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41.
Two new coordination polymers, [Ag2(barb)(pipet)]n (1) and {Na3[Ag2(barb)2](pippr)·2H2O}n (2) (where H2barb, pipet and Hpippr are 5,5-diethylbarbituric acid, N-piperidineethanol and 1,3-bis(4-piperidyl)propane, respectively) have been synthesized and characterized by elemental analysis, IR, thermal analysis and X-ray single-crystal diffraction techniques. Silver(I) ions in complexes 1 and 2 are bridged by barb dianions, leading to one-dimensional coordination polymers. In 1, the barb ligand acts as a tetradentate bridging ligand, while in 2 as a bidendate bridging ligand. The pipet ligand behaves as a bidentate chelating donor, whereas the pippr anion is not involved in coordination and remains as a counter-ion. The one-dimensional chains of 1 and 2 are further extended into supramolecular networks. Spectral and thermal analysis data for 1 and 2 are in agreement with the crystal structures. 相似文献
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The reaction of silver(I) with 1,2-bis[1-(pyridin-2-yl)ethylidene]hydrazine (bpeh) and N,N-bis(pyridin-2-ylmethyl)amine (bpma) in the presence of Na(sac) (sac = saccharinate) yielded [Ag2(sac)2(bpeh)] (1) and [Ag(sac)(bpma)]n (2) with conformational chirality. Both complexes have been characterized by elemental analysis, IR, thermal analysis and X-ray single crystal diffraction. Complex 1 displays a binuclear composition, in which each silver(I) ion is bound to one monodentate sac ligand and one of the bidentate pyridylimino groups of the bpeh ligand in a distorted trigonal coordination geometry. Complex 2 is a one-dimensional helical polymer, in which silver(I) centers are bridged by tridentate bpma ligands, and each silver(I) ion is coordinated in a distorted tetrahedral geometry by one monodentate sac ligand, a bidentate pyridylamine group of one bpma ligand, and a py group of another bpma ligand. Weak intermolecular C–H?O hydrogen bonds and C–H?π interactions lead to assembly of 1 and 2 into three-dimensional supramolecular frameworks. Spectral and thermal analysis data for 1 and 2 are in agreement with the crystal structures. In addition, both complexes in the solid state display intraligand π–π∗ fluorescence. 相似文献
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Homa Sadeghzadeh Ali Morsali Veysel T. Yilmaz Orhan Büyükgüng?r 《Ultrasonics sonochemistry》2010,17(3):592-597
Nano-structures of two new lead(II) two-dimensional coordination polymers, [Pb2(2-pyc)2(I)2]n (1) and [Pb2(2-pyc)2(Br)2]n (2), {2-Hpyc = 2-pyridinecarboxilic acid } were synthesized by a sonochemical method that produce the coordination polymers at nano-size. The new nano-structures were characterized by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy and elemental analyses. Compounds 1 and 2 were structurally characterized by single crystal X-ray diffraction and consist of two-dimensional polymeric units. The thermal stability of compounds 1 and 2 were studied by thermal gravimetric and differential thermal analyses. PbO and PbBr(OH) nano-structures were obtained by calcination of the nano-structures of compounds 1 and 2 at 400 °C, respectively. 相似文献
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Ali Veysel Tunc Bernhard Ecker Zekeriya Dogruyol Sabrina Jüchter Ahmet Lütfi Ugur Ali Erdogmus Sait Eren San Jürgen Parisi Elizabeth von Hauff 《Journal of Polymer Science.Polymer Physics》2012,50(2):117-124
In this study, we demonstrate how the intrinsic properties of a polymer can influence the electrical characteristics of organic field‐effect transistors (OFETs). OFETs fabricated with three batches of poly[2‐methoxy,5‐(3′,7′‐dimethyl‐octyloxy)]‐p‐phenylene vinylene (MDMO‐PPV) were investigated. The properties of the polymers were initially investigated using Fourier transform infrared spectroscopy (FTIR), impedance spectroscopy (IS), gel permeation chromotography (GPC), and cyclic voltammetry (CV), respectively. The structure and purity of the polymer batches were found to be very comparable, but the molecular weight (Mn and Mw) and polydispersity (PDI = Mw/Mn), varied between the samples and the HOMO and LUMO levels of the polymers were found to depend on the molecular weight properties. OFETs were then fabricated with the polymers and electrically characterized. It was observed that the channel current and the field‐effect mobility increase with increasing polymer molecular weight. The output characteristics of the transistors, on the other hand, were found to depend on the PDI of the polymer. Saturation of the channel current occurs at higher source–drain voltages and short‐channel behavior was observed to start at longer channel lengths for polymers with a higher PDI. This behavior is observed to be thickness dependent, and the short‐channel behavior was more pronounced for thicker MDMO‐PPV films. These results are explained in terms of influences of chain packing and ordering and high bulk currents on the FET output and transistor parameters. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 50: 117–124, 2012 相似文献
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Veysel T. Yilmaz Canan Kazak Erbil Aar Bahittin Kahveci Kutalmis Guven 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(2):o101-o104
The title compounds, 4‐benzylamino‐3‐(4‐methylbenzyl)‐1H‐1,2,4‐triazol‐5(4H)‐one, C17H18N4O, (I), 3‐(4‐methylbenzyl)‐4‐(4‐methylbenzylamino)‐1H‐1,2,4‐triazol‐5(4H)‐one, C18H20N4O, (II), and 3‐(4‐chlorobenzyl)‐4‐(4‐methylbenzylamino)‐1H‐1,2,4‐triazol‐5(4H)‐one, C17H17ClN4O, (III), were obtained from the corresponding Schiff base in the presence of diglyme and NaBH4. Each compound contains a 1,2,4‐triazole ring and two benzene rings, which are essentially planar. The molecules are linked by a combination of intermolecular N—H⋯O and N—H⋯N hydrogen bonds. Additionally, there is a weak π–π stacking interaction in (I), involving the benzene ring of the aminobenzyl group and the partially aromatic 1,2,4‐triazole moiety, with a centroid–centroid distance of 3.7397 (10) Å. 相似文献
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New lead(II)‐saccharin complexes, [Pb(sac)2(pym)] (1) and [Pb(sac)2(pydm)] (2) (sac = saccharinate anion; pym = 2‐pyridylmethanol; pydm = pyridine‐2, 6‐dimethanol) were synthesized and characterized by IR spectroscopy and single crystal X‐ray diffractometry. Complex 1 crystallizes in the monoclinic P21/c space group with Z = 4, while the crystals of complex 2 are extremely X‐ray sensitive and decompose by the X‐ray beam within one day. Pym and pydm act as bi‐ and tridentate ligands, respectively. Most important feature of the complexes is non‐equivalent coordination of the sac ligands to the lead(II) atom. In the complex 1 , the sac ligands coordinate to the lead(II) ion in two distinct manners. One sac ligand behaves as a bridge between the lead(II) atoms through its N and carbonyl O atoms, whereas the other sac ligand acts as a bidentate chelating ligand through its N and carbonyl O atoms which is bicoordinating and also bridges the metal atoms to achieve the seven‐coordination. The structure is built up of three‐dimensional chains formed by the bridging of the PbN3O2 units and also held intermolecular hydrogen bonds. The IR spectra of the complexes were discussed in detail. 相似文献
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Veysel T. Yilmaz Turan K. Yazicilar Omer Andac Halil Kutuk Yunus Bekdemir William T. A. Harrison 《无机化学与普通化学杂志》2002,628(8):1908-1912
The reaction of sodium benzoxasulfamate (nbs) with cadmium(II) and mercury(II) sulfate in aqueous solution yield the novel complexes [Cd(nbs)2(H2O)4] (1) and [Hg(nbs)2(H2O)3] ( 2 ), respectively. The complexes were characterized by elemental analyses, IR spectroscopy and X‐ray crystallography. Complex 1 is monomeric and has an octahedral arrangement in which the N‐donor nbs ligands occupy the axial positions, while the water oxygen atoms form the equatorial plane. Complex 2 is polymeric and shows a pentagonal bipyramidal arrangement achieved by the bridging of the HgN2O3 units through the weak interaction of the O atoms of the nitro group. The nbs ligands also occupy the axial positions of the pentagonal bipyramid, whereas three water and two nitro oxygen atoms constitute the pentagonal plane. The crystal structure packing in both crystals is achieved by the intermolecular hydrogen bonds involving water hydrogen atoms, nitro and sulfonyl oxygen atoms. 相似文献