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531.
A donor–acceptor compound, di­aqua‐1κO,2κO‐[μ‐11,23‐dimethyl‐3,7,15,19‐tetra­aza­tri­cyclo­[19.3.1.19,13]hexacosa‐1(25),2,7,9,11,13(26),14,19,21,23‐decaene‐25,­26‐diolato‐1κ4N3,N7,O25,O26:­2κ4N15,N19,O25,O26]­dizinc(II) diperchlorate bis(8‐methyl­quinoline) ethanol disolvate, [Zn2(C24H26N4O2)(H2O)2](ClO4)2·2C10H9N·2C2H6O, obtained by the reaction of a dinuclear zinc(II) complex of a Robson macrocycle (acceptor) and 8‐methyl­quinoline (donor), lies about an inversion centre and the coordination about the unique Zn atom is a distorted square pyramid. The fifth coordination site is occupied by the water mol­ecule, Zn—O = 2.016 (2) Å, and the average macrocyclic Zn—O and Zn—N distances are 2.059 (6) and 2.059 (3) Å, respectively.  相似文献   
532.
Results of a single-crystal X-ray diffraction study of the complex of zinc(II) acetate with 2-amino-5-ethyl-1,3,4-thiadiazole were presented. The coordination polyhedron of the complex has a distorted tetrahedral configuration with nitrogen atoms of the two 2-amino-5-ethyl-1,3,4-thiadiazole molecules and oxygen atoms of the two acetate ions coordinated to the central ion.  相似文献   
533.
The short carbonyl bond in the title compound, [Cu2(C7H4­NO3S)4(C3H4N2)4] [Liu, Huang, Li & Lin (1991). Acta Cryst. C 47 , 41–43], is an artifact of disorder in the iso­thia­zol‐3(2H)‐one 1,1‐dioxide part of the 1,2‐benziso­thia­zol‐3(2H)‐one entity. In the present redetermination, all bond dimensions in the centrosymmetric dinuclear mol­ecule are normal. The five‐coordinate Cu atom shows trigonal–bipyramidal coordination. Hydro­gen bonds from the imidazole donor ligand link adjacent mol­ecules into a two‐dimensional layer structure.  相似文献   
534.
制备4,4-连吡啶基二卤加和物[MX2(4,4′-bipy)]n仍然有较大困难.这类化合物数量不多且已报道的多为难处理的微晶材料.本文在室温下通过简单的操作合成了新的碘化汞连吡啶乙烷加和物[HgI2(bpea)]nox-射线单晶衍射分析表明其中的汞原子通过与两个碘原子以及吡啶乙烷的两个氮原子配位形成扭曲的四面体构型.每个HgI2单元由bpea桥连形成锯齿状链.其非线性光学性质用8-纳秒激光在532nm波长进行了研究.该化合物相对于入射光表现为一定的光学吸收和强的自聚焦效应,其三阶非线性吸收系数α2=1.1×10-11m@W-1,折射系数n2=5.29×10-188m2@w-1.  相似文献   
535.
A ratiometric fluorescent turn-on probe for fluoride ion, based on modulation of the excited-state intramolecular proton transfer (ESIPT) process by chemodosimetric desilylation pathway is reported. The probe SNBT (silyl protected hydroxynaphthalene benzothiazole moiety) shows a significant increase of ratiometric absorption band at 440 nm and emission band at 477 nm by the deprotection of fluoride mediated silyl bond cleavage in CH3CN–H2O (8/2, v/v, 25 °C). The test strips based on SNBT and F are fabricated, which can act as a convenient and efficient F test kits. Furthermore, the biological application shows that it can be very useful as a selective fluoride probe in the fluorescence imaging of living cells.  相似文献   
536.
537.
In the title complex, [RuCl2(C16H36N4)]I3, the overall symmetry of the centrosymmetric cation is approximately C2h and the I anions are slightly asymmetric. The I?I distance is 4.313 (1) Å. The cations and the linear anions are arranged in alternate layers and thus form the intercalating structure.  相似文献   
538.
The spectral studies and structure of a ternary complex of copper(II) with 2-hydroxyacetophenone 3-hexamethyliminylthiosemicarbazonate (L(2-)) and 1,10-phenanthroline (phen) are reported. The thiosemicarbazone binds to the metal as a dianionic ONS-donor (L(2-)) ligand, and forms a complex of the stoichiometry [CuLphen]. The copper(II) complex was characterized by IR and UV/Vis spectroscopies, as well as by solid state room-temperature magnetic susceptibility. Spin Hamiltonian and bonding parameters of the compound are calculated from the EPR spectra. Computer simulation of EPR spectrum in DMF at 77 K aided the calculation of magnetic and bonding parameters of the compound. The structure of the compound is solved by single crystal X-ray diffraction. The geometry around copper is distorted square pyramidal.  相似文献   
539.
The title complex [Mn2(phen)4(FCA)2](ClO4)2·H2O (1) (FCA = dianion of 3-ferrocenyl-2-crotonic acid, phen = 1,10-phenanthroline) has been prepared, and its structure determined by single crystal X-ray diffraction analysis. The structure consists of a dinuclear cation [Mn2(phen)4(FCA)2]2+, non-coordinated perchlorate anions and a water molecule. The two MnII ions are separated by 4.374 Å in the cation and are dicarboxylate-bridged by carboxylate ligands containing ferrocenyl units. Each FCA is bound to two MnII ions through carboxylate oxygens with the synanti bridging mode. The MnII ion is coordinated in an octahedral N4O2 geometry by two chelate phen ligands and two -carboxylate oxygen atoms. Electrochemical properties of (1) are discussed.  相似文献   
540.
Three polymeric silver(I) complexes with terephthalate anions as counterions or ligands, [Ag(pren)]2(tp)·2H2O ( 1 ), [Ag(en)][Ag(μ2‐tp)]·H2O ( 2 ), and [Ag2(μ4‐tp)(apy)2] ( 3 ) (where pren = 1, 2‐propylenediamine, tp =terephthalate dianion, en = ethylenediamine, and apy = 2‐aminopyridine) were synthesized and characterized by X‐ray single crystal analysis and infrared spectroscopy. 1 crystallizes in the monoclinic space group P211/c with a = 11.3221(5), b = 7.1522(3), c = 14.8128(5)Å, V = 1015.77(7)Å3, β = 122.132(2), and Z = 2. 2 crystallizes in the orthorhombic space group Pnma with a = 9.6144(6), b = 11.3465(7), c = 11.4810(7)Å, V = 1252.5(1)Å3, and Z = 4. 3 crystallizes in the monoclinic space group P21/n with a = 8.2003(5), b = 5.8869(4), c = 18.3769(11)Å, β = 92.593(1), V = 886.2(1)Å3, and Z = 4. Terephthalate dianions are not coordinated to the metal atoms in 1 , but act as a μ2‐bridging ligand in 2 and as a μ4‐bridging ligand in 3 .  相似文献   
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