Search

A new cyano-bridged binuclear 4f-3d complex Sm(DMSO)4-(H2O)3Cr(CN)6 was synthesized and characterized by single crystal structure analysis. It crystallizes in monoclinic, space group P21 with a=0.9367(2) nm, b = 1.3917(3) nm, c = 1.1212(2) run, β = 99.88(3)° and Z = 2. In this binuclear complex, Sm atom is eight coordinated and linked to the Cr atom by a cyano bridge. The molecules packs to form 3D structure due to the hydrogen bonds among them. [K3(18-C-6)3(H2O)4]Cr(CN)6·3H2O (18-C-6 represents 18-crown-6-ether) that was synthesized as a byproduct in the preparation of a Gd—Cr complex is also structurally characterized. Crystal data: triclinic, space group P-l with a = 1.0496(7) nm, b= 1.1567(14) nm, c = 1.3530(13) nm, a = 94.15(9)°, β = 96.04(8)°, γ = 95.25(9)° and Z = l. [K3(18-C-6)3(H2O)4]-Cr(CN)6·3H2O consists of ionic [K3(18-C-6)3(H2O)4]3+ and [Cr(CN)6]3- pairs, of which the [K3(18-C-6)3(H2O)4]3+ ion is a trinuclear duster connected by water, and K atoms are eight coordinated by eight oxygen atoms of one 18-C-6 and two water molecules.

A novel inorganic-organic hybrid material, Fe2O(OH)(C5H4-NCOO)SO4 was synthesized via solvothermal route using a reaction of FeCl3 ·6H2O, KCNS, and 4-cyanopyridne in aqueous solution of H2O2 and ethanol at 130 °C for 3 d. The compound crystallized in monoclinic space group P21, with cell parameters a=0.73850(15) nm, b = 0.65100(13) mn, c = 1.0546(2) nm, β = 90.36(3)°, V = 0.50700(18) nm3 and Z = 2. The structure is constructed with inorganic layered [Fe2O(OH) SO4]+ cations linked by organic (C5H4NCOO)− anions. The compound is thermally stable up to approximately 240 °C.

The complex Eu(btfa)3 (phen) (btfa=4,4,4-trifluoro-1-phenyl-1, 3-butanedione, phen = 1,10-phenanthroline) has been prepared and characterized by elemental analysis, IR and UV spectroscopies. The crystal and molecular structures of the complex have been determined by X-ray diffraction analysis. It belongs to the monoclinic crystal system, space group P21/c with a = 0.9700(2) nm, b = 3.7450(5) nm, c = 1.0917(3) nm, β = 92.51(2)°, V = 3.962(1) nm5, Z = 4, Dc = 1.639 g/cm3, μ = 1.676 mm−1, F(000) = 1936, R1, = 0.0388, wR2 = 0.0775. Structure analysis shows that the europium(III) ion is coordinated to six oxygen atoms of β-diketonate anions and two nitrogen atoms of phenanthroline molecule. The coordination polyhedron is an approximate square antiprism.

Twenty new compounds of the form Ph3GeCHArCH2COOSnR3 (R = n-Bu, cyclohexyl; Ar = substituted phenyl) have been synthesized. Their structures were characterized by IR and 119Sn and 1H NMR spectroscopy. The compounds are five-coordinated carboxylate bridged polymers when R = n– Bu; when R = cyclohexyl (Cy) they are four-coordinate. 119Sn NMR measurements of chemical shift for the two series of compounds have shown that there is a good linear relationship for the chemical shift of 119Sn NMR between the tributyltin and tricyclohexyltin propionates, viz. δ119Sn(Bu3Sn) = 1.0474 δ 119Sn(Cy3Sn) + 95.8076, n = 5, r = 0.993. The structure of one compound was determined by X-ray diffraction. It exists as a monomeric four-coordinated species in a distorted tetrahedronal geometry.

Crystalline [Dy(NCS)3(dibenzo-30-crown-10)(H2O)2]·H2O·MeCN can be obtained by slowly evaporating a reaction mixture of Dy(NCS)3·nH2O with dibenzo-30-crown-10 in a solution of acetonitrile. The material crystallizes in the monoclinic space groupP21/n, the cell parameters area=11.450(5),b=23.284(4),c=18.424(6)A, β=106.28(4)°,V=4715A3,M=968.47,D x=1.36 g cm−1, μ=17.80 cm−1,F(000)=1972,Z=4.2740 independently observed [I≥3σI] reflections were used in the final least-squares refinement leading to an agreement index ofR=0.085. The Dy(III) ion coordination geometry approximates a square antiprism, involving two water oxygens and three dibenzo-30-crown-10 oxygen atoms and three isthiocyanate nitrogens. Hydrogen bonds are formed between the two water molecules and four uncoordinated crown ether oxygen atoms.

The title compound has been synthesized and its crystal structure determined by X-ray crystallographic method. The crystal is monoclinic, space group C2/c, with unit cell dimensions a=19.260 (3), b=11.217 (1), c=15.997 (1) A; β=92.08 (2)° and Z=8. This is the first crystal structure determined in the series of bicyclo[10.3.0]pentadec-1(12)-en-13-one derivatives. The structure and the conformation of the cis-cyclododecene moiety in this compound is demonstrated to be closely similar to the lowest energy conformer [lene 2333].

The isomorphous cadmium(II) oxalate trihydrate (I) and lead(II) oxalate trihydrate (II) crystals belong to space groupP¯1 withZ=2. The crystallographic parameters for compoundI are:a=6.006(1),b=6.663(1),c=8.497(1)A,a=74.76(1),β=74.39(1), γ=80.94(1)°, andR=0.028 for 2643 observed MoKα reflections; forII:a=6.008(1),b=6.671(1),c=8.493(1)A,a=74.70(1),β=74.33(1), γ=80.98(1)°, andR=0.065 for 4536 reflections. In the crystal structure, the metal atom is surrounded by seven oxygen atoms (including two aqua ligands) in the form of a distorted pentagonal bipyramid. The coordination polyhedra are interconnected through bridging oxalate groups to form a “thick layer” matching the (020) plane. Adjacent layers are further linked by hydrogen bonds involving both ligand and lattice water molecules to generate a three-dimensional network.

The effects of different surfactants on Hf-quercetin, Zr-quercetin, Sn-morin, Mg-oxine-5-sulfonic acid (H_2QS), Zn-H_2QS, Cd-H_2QS and Tb-EDTA-sulfosalicylic acid (SSA) systems were investigated. It was found that the fluorescence intensity of each complex studied is increased greatly in the presence of a suitable surfactant. The optimum conditions of formation of the ternary complexes involving a surfactant were found, and the compositions of these ternary complexes were established by fluorometry. In the presence or absence of a surfactant, the quantum efficiencies (φ) of fluorescent complexes were measured by relative method, and their molar absorptivities at the excitation wavelength (e_(ex)) wore calculated. It was found that the quantum efficiencies and molar absorptivities of fluorescent complexes were increased to various degrees due to the formation of the ionic associated complexes with fixed composition, and their fluorescence intensity was increased greatly thereby. The function of surfactant micellar and the relation between the molecular structures of surfactants and their effects on the fluorescent reactions were discussed. It is noted that only by the surfactants in the molecule of which the aromatic system is not charged or connected directly with a charged functional group can the fluorescent reactions be sensitized. With the sensitization of surfactant it is possible to develop some fluorometries of metals which are highly sensitive.

The crystal and molecular structure of the complex containing cobalt-carbon and iron-sulfur cluster cores, (μ-p-CH3C6H4C2S) (μ-n-C3H7S)Fe2(CO)6Co2(CO)6, has been determined by X-ray diffraction method. The crystals are triclinic, space group P&1bar;, with a — 9.139(2), b=9.610(1), c-17.183(2) A, α = 84.36(1), β-89.45(1), γ=88.15(1)°, V-1501.0 A3; Z=2, Dc=1.74 g/cm3. R=0.072, Rw=0.081. The results of the structure determination show a cobalt-carbon cluster core formed through the reaction of (μ-p-CH3C6H4C2S)(μ-n-C3H7S)Fe2(CO)6 with Co2(CO)8. In the cobalt-carbon cluster core, the bond length of the original C≡C lengthened to 1.324 A which is close to the typical value of carbon-carbon double bond. The groups connecting the carbons of the cluster core are in cis position and lie on the opposite side of cobalt atoms. In this complex, the conformation of —SC3H7 is e-type, while that of —SC2C6H4CH3 is a-type.