Synthesis and Structural Characterization of a New Cadmium(II) Complex with a Double Betaine

A new flexible double betaine L （L = 1,4-bis（pyridinio-4-carboxylato-N-methyl）benzene, C20H16N2O4） and its cadmium（Ⅱ） complex [Cd（H2O）aL（NO3）]NO3.H2O 1 were synthesized. Complex 1 was obtained by self-assembly reaction of [Cd（NO3）2]-4H2O and L in hot water,and its crystal structure was determined by single-crystal X-ray diffraction analysis. Crystallographic data for complex 1： C20H24CdN4O14.H2O, Mr = 674.85, monoclinic, space group P21/c, a =13.7854（3）, b = 14.2820（3）, c = 14.9188（4） ,A°, β = 116.418（1）°, V = 2630.5（1）A°^3, Z = 4, Dc= 1.704g/cm^3,/J（MoKα） = 0.911 mm^-1, F（000） = 1368, the final R = 0.0315 and wR = 0.0768 for 3637 observed reflections with I 〉 2σ（I）. In complex 1, L acts as a monodentate ligand to link a Cd（Ⅱ） ion in a novel coordination mode of double betaines. The mononuclear [Cd（H2O）aL（NO3）] units are connected through intermolecular hydrogen bonds and π-π stacking reactions to generate a 3D network.

Synthesis and Crystal Structure of a New Copper(II) Complex with 4-Cyanobenzoic Acid

A new Cu（Ⅱ） complex [Cu（4-cba）（1,10-phen）（H2O）2]（NO3） （4-Hcba = 4-cyanobenzoic acid） has been synthesized by solvothermal reaction in an ethanol/water mixed solution at 100 ℃ and structurally characterized by single-crystal X-ray diffraction. Crystallographic data： C20H16CuN4O7, Mr= 487.91, triclinic, space group PI, a = 7.8420（2）, b = 9.1070（2）, c = 15.1140（6） A, a = 76.889（9）, β = 81.332（11）, γ = 74.844（ 11）°, V = 1009.89（5） A^3, Z = 2, Dc = 1.605 g/cm^3, F（000） = 498, μ = 1.134 mm^-1, the final R = 0.0379 and wR = 0.0865 for 2977 observed reflections with 1 〉 2σ（Ⅰ）. The Cu（Ⅱ） atom is coordinated by two terminal water molecules, one chelating 1,10-phen molecule and one monodentate 4-cba ligand to form a slightly distorted square pyramid. The title complex molecules are connected through hydrogen bonds and π-π stacking interactions to generate a 2D layered network. The thermogravimetric analysis of the title complex has also been discussed.

Synthesis and Crystal Structure of a New Lanthanum(III) 4-Cyanobenzoate Complex

A new dinuclear La（Ⅲ） complex [La2（4-cba）4[H（4-cba）2]2（phen）2（H2O）4] （4-Hcba = 4-cyanobenzoic acid and phen = 1,10-phenanthroline） 1 has been synthesized by solvothermal reaction in an ethanol/water mixed solution at 100 ℃ and structurally characterized by singlecrystal X-ray diffraction. Crystallographic data： C88H58La2N12O20, Mr = 1881.28, triclinic P1, a = 7.518（3）, b = 17.033（6）, c = 17.551（6）A, α = 115.333（4）, β = 92.9910（10）, γ = 99.366（5）°, V = 1985.3（12）A^3, Z = 1, Dc = 1.574 g/cm^3, F（000） = 944 μ = 1.145 mm^–1, the final R = 0.0281 and wR = 0.0686 for 6708 reflections with Ⅰ 〉 2σ（I）. In 1, two nine-coordinated La（Ⅲ） ions are connected by two 4-cba ligands in a syn-syn bidentate coordination mode, and the other six 4-cba ligands terminate the La（Ⅲ） ions, resulting in an isolated dinuclear structure. Two different types of intramolecular hydrogen bonds, asymmetrical O-H…O and symmetrical O…H…O, exist in the crystal. The title complex molecules are connected through hydrogen bonds and weak π-π stacking interactions to generate a 2-D layered network. The thermogravimetric analysis of 1 has also been discussed.

Synthesis, Single-crystal Structure, and Optical and Magnetic Properties of CaEr_2S_4

Brown needle-like crystals of CaEr2S4 were isolated as the major product from a reaction of elements and binary sulfides by a two-step flux technique. CaEr2S4 crystallizes in the orthorhombic space group Pnma with a=12.845（4）, b=3.862（4）, c=13.001（2）（A）, V=645.0（7）（A）3,Z=4, F（000）=880,μ（MoKα）=27.794 mm^-1, the final R=0.0528 and wR=0.0562 for 1070observed reflections with I 〉 3σ（I）. The CaEr2S4 structure forms a three-dimensional framework that consists of interconnected tetra-octahedral Er4S18 fragments. Ca^2＋cations, in a monocapped trigonal prism geometry, are stuffed in two parallel rows into the one-dimensional channels along the b direction. CaEr2S4 is an infrared-transparent semiconductor with a band gap of 1.81 eV. Magnetic susceptibility measurements over 6～300 K indicate a Curie-Weiss paramagnetic behavior for the phase, with an effective magnetic moment of 9.64（1） μB per Er^3＋ ion.

Visible Light-induced Photoluminescence of a Zinc(Ⅱ) Complex of N-methyl-4,4-bipyridinium Cation

Compounds with visible-light-induced photoluminescence are particularly attractive in acting as the emitting components of light-emitting diodes and fluorescent probes for biological applications. A new complex [Zn(NCS)_3(MQ)](MQ^+ = N-methyl-4,4?-bipyridinium) with an isolated molecular structure has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy and solid-state photoluminescent determination. Crystal data: C_(14)H_(11)N_5S_3Zn, M_r = 410.83, monoclinic, space group P2_1/c, a = 8.809(5), b = 13.138(7), c = 15.580(9) ?, b = 104.433(10)°, V = 1746.2(17) ?~3, Z = 4, D–c = 1.563 g×cm^3, μ = 1.769 mm^(–1), F(000) = 832, the final R = 0.0376 and wR = 0.1243 for 2850 observed reflections with I > 2s(I). In the crystal structure, the zinc atom is tetrahedrally coordinated by one MQ+ ligand and three NCS– groups to yield a tetrahedral configuration. The bond length of Zn–NMQ is clearly shorter than those found in reported Zn(Ⅱ) complexes of 4,4?-bipy. The isolated units are joined by C–H···S interactions to generate a 2D hydrogen-bonding network. This compound displays visible light-induced photoluminescence, which originates from both intraligand charge-transfer of the MQ+ ligand and NCS~–→MQ^+ charge-transfer according to a density of states(DOS) calculation. Moreover, its emission band shows a clear blue shift compared with those of halide compounds.

Solid State Synthesis and Crystal Structure of K_3SI

A new ternary alkali metal chalcogenide halide, K3SI, has been synthesized by solid state reaction method and structurally characterized by X-ray crystallography. The crystal belongs to hexagonal, space group P63cm with a = 11.699（I ）, c = 5.8279（9） A°, Mr = 276.26, V = 690.8（1 ）A°^ 3, Z = 6, D, = 3.985 g/cm^3, F（000） = 756, μ = 9.913 mm^-1, S = 1.004, R = 0.0719 and wR = 0.2204. The title compound is the first example containing S anion in the ternary alkali metal chalcogenide halides family M3QX （M = alkali metal, Q = chalcogenide, X - halide）, which crystallizes in the hexagonal anti-perovskite structure type.

Synthesis,Crystal Structure and Magnetic Properties of the New Quaternary Thiophosphate Rb_2FeP_2S_6

A new quaternary thiophosphate Rb_2FeP_2S_6 was synthesized by the alkali metal halide flux method.The compound crystallizes in the monoclinic space group P2_1/c（No.14） with a = 6.042（3）,b = 12.338（6）,c = 9.045（4） ？,b = 124.25（2）°,V = 557.3（5） ？~3 and Z = 2.Its structure features 1-D infinite _∞~1[FeP_2S_6]^（2-） chains and counter cations Rb~＋.It shows a band gap of 2.03 eV.The nearest intra-chain Fe^（2＋） cations are antiferromagnetically coupled with each other,and there are weak ferromagnetic-like interactions between neighboring _∞1[FeP_2S_6]（2-） chains,resulting in two successive magnetic phase transitions.

Synthesis,Structural Characterization and Magnetic Properties of{[Gd(DMF)_(3)(DMSO)(H_(2)O)_(3)](μ-CN)(Fe)(CN)_(5)]}·2H_(2)O

A new cyano-bridged Gadolinium^(Ⅲ)-Iron^(Ⅲ)complex{[Gd(DMF)_(3)(DMSO)(H_(2)O)_(3)]2H_(2)0(DMF=N,N·-dimethylformamide;DMSO=dimethylsulfoxidel}was synthesized by the grinding reaction method,.It crysta-]llizes in the triclinic.,space group P1 with ceIl parameters:a=O.90363(2)nm,b=1.25078(3)nm,c=1.41303(1)nm,穋m^(-3),Z=2,Mr=756.72,F(000)=760,Ⅲ)and the approxi-mately oriented octahedrally sixfold-coordinated Fe(Ⅲ)are linked by a cyano-bridge group to construct a dinuclear compound.The{[Gd(DMF)_(3)(DMSO)(H_(2)O)_(3)](Ⅲ)-Fe(Ⅲ)interaction is antiferromagnetic.CCDC:223430.

Enhancing Electrochemical Reduction of CO_(2) to Formate by Regulating the Support Morphology

Electroreduction of CO_(2) to formic acid has attracted extensive attention,because it is a promising strategy to re-utilize CO_(2) and reduce greenhouse gas emissions that may favor the mitigation of energy and environment issues.Although great efforts have been made to tune the structure and composition of catalysts aiming to improve CO_(2) conversion efficiency,seldom studies have been focused on the support regulation.In this work,ordered,porous TiO_(2) nanotube arrays have been used as model support to study the impact of pore structure for CO_(2) electrochemical reduction.It has been revealed that Pd supported on TiO_(2) nanotube arrays substrate exhibits enhanced performance towards CO_(2) reduction,showing a higher formate Faradaic efficiency of 20%over than Pd supported on TiO_(2) film substrate.This study will shed new light on the design and synthesis of efficient catalysts by tuning the morphology of support for CO_(2) conversion.

Synthesis,Crystal Structure and Fluorescent Properties of New Layered Thiophosphate Cs_(2)Ga_(3)PS_(8)

A new quaternary metal thiophosphate,Cs_(2)Ga_(3)PS_(8),in triclinic P1^(-) space group has been successfully synthesized by a reactive-flux method.Its structural framework is derived from well-known AM^(Ⅲ)M^(Ⅳ)Q_(4) (A=alkali metal;M^(Ⅲ)=Al,Ga,In;M^(Ⅳ)=Si,Ge,Sn;Q=S,Se) system and composed of two-dimensional ^(2)∞[Ga_(3)PS_(8)]^(2-) layers separated by Cs^(+).The compound exhibits a wide band gap of 3.08 eV and congruent-melting behavior with melt point of 645℃.Interestingly,Cs_(2)Ga_(3)PS_(8) exhibits a broad photoluminescent emission band at 420 nm upon excitation at 295 nm.Moreover,electronic structure calculations indicate that Cs_(2)Ga_(3)PS_(8) is a direct band gap compound and its luminescent process can be mainly ascribed to electron transfer from the S-3p and Ga-4p states to S-3p and P-3p.

A New 1-D Chain ofγ-Hg_(3)S_(2)Br_(2)Constructed from Hg_(4)S_(4)Squares:Solid-state Synthesis,Structure and Optical Properties

A new metal chalcogenide,γ-Hg_(3)S_(2)Br_(2)(1),has been prepared by moderate-temperature solid-state reaction,and its crystal structure was determined by single-crystal X-ray diffraction analysis.Compound 1 crystallizes in space group Cmmm of orthorhombic system with a=9.1923(18),b=18.2262(5),c=4.6251(7)Å,V=774.9(3)Å^(3)and Z=4.In the structure,two Hg(1),two Hg(2)and four S(1)atoms form a near square Hg_(4)S_(4),and such squares are linked by Hg(3)atoms nearly linearly coordinated to two S1 atoms of two parallel Hg_(4)S_(4)squares to form one-dimensional infinite Hg_(6)S_(4)chains along c direction.Optical absorption spectra reveal the presence of sharp optical gap of 2.80 eV for 1.IR spectrum,TGA and electric resistivity have been investigated.

Synthesis,Photochromism and Switchable Photoluminescence of a Cd-based Metalloviologen Complex

A novel metalloviologen complex{[Cd(PhSQ)(HTBC)(H_(2)O)_(2)]·1.25 H_(2)O}n(1)based on N-(4-sulfophenyl)-4,4’-bipyridinium(PhSQ)and monoprotonated trimesic acid(HTBC)has been prepared and structurally characterized.Complex 1 has been characterized by elemental analysis,IR,thermogravimetric analyses,UV-Vis spectra and X-ray crystallography.The coordination geometry of Cd(Ⅱ)ion is a pentagonal bipyramid.Complex 1 displays a zigzag chain along the b axis,and such chains are extended into a 2 D layer supramolecular network through hydrogen bonding and π…π interactions.Moreover,complex 1 exhibits reversible photochromic and switchable luminescent behaviors via UV light irradiation at room temperature induced by the photogenerated radicals via a photo-induced electron transfer(PET)mechanism.