［Eu2(o-ClC6H4OCH2COO)6(C12H8N2)2(H2O)2］·(CH3)2SO的晶体结构和荧光光谱

标题配合物M=1892.01,单斜晶系,空间群P2₁/c, a=1.2975(3) nm, b=2.6591(9) nm, c=1.2118(3) nm, β=96.95(1)°, Z=2, D_c=1.577 g/cm³, T=293(2)K。最终的偏离因子R=0.0583。该配合物以二聚体形式存在,通过其中的桥联羧基形成了双核分子。该分子中羧基具有桥联双齿、桥联三齿和单齿三种配位模式,Eu-Eu之间的距离为0.4019(1) nm。在77K下测得配合物中Eu(Ⅲ)离子仅有一种格位。 ⁵D₀→ ⁷F_J(J=0～2)跃迁光谱说明Eu(Ⅲ)离子格位具有C₂对称性。     

一种双肟四核铜(Ⅱ)配合物的合成、结构及热稳定性研究

由螯合双肟配体3,3′-二甲氧基-2,2′-[(1,3-亚丙基)二氧双(氮次甲基)]二酚(H₂L)与四水合苦味酸铜作用,合成了一种新的四核铜(Ⅱ)配合物 [Cu₄L₂(pic)₄(H₂O)₂]·2CH₃COCH₃·2H₂O(pic^-=苦味酸根)。用X-射线单晶衍射仪测定了该配合物的晶体结构：配合物属单斜晶系,P2₁/c空间群,由4个Cu^Ⅱ离子,2个四齿的L2-单元,4个配位的苦味酸根(pic^-),2个配位的水分子,2个结晶的丙酮分子和2个结晶的水分子组成。Cu^Ⅱ离子的配位数为6,都具有稍微扭曲的八面体结构。且配合物分子通过分子间O-H…O氢键作用形成了1个二维超分子结构。     

两种溴代苯甲酸-铽配合物的合成、晶体结构与性质表征

溶液法合成了2种配合物[Tb(2-BrBA)₂(CH₃COO)(2，2′-bipy)]₂ (1)和[Tb(3-BrBA)₃(2，2′-bipy)]₂·2(3-HBrBA)·2H₂O (2)(2-BrBA=2-bromobenzoate，3-BrBA=3-bromobenzoate，2，2′-bipy=2，2′-bipyridine)，并用X-射线单晶衍射方法测定了其晶体结构。配合物1和2均属于三斜晶系和P1空间群。四元混配配合物1是具有反演中心的二聚体，其中Tb³⁺离子同时与2种不同的羧酸配体配位。4个2-BrBA以双齿桥联的方式把2个Tb³⁺离子联结起来，而乙酸根和2，2′-bipy分子则分别以双齿螯合的方式与Tb³⁺离子配位。配合物2是三元混配配合物，2个Tb³⁺离子通过4个双齿桥联的3-BrBA联结而成具有反演中心的二聚体，每个Tb³⁺离子还同时与1个双齿螯合的3-BrBA和1个2，2′-bipy分子配位。配合物1和2在紫外灯照射下能发出强烈的绿光，而且在它们的荧光光谱中都存在4条谱线：489、545、585和621 nm，分别对应于Tb³⁺离子的 ⁵D₄ → ⁷F₆、 ⁵D₄ → ⁷F₅、 ⁵D₄→ ⁷F₄和 ⁵D₄→ ⁷F₃跃迁。     

［Eu2(BA)6(bipy)2］的晶体结构和荧光光谱

标题配合物晶体属单斜晶系，P2₁/n空间群，晶胞参数a=1.4162(3) nm，b=1.5377(5) (nm), c=2.6017(5) nm, β=103.56(3°)， Z=4。标题配合物是双核分子，4个苯甲酸的羧基桥联两个中心Eu(Ⅲ)离子。它们又分别与1个苯甲酸的羧基的两个氧原子和一个联吡啶分子的两个氮原子螯合配位，形成4，4′-双帽三角棱柱体。两个Eu(Ⅲ)离子的Eu-O和Eu-N平均键长不等。两个Eu(Ⅲ)离子的化学环境略有不同。在配合物的 ⁷F₀→ ⁵D₀激发光谱里，580.17和580.31 nm处呈现两个锐峰，可以认为配合物具有两种Eu(Ⅲ)格位，选择激发配合物的 ⁵D₀能级，得到的 ⁵D₀→ ⁷F_1,2发光光谱表明配合物中Eu(Ⅲ)离子有不同的化学环境，这与晶体结构分析结果一致。     

三苯基锡9-蒽甲酸酯的合成、表征、荧光、热稳定性及量子化学研究

在甲醇中三苯基氢氧化锡与9-蒽甲酸反应,合成了有机锡配合物[PH₃Sn(O₂CC₁₄H₉)(MeOH)]₂·MeOH,经IR、¹H和¹³C-NMR、元素分析及X-射线单晶衍射表征结构。晶体结构分析表明：配合物中心锡原子为五配位畸变三角双锥构型。晶体中,配合物分子的羰基氧与近邻的甲醇氧、两相邻的甲醇氧间分别形成O-H…O氢键,组成一维S形链;经链内蒽环H与另一蒽环的C-H…π作用,进一步连接成梯状结构。两相邻梯状链间,通过配位甲醇的甲基H与另链苯环发生C-H…π作用扩展成二维网状。室温下,配合物在460 nm处有较强的荧光发射(λ_ex=360 nm)。热重分析表明,配合物在240 ℃以下能稳定存在。利用量子化学G03W软件,在LANL2DZ基组对配合物的稳定性、前沿分子轨道组成及能量进行研究。     

具有(6，3)拓扑构造的镝配合物的水热合成、晶体结构和荧光光谱

用水热合成的方法得到了配合物{[Dy(1,2-pda)_3/2(H₂O)]·H₂O}_n(1,2-pda=1,2-邻苯二乙酸根),用X-射线衍射单晶结构分析确定了该配合物的晶体结构。该晶体属于单斜晶系,C2/c空间群。配合物中每个Dy³⁺离子被6个1,2-邻苯二乙酸根环绕,相邻的6个Dy³⁺离子被6对1,2-邻苯二乙酸根连接,形成具有六角形的[Dy(1,2-pda)₆]₂团簇,这些团簇进一步被1,2-邻苯二乙酸根桥联而得到具有(6,3)拓扑构造的3D网络结构。所有的1,2-邻苯二乙酸根配体用桥联/螯合-桥联五齿和螯合-桥联/螯合-桥联六齿两种配位模式与Dy³⁺离子配位。每个Dy³⁺还键合1个水分子。九配位的Dy³⁺离子的配位环境可描述为扭曲的单帽四方反棱柱。在配合物的荧光光谱的481和574 nm处出现了2条谱线,分别对应于Dy³⁺离子的 ⁴F_5/2 → ⁶H_15/2和 ⁴F_5/2 → ⁶H_13/2的跃迁。     

含咔唑基团联吡啶衍生物为中性配体的铕配合物的合成和发光性质研究

以2,2′-联吡啶(L1)为基础,合成了5,5′-二溴-2,2′-联吡啶(L2),5-咔唑-5′-溴-2,2′-联吡啶(L3),5,5′-二咔唑-2,2′-联吡啶(L4)3个N,N-双齿配体,然后以二苯甲酰甲烷(DBM)作为第一配体合成了这4种配体相应的铕配合物。在387 nm激发条件下,配合物都表现出非常强的铕离子⁵D₀-⁷F_J (J=0,1,2,3,4)的特征发射。引入咔唑基团后,不仅扩大了配合物吸收光能的范围、增强了配合物的吸收强度,而且提高了配合物的光致发光性能。     

一维链状3-碘苯甲酸铽配合物的合成、晶体结构和性质表征

溶液法合成了配合物{[Tb(3-IBA)₃(H₂O)₂]·0.5(4,4′-bipy)}_n(3-IBA=3-碘苯甲酸根;4,4′-bipy=4,4′-联吡啶),并通过X-射线衍射单晶结构分析、红外光谱、紫外光谱、荧光光谱以及热重分析对配合物进行了结构和性质表征。配合物晶体属三斜晶系,P1空间群。该配合物具有一维链状结构。Tb³⁺离子与8个O原子配位,其中6个O原子来自5个3-碘苯甲酸根,2个O原子来自水分子。相邻Tb³⁺离子通过2个双齿桥联的3-碘苯甲酸根联结成一维链状结构。未配位的4,4′-联吡啶分子与配位水分子之间形成氢键,并将相邻的一维链联结起来形成二维网状结构。沿a轴的分子堆积形成一维孔道,是由于相邻一维链的苯环之间部分重叠而形成的。在紫外光照射下,配合物发出很强的绿色荧光。配合物的荧光光谱中,4个峰位于490、544、583和619 nm,分别对应于Tb³⁺离子的⁵D₄→⁷F₆、⁵D₄→⁷F₅、⁵D₄→⁷F₄和⁵D₄→⁷F₃跃迁。     

双核铜配合物的合成与晶体结构

室温下,在吡啶-2-甲酸存在下,过氧化苯甲酰和金属铜粉经过氧化加成反应生成双核铜(Ⅱ)配合物,［Cu(C₆H₅NO₂)(C₆H₅COO)₂］₂,X-射线单晶结构分析确定了配合物的分子和晶体结构,晶体属单斜晶系,空间群为P2₁/n,晶胞参数如下：a=10.423(5)?, b=10.511(3)?, c=16.896(11)?, β=99.37(5)°,V=1826.4?^{3。中心铜离子由桥式双齿苯甲酸根和吡啶-2-甲酸配位形成二聚双核配合物,同时通过红外光谱和热分析表征了配合物的性质。}     

基于双齿咪唑席夫碱配体的两个手性自旋转换铁(Ⅱ)配合物

以含有苯环和咪唑环的手性双齿席夫碱为配体, 合成了2个纯手性单核自旋转换铁(Ⅱ)配合物fac-Δ -[Fe(S-L₁)₃][ClO₄]₂ (1), mer-Λ -[Fe(R-L₂)₃][ClO₄]2· Et₂O (2)(L₁=1-对氯苯基-N-(1-正丙烯基-¹H-咪唑-2-亚甲基)乙胺; L₂=1-苯基-N-(1-异丙烯基-1H-咪唑-2-亚甲基)乙胺)。利用X-射线单晶衍射、元素分析(EA)、红外光谱(IR)、核磁共振氢谱(¹H NMR)、紫外光谱(UV)、圆二光谱(CD)等手段对配合物结构进行了表征。X-射线单晶衍射表明在配合物1和2中, 铁(Ⅱ)金属中心与3个不对称双齿手性席夫碱配体中的6个氮原子配位形成八面体配位环境。配合物1中每个结构基元中包含1个[Fe(L_n)₃]²⁺阳离子和2个高氯酸根阴离子。而配合物2中每个结构基元中包含2个[Fe(L_n)₃]²⁺阳离子、4个高氯酸根阴离子和1个乙醚分子。由于铁(Ⅱ)中心周围手性配体的螺旋协调配位使[Fe(L_n)₃]²⁺形成单一构型。Fe(Ⅱ)-N键长表明配合物1中的铁(Ⅱ)在低自旋状态, 而配合物2中的铁(Ⅱ)在高自旋状态。在[Fe(L_n)₃]²⁺中, 相邻配体中的苯环和咪唑环形成分子内π-π相互作用。配合物1和2通过分子间C-H…π和C-Cl…π相互作用形成超分子结构。CD光谱证实配合物1和2在溶液中的光学活性。磁性测试表明配合物1和2分别在372 K和146 K发生自旋转换。由于配合物1和2具有不同的堆积方式和分子间相互作用, 导致1和2表现出不同的自旋转换温度。     

Synthetic and structural studies of some trivalent lanthanide metal complexes of o -hydroxyacetophenone (N-benzoyl)glycyl hydrazone

o-Hydroxyacetophenone (N-benzoyl)glycyl hydrazone (o-HABzGH) forms complexes of the types [M(o-HABzGH)Cl₂(H₂O)₂]Cl and [M(o-HABzGH-2H)OH(H₂O)₂], where M = Y(III), Gd(III), Tb(III) and Dy(III). The complexes have been characterized by elemental analyses, molar conductance, magnetic susceptibility, infrared, electronic,¹H NMR and¹³C NMR spectral techniques. The nephelauxetic ratio (β), covalency (δ), bonding parameter (b ^1/2) and angular overlap parameter (η) have been calculated from Dy(III) complexes. Infrared and NMR spectral studies show thato-HABzGH acts as a neutral bidentate ligand in the adduct complexes and as a dinegative tridentate one in the neutral complexes. A coordination number of six has been proposed for the metal ion in all the complexes.     

Syntheses,crystal structures,and spectral properties of Mn(II) and Co(II) complexes with 3-(p-chlorophenyl)- 4-(p-methylphenyl)-5-(2-pyridyl)-1,2,4-triazole

Two new complexes, trans-[MnL₂(NCS)₂] (1) and trans-[CoL₂(H₂O)(EtOH)](ClO₄)₂?·?H₂O (2) with asymmetrical triaryltriazole ligands [L?=?3-(p-chlorophenyl)-4-(p-methylphenyl)-5-(2-pyridyl)-1,2,4-triazole], have been synthesized and characterized by elemental analysis, FT-IR, ESI-MS, and single-crystal X-ray diffraction. In the complexes each L adopts a chelating bidentate mode via the nitrogen of pyridyl and triazole. Both complexes have a similar distorted octahedral core with two NCS^? ions in the trans position in 1, while one H₂O and one EtOH are present in the axial sites in 2.     

Dinuclear peroxo complexes of molybdenum(VI) containing Mannich base ligands

Dinuclear molybdenum(VI) peroxo complexes containing Mannich base ligands having formulae [Mo₂O₄(O₂)₂L-L(H₂O)₂] · H₂O [where L-L = N-[1-morpholinobenzyl] acetamide (MBA), N-[1-piperidinobenzyl] acetamide (PBA), N-[1-morpholino(-4-nitrobenzyl)] benzamide (MPNBB), N-[1-piperidino(-3-nitrobenzyl)] benzamide (PMNBB), N-[1-morpholino(-2-nitrobenzyl)] acetamide (MONBA), and N-[1-morpholino(-3-nitrobenzyl)] acetamide (MMNBA)] have been synthesized by stirring ammonium heptamolybdate with excess 30% aqueous hydrogen peroxide followed by treatment with ethanolic solution of corresponding ligands. The complexes have been characterized by elemental analysis, molar conductance, magnetic measurements, infrared (IR), electronic, TGA/DTA, mass spectral, and ¹H NMR studies. The complexes are non-electrolytes and diamagnetic. The IR spectral studies suggest that the ligands are bidentate to metal through carbonyl oxygen and ring nitrogen. Thermal analyses provide conclusive evidence for the presence of coordinated, as well as lattice water in the complexes. Dinuclear complexes preserve the individuality of the molybdenum oxo peroxo core. The complexes exhibit higher antibacterial activity against bacterium Ralastonia solanacearum (Pseudomonas solanacearum) than the free ligands.     

Stereochemical,biochemical and ligation behaviour of divalent platinum complexes of sulfur and nitrogen donor agents

Divalent Pt complexes of o-FC₆ H₄ C(H)NNC(SH)SCH₂ Ph(L¹H) and o-FC₆ H₄ C(Me)NNC(SH)SCH₂ Ph(L ²H) have been synthesized and characterized thoroughly by analytical data, conductance measurements, molecular weight determinations, magnetic measurements, i.r., electronic, ¹H-n.m.r. and ¹⁹F-n.m.r. spectral studies. The spectral data are consistent with a square planar geometry around Pt^IIin which the ligand acts as a neutral bidentate and monobasic bidentate ligand coordinating through nitrogen and sulfur atoms. Ligands and their metal complexes were tested against certain microorganisms to assess their antimicrobial properties and the results are indeed positive.     

Hydrothermal syntheses and crystal structures of two Zn(II) complexes with 1-substituted-1H-[1,2,3]-triazole-4-carboxylic acid

Two new Zn(II) complexes, [Zn(L)₂(H₂O)₂] where L is 1-substituted 5-methyl-1H-[1,2,3]-triazole-4-carboxylic acid, have been synthesized and characterized by elemental analysis, FT–IR, and solid-state fluorescent emission spectroscopy. Structures have been established by single-crystal X-ray diffraction, revealing the discrete nature of the complexes in which Zn centers adopt slightly distorted octahedral geometry. In the complexes, the 1-substituted 5-methyl-1H-[1,2,3]-triazole-4-carboxylic acid is bidentate.     

Syntheses, structures and properties of two new neodymium complexes with N-P-acetamidobenzenesulfonyl-glycine acid

Two new neodymium complexes, [Nd₂(abglyH)₆(2,2′-bipy)₂(H₂O)₂] · 4H₂O 1 and {[Nd(abglyH)₃(H₂O)₂] · (4,4′-bipy) · 7H₂O}_n 2 (abglyH₂ = N-P-acetamidobenzenesulfonyl-glycine acid, 2,2′-bipy = 2,2′-bipyridine, 4,4′-bipy = 4,4′-bipyridine), have been synthesized and their structures have been measured by X-ray crystallography. In 1, nine-coordinated Nd(III) ions are bridged by two syn–syn bidentate and two tridentate bridging carboxylate groups from four different abglyH⁻ anions to form dinuclear motifs, which are further connected into a 3-D supramolecular framework via hydrogen bonds between the binuclear motifs and the uncoordinated water molecules. In 2, eight-coordinated Nd(III) ions are linked by six carboxylate groups adopting a syn–syn bidentate bridging fashion to form a 1-D inorganic–organic alternating linear chain. These polymeric chains generate microchannels extending along the a direction, and these cavities are occupied by discrete tetradecameric water clusters, which interact with their surroundings and finally furnish the 3-D supramolecular network via hydrogen bonds. At the same time, π–π stacking interactions between benzene rings from abglyH⁻ anions also play an important role in stabilizing the network.     

Novel bifunctional lanthanide‐centered nanophosphors for latent fingerprint detection and anti‐counterfeiting applications

Production of hybrid organic/inorganic complexes such as lanthanide phosphors in the nanodomain for human fingerprint visualization and anti‐counterfeiting ink under biocompatible UVA and blue light has not yet been studied that thoroughly. This paper presents the preparation of novel, bifunctional, green and red nanophosphors based on Eu³⁺ and Tb³⁺ complexes with quinolinone ligand (H₂L). They have been prepared and characterized for latent fingerprint detection and anti‐counterfeiting ink applications. The analytical data confirm that the ligand acts in a monoanionic bidentate manner through OO donor sites, forming mononuclear complexes, formulated as [Ln(HL)₃(C₂H₅OH)₃] (Ln = Eu³⁺ or Tb³⁺; L = 1‐ethyl‐4‐hydroxy‐3‐(nitroacetyl)quinolin‐2‐(1H)‐one). The Eu³⁺ and Tb³⁺ complexes have nanospherical morphologies with average particle sizes of 17 and 5 nm, respectively. Pure red and green photoluminescence with long lifetime values has been obtained from the Eu³⁺ and Tb³⁺ complexes, respectively, under non‐harmful UVA and blue illumination. Latent fingerprint details, including their characteristic three levels, have been clearly identified from various forensic (non‐porous, semi‐porous, highly fluorescent porous) substrates using red (Eu³⁺) and green (Tb³⁺) nanophosphors. The green nanophosphor powder has a greater capability for visualizing latent fingerprints from highly fluorescent porous surfaces as compared to the red one. Both nanophosphor complexes have been used to develop luminescent ink for anti‐counterfeiting applications.     

Structural,spectroscopic, and biological aspects of S∩N donor Schiff-base ligands and their chromium(III) complexes

New chromium(III) complexes are synthesized by classical thermal and microwave (MW)-irradiated techniques. The Schiff bases 2-acetylfuran-S-benzyldithiocarbazate (L¹H), 2-acetylthiophene-S-benzyldithiocarbazate (L²H), 2-acetylpyridine-S-benzyldithiocarbazate (L³H), and 2-acetylnaphthalene-S-benzyldithiocarbazate (L⁴H) were prepared by condensation of -S-benzyldithiocarbazate in ethanol with the respective ketones by using MW as well as conventional methods. The chromium(III) complexes have been prepared by mixing CrCl₃ · 6H₂O in 1 : 1 and 1 : 2 molar ratios with monofunctional bidentate ketimines. The structure of the ligands and their transition metal complexes were confirmed by elemental analysis, melting point determinations, molecular weight determinations, infrared (IR), electronic and electron paramagnetic resonance (EPR) spectral, and X-ray powder diffraction studies. On the basis of these studies it is clear that the ligands coordinated to the metal atom in a monobasic bidentate mode by S∩N donors. Thus, an octahedral environment around the chromium(III) has been proposed. The growth inhibiting potential of the ligands and complexes has been assessed against a variety of fungal and bacterial strains.     

Thermal and spectral studies of palladium(II) complexes

Palladium(II) complexes of type [Pd(L)Cl₂] [where L=2-aminopyridine-N-thiohydrazide (L¹), (2-aminopyridine-N-thio)-1,3-propanediamine (L²), benzaldehyde 2-aminopyridine-N-thiohydrazone (L³) and salicylaldehyde-2-aminopyridine-N-thiohydrazone (L⁴)] have been synthesized. The thiohydrazide, thiodiamine and thiohydrazones can exist as thione-thiol tautomer and coordinate as a bidentate N-S ligand. The ligands found to act in bidentate fashion. The complexes have been characterized by elemental analysis, IR, mass, electronic, ¹H NMR spectroscopic studies, and TG/DTA study. Antifungal studies of some complexes were also carried out. Various kinetic and thermodynamic parameters like order of reaction (n), activation energy (E _a), apparent activation entropy (S ^# ) and heat of reaction (ΔH) have also been carried out for one complex.     

Structural and spectroscopic characterization of two new blue luminescent pyridylbenzimidazole zinc(II) complexes

Luminescent metal complexes are used in photooptical devices. Zinc(II) complexes are of interest because of the ability to tune their color, their high thermal stability and their favorable carrier transport character. In particular, some zinc(II) complexes with aryl diimine and/or heterocyclic ligands have been shown to emit brightly in the blue region of the spectrum. Zinc(II) complexes bearing derivatized imidazoles have been explored for possible optoelectronic applications. The structures of two zinc(II) complexes of 5,6‐dimethyl‐2‐(pyridin‐2‐yl)‐1‐[(pyridin‐2‐yl)methyl]‐1H‐benzimidazole (L), namely dichlorido(dimethylformamide‐κO){5,6‐dimethyl‐2‐(pyridin‐2‐yl‐κN)‐1‐[(pyridin‐2‐yl)methyl]‐1H‐benzimidazole‐κN³}zinc(II) dimethylformamide monosolvate, [ZnCl₂(C₂₀H₁₈N₄)(C₃H₇NO)]·C₃H₇NO, (I), and bis(acetato‐κ²O,O′){5,6‐dimethyl‐2‐(pyridin‐2‐yl‐κN)‐1‐[(pyridin‐2‐yl)methyl]‐1H‐benzimidazole‐κN³}zinc(II) ethanol monosolvate, [Zn(C₂H₃O₂)₂(C₂₀H₁₈N₄)]·C₂H₅OH, (II), are reported. Complex (I) crystallized as a dimethylformamide solvate and exhibits a distorted trigonal bipyramidal coordination geometry. The coordination sphere consists of a bidentate L ligand spanning axial to equatorial sites, two chloride ligands in equatorial sites, and an O‐bound dimethylformamide ligand in the remaining axial site. The other complex, (II), crystallized as an ethanol solvate. The Zn^II atom has a distorted trigonal prismatic coordination geometry, with two bidentate acetate ligands occupying two edges and a bidentate L ligand occupying the third edge of the prism. Complexes (I) and (II) emit in the blue region of the spectrum. The results of density functional theory (DFT) calculations suggest that the luminescence of L results from π*←π transitions and that the luminescence of the complexes results from interligand charge‐transfer transitions. The orientation of the 2‐(pyridin‐2‐yl) substituent with respect to the benzimidazole system was found to have an impact on the calculated HOMO–LUMO gap (HOMO is highest occupied molecular orbital and LUMO is lowest unoccupied molecular orbital).