetracyano-2-ethoxypropenide, 4,4′-bipyridine and iron(II) sulfate heptahydrate. The cation lies across a twofold rotation axis in the space group I2/a with the other components all in general positions. In the cation, the H atom linking the pyridine units is disordered over two adjacent sites having occupancies of 0.66 (4) and 0.36 (4), i.e. as N—H⋯N and N⋯H—N. The water molecules of crystallization are each disordered over two sets of atomic sites, having occupancies of 0.522 (6) and 0.478 (6) for one, and 0.34 (3) and 0.16 (3) for the other, and it was not possible to reliably locate the H atoms associated with these partial-occupancy sites. In the crystal, four independent C—H⋯N hydrogen bonds link the ionic components into a three-dimensional network.Peer reviewe
Synthesis, structure, and magnetic properties of a dinuclear antiferromagnetically coupled iron(II) complex
No full textThe authors acknowledge the Algerian DGRSDT (Direction Générale de la Recherche Scientifique et du Développement Technologique) and Université Ferhat Abbas Sétif 1 for financial support.A new dinuclear Fe(II) complex with the general formula [Fe2(1,4-tpbd)(dca)4(H2O)2] ( 1 ) (in which 1,4-tpbd = N,N,N′,N′-tetrakis(2-pyridylmethyl)benzene-1,4-diamine; dca = dicyanamide, [N(CN)2]−), has been prepared under hydrothermal conditions and fully characterized by elemental analysis, infrared spectroscopy, X-ray diffraction, and magnetic measurements. The compound crystallizes in the triclinic system and P-1 space group with Z = 1 and the following unit cell parameters: a = 8.165(5) Å, b = 10.236(5) Å, c = 13.105(5) Å, α = 81.421(5)°, β = 78.810(5)°, γ = 72.941(5)°, and V = 1022.2(9) Å3. The Fe(II) ions are six-coordinated, in distorted octahedral fashion, by three N atoms of tpbd ligand, one water oxygen atom and two N atoms of two dicyanamide anions. The intra-dinuclear Fe⋯Fe distance via the bridged μ2-tpbd ligand is 8.293(8) Å. In the molecular arrangement, the combination of OH⋯N and CH⋯N hydrogen bonds links the title complex to form a three-dimensional supramolecular structure. Magnetic susceptibility measurements (2–300 K) show that 1 presents weak antiferromagnetic exchange between the two nearest Fe2+ ions with the coupling constant J = −1.05 cm−1.Peer reviewe
Redetermination of the crystal structure of bis(tri-2-pyridylamine)iron(II) bis(perchlorate), and a new refinement of the isotypic nickel(II) analogue: treatment of the perchlorate anion disorder
No full textThe redetermination of the structure of the title compound, [Fe(C15H12N4)2](ClO4)2, (I), confirms the structure previously reported [Kucharski et al. (1978a). Aust. J. Chem. 31, 53–56], but models the perchlorate over four sets of atomic sites, rather than using just one set of sites as in the original report. The supramolecular assembly, not reported previously, takes the form of a complex three-dimensional framework built from C—H...O hydrogen bonds. The isotypic nickel(II) analogue, [Ni(C15H12N4)2](ClO4)2, (III), has been refined using the original data set [Wang et al. (2011). Acta Cryst. E67, m78], again using a four-component disorder model for the anion, rather than a two-component model as in the original report, leading to more satisfactory Cl—O distances and O—Cl—O angles
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