Zn-Ln(Ⅲ)(Ln=Eu, Tb)杂核配合物的合成、 结构及光物理性质

采用溶剂热方法合成了两种具有良好发光性能的d-f异核金属配合物EuZn(C8H7O3)5(phen)(H2O)(1)和TbZn(C8H7O3)5(phen)(H2O)(2). 采用单晶X射线衍射表征了晶体结构. 结果表明, 两种配合物是同构的, 在配合物中, Zn为五配位, Ln(Ⅲ)[Ln(Ⅲ)=Eu, Tb]为八配位. 金属间通过对甲氧基苯甲酸根的羧基(—COO)基团成桥联结. 测定了配合物的紫外-可见吸收光谱、 红外光谱和荧光光谱. 讨论了配位环境对荧光性质的影响以及配合物分子内能量传递问题.     

系列双核Ln(Ⅲ)配合物的晶体结构和磁性

合成了分子式为[Ln2(phen)2L],phen=C12H8N2[A Ln=Nd,L=(CH3COO)4(ONO2)2,B Ln=Sm,L=(C6H5COO)6,C Ln=Eu,L=(C6H5COO)6]3种同双核配合物.用X射线四圆衍射仪测定了3种化合物的结构.在化合物A分子中,2个Nd(Ⅲ)原子由4个CH3COO-基团桥联,以phen和ONO2-为端基,构成了一个具有C2对称性的双核分子.配合物B和C具有完全相同的结构,它们是以4个苯甲酸根为桥,2个phen和2个C6H5COO-为端基的中心对称双核分子,其中6个苯甲酸根的成键状态可分为3种状况.在3种化合物中,每个Ln均为9配位,呈不规则多面体.Ln-Ln距离,A为0.397nm,B和C均为0.405nm.测定了各配合物的变温磁化率,通过对磁性质研究,发现化合物A在低温下具有反铁磁物质行为.并由理论拟合,求得了磁参数g,J值.     

4-[(1,3-二氧代丁基)氨基]苯甲酸稀土配合物的合成、表征及发光性质

在乙醇体系中,由主配体4-[(1,3-二氧代丁基)氨基]苯甲酸(H2L,C11H11NO4)、稀土硝酸盐及辅助配体邻菲啰啉(phen)反应合成了两个系列8个配合物[Ln2(L)3(H2O)4]n(Ln=Sm(1),Eu(2),Tb(3),Dy(4));[Ln2(NO3)2(L)2(phen)2]n(Ln=Sm(5),Eu(6),Tb(7),Dy(8))。用元素分析、红外光谱、摩尔电导、热重分析进行表征,确定了产物的化学组成,推断了相应的结构。测定了室温时固体产物的激发和发射光谱,结果表明:由主辅配体共同配位的三元配合物的发光强度好于无辅助配体参与的二元配合物。测定了三元配合物的荧光寿命,其中铕和铽配合物显示较长的荧光寿命。     

两个3d-4f杂核配合物[Fe(phen)3]2[FeLn(H2O)(tiron)3]·6H2O的合成、晶体结构和磁性(Ln=HoⅢ,YbⅢ)

Ln2O3、硝酸铁、邻菲罗啉和钛铁试剂(tiron)通过水热法自组装合成了2个异质同晶的3d-4f杂核配合物[Fe(phen)3]2[FeLn(H2O)(tiron)3]·6H2O,其中,Ln=HoⅢ(1)和YbⅢ(2)。X-射线单晶衍射分析表明,晶体属立方晶系,P213空间群。3个tiron4-配体利用酚氧桥联Ln3+和Fe3+形成具有C3对称性的[FeLn(H2O)(tiron)3]6-异双核配位单元,其中七配位的Ln3+呈现一种畸变的单帽反三棱柱配位构型。配阳离子[Fe(phen)3]3+通过phen-phen之间的π-π相互作用和与配阴离子间的静电引力等作用组装成三维的超分子。在2～300 K温度范围内测试了配合物的变温磁化率,结果表明,Ln(Ⅲ)-Fe(Ⅲ)之间存在反铁磁性相互作用。     

两个含有2,6-二氟苯甲酸配体稀土配合物的合成及晶体结构

利用2,6-二氟苯甲酸和1,10-菲咯啉作为配体分别与Tm^3+、Yb^3+离子在常温下反应,制得2个稀土配合物[Tm(dfba)2(phen)(μ2-dfba)]2 (1)和[Yb(dfba)2(phen)(μ2-dfba)]2 (2)(dfba-=2,6-二氟苯甲酸根,phen=1,10-菲咯啉)。用元素分析、红外光谱对2个稀土配合物进行了表征,并用单晶X射线衍射确定了配合物的晶体结构;测定了配合物1和2的热稳定性。结构分析表明配合物1和2具有相似的晶体结构。每个Ln^3+与2个dfba-配体和1个phen分子配位,形成[Ln(dfba)2(phen)]+结构单元,[Ln(dfba)2(phen)]+单元再通过2个不同的dfba-配体桥联形成双核分子[Ln(dfba)2(phen)(μ2-dfba)]2(Ln=Tm,Yb)。     

系列Ln(Ⅲ)配位聚合物(Ln:Eu,Sm,Tb,Gd)的合成及其荧光分析

采用水热法合成了4个具有1D结构的Ln(Ⅲ)配位聚合物,[Eu2(C9H7O2)6(C9H7O2H)(C2H5OH)]n(1)、[Sm(C9H7O2)3]n(2)、[Tb(C9H7O2)3]n(3)和[Gd(C9H7O2)3]n(4)(C9H8O2=肉桂酸)。通过X射线单晶衍射确定了它们的结构。这4个Ln(Ⅲ)配合物中,Ln(Ⅲ)的配位数均为9,桥配体均为肉桂酸根,但其配位方式有差异。对配合物进行了IR、UV-Vis-NIR和荧光光谱等表征。分析了各配合物的荧光发射,结果表明,在可见区,配合物1发射较明显的红光,配合物2、3发射绿光,配合物4发射蓝光,但很弱。讨论了具有刚柔相混杂性质的肉桂酸配体对配位聚合物的构筑及稀土离子发光的影响。     

含氟二羧酸和含氮配体与过渡金属(Ⅱ)配合物的合成、表征及晶体结构

水热法合成了5个新的配位聚合物:[Cd(TFSA)(2,2’-bpy)2]n(1),[Mn(HFGA)(phen)2]n(2),[Co(TFSA)(bpp)2(H2O)2]n(3),[Zn(TFSA)(bpp)2(H2O)2]n(4)和[Cu(HFGA)(phen)]n(5)(TFSA=四氟丁二酸,HFGA=六氟戊二酸,2,2’-bpy=2,2’-联吡啶,phen=1,10-邻菲啰啉,bpp=1,3-二吡啶基丙烷),通过X射线单晶衍射确定了配合物的晶体结构.配合物1和2具有相似的1D链结构,四氟丁二酸和六氟戊二酸以两个单齿羧基氧原子分别配位于Cd2+和Mn2+离子,2,2’-联吡啶和1,10-邻菲啰啉分别螯合配位于Cd2+和Mn2+离子.配合物3和4具有相似的1D链结构,1,3-二吡啶基丙烷以两个端基氮原子桥联金属离子,四氟丁二酸和六氟戊二酸分别以单齿方式配位.配合物5是具有{4.82}拓扑的2D网结构,六氟丁二酸配体通过单齿/双齿-桥联模式连接Cu2+离子.5个配合物均通过分子间弱作用进一步构筑成3D超分子结构.     

2D氢键网络镉配合物Cd(pyridine-2-sulfonato)2(H2O)2和锌配合物Zn(pyridine-2-sulfonato)2(H2O)2的合成和晶体结构

合成了镉的吡啶-2-磺酸配合物Cd(C5H4NSO3)2(H2O)2 1和锌的吡啶-2-磺酸配合物Zn(C5H4NSO3)2(H2O)2 2。 研究表明, 2个化合物属异质同晶, 均属单斜晶系, 空间群为C2/c. 化合物1晶胞参数为:a = 13.7671(5), b = 7.2778(3), c = 16.1559(9) ? b = 106.656(3)? V = 1550.8(1) 3, Z = 4, Dc = 1.990 g/cm3, m =1.719 mm-1, F(000) = 920, R = 0.0225, wR = 0.0584, 共收集到1759个独立衍射点, 其中I≥2(I)的可观测点为1681个;化合物2晶胞参数为:a = 13.711(1), b = 7.1451(9), c = 15.972(1) , b =107.079(5)? V = 1495.7(3) 3, Z = 4, Dc = 1.855 g/cm3, m = 1.964 mm-1, F(000) = 848, R = 0.0310, wR = 0.0831, 共收集到1707个独立衍射点, 其中I≥2(I)的可观测点为1592个。在2个标题配合物中, Cd2+离子(或Zn2+离子)由2个吡啶-2-磺酸中的2个氮和2个氧以及2个水分子中的2个氧配位形成畸变的N2O4八面体配位构型。每个配合物分子具有晶体学2次旋转轴对称性。配合物分子之间通过许多OH(配位水分子)LO(未配位磺酸根)氢键联结成二维结构网络。     

含有二维有序水层的癸二酸锌(Ⅱ)、钴(Ⅱ)超分子配合物的构筑

室温下,在醇水溶液中合成了2个新型配合物,[Zn(phen)3]2·[Zn(C10H16O4)·(H2O)3]·(C10H16O4)2·20H2O(C10H18O4=癸二酸)(1)和[Co(phen)3]2·[Co(H2O)6]·(C10H16O4)3·30H2O(2),并对配合物进行了元素分析分析、红外光谱分析、热重分析以及晶体结构研究.配合物(1)的基本结构单元中含有一个电中性配位单元[Zn(C10H16O4)·(H2O)3]、二个配位阳离子[Zn(phen)3]2+、二个游离的癸二酸根和20个晶格水.Zn原子有两种配位模式,在[Zn(phen)3]2+配位单元中Zn原子与三个邻菲啰啉的六个N原子配位,构成略有畸变的八面体,Zn原子位于八面体的对称中心;在[Zn(C10H16O4)·(H2O)3]配位单元中Zn原子采取五配位的三角双锥构型,两个羧基均采取单齿配位,同一个癸二酸根与相邻的不同Zn原子配位,将相邻的[Zn(C10H16O4)·(H2O)3]配位单元连接起来,自组装得到了无限链状结构.配合物以癸二酸根为模板在ab平面形成了有序水层,该水层由5元,6元水簇,以及其他由羧基参与的各元环组成.与一般常见的6元水簇不同,配合物1中的6元水簇采取了高能量的类似苯环的平面构象.配合物(2)的基本结构单元中含有一个[Co(H2O)6]2+配位阳离子、二个[Co(phen)3]2+配位阳离子、三个游离的癸二酸根和30个晶格水.Co原子也有两种配位模式.在[Co(phen)3]2+配位单元中,Co原子与三个邻菲啰啉的六个N原子配位,构成略有畸变的八面体,Co原子位于八面体的对称中心.在[Co(H2O)6]2+配位单元中Co(II)与6个配位水的氧原子配位,6个配位水中的6个原子和Co(Ⅱ)形成八面体结构.通过水分子之间及水分子和羧基阴离子间的氢键形成了二维有序水层,二维水层中最小的构筑基元为6元环的水,最大的构筑基元为16元环水,每个水环中分别含有6个和16个游离的没有配位的水分子,水分子之间通过很强的氢键作用形成环形的超分子水簇.这些基元片断在二维空间扩展开来,形成二维有序水层.有趣的是,在该水层上通过水分子之间的分子间氢键形成了16元大环水簇,它与两端的六元环共用六条边,每一个16元水环中含有16个游离的没有配位的水分子,水分子之间通过氢键作用形成环形超分子水簇,每个水分子同时作为氢键的给体和受体.[Co(H2O)6]2+和四个羧酸根离子位于十六元环水的中心,与其周围的游离水分子形成了十二个氢键,同时与环外的游离水和羧酸根形成了十个氢键,对大环水聚集体起到稳定作用.     

以芳香族多羧酸为配体的Ni(II)配位超分子的研制及光诱导下的表面电子行为

采用水热方法合成了2个Ni(II)配合物[Ni3(btc)2(H2O)14]·4H2O(1)和[Ni2(btec)(bipy)2(H2O)6]·2H2O(2), (H3btc=1,3,5-benzenetricarboxylic acid, H4btec=1,2,4,5-benzenetetracarboxylic acid, bipy=2,2'-bipyridyl). 通过X射线单晶衍射(XRD)、红外光谱(IR)、紫外-可见-近红外吸收光谱(UV-Vis-NIR)对化合物进行了表征. 结果表明, 化合物(1)是由2个均苯三甲酸根桥连的三核Ni(II)离子的化合物, 而化合物(2)是由1个均苯四甲酸根桥连的双核化合物, 分子中bipy分子作为端基配体. 分子中大量的水分子和羧酸根的存在使2个化合物分别被连成具有三维(3D)和二维(2D)结构的配位超分子化合物. 着重研究了化合物的表面光电压光谱(SPS), 并将其与UV-Vis-NIR吸收光谱进行了分析和对比, 发现SPS 中表面光伏响应带与UV-Vis-NIR 吸收光谱的吸收峰在数量和位置上都是一一对应的. 此外, 对比2个化合物的表面光电压光谱可以看出,配合物的结构及中心金属的配位微环境对其表面光伏响应带的强度、位置和形状均有一定影响.     

Synthesis, crystal structure, and luminescent properties of 2-(2,2,2-trifluoroethyl)-1-indone lanthanide complexes

A new β-diketone, 2-(2,2,2-trifluoroethyl)-1-indone (TFI), which contains a trifluorinated alkyl group and a rigid indone group, has been designed and employed for the synthesis of two series of new TFI lanthanide complexes with a general formula [Ln(TFI)(3)L] [Ln = Eu, L = (H(2)O)(2) (1), bpy (2), and phen (3); Ln = Sm, L = (H(2)O)(2) (4), bpy (5), and phen (6); bpy = 2,2'-bipyridine, phen = 1,10-phenanthroline]. X-ray crystallographic analysis reveals that complexes 1-6 are mononuclear, with the central Ln(3+) ion eight-coordinated by six oxygen atoms furnished by three TFI ligands and two O/N atoms from ancillary ligand(s). The room-temperature photoluminescence (PL) spectra of complexes 1-6 show strong characteristic emissions of the corresponding Eu(3+) and Sm(3+) ions, and the substitution of the solvent molecules by bidentate nitrogen ligands essentially enhances the luminescence quantum yields and lifetimes of the complexes.     

Luminescence of LnIII dithiocarbamate complexes (Ln = La, Pr, Sm, Eu, Gd, Tb, Dy)

We have discovered room temperature photoluminescence in Sm3+ and Pr3+ dithiocarbamate complexes. Surprisingly, these complexes exhibit more intense emission than those of the Eu3+, Tb3+, and Dy3+ analogues. The electronic absorption, excitation, and emission spectra are reported for the complexes [Ln(S2CNR2)3L] and NH2Et2[Ln(S2CNEt2)4], where Ln = Sm, Pr; R = ethyl, ibutyl, benzyl; and L = 1,10-phenanthroline, 2,2'-bipyridine, and 5-chloro-1,10-phenanthroline. The lowest ligand-localized triplet energy level (T1) of the complexes are determined from the phosphorescence spectra of analogous La3+ and Gd3+ chelates. The luminescence decay curves were measured to determine the excited-state lifetimes for the Pr3+ and Sm3+ complexes. X-ray crystal structures of Sm(S2CNiBu2)3phen, Pr(S2CNEt2)3phen, and Pr(S2CNiBu2)3phen are also reported.     

Crystal structures and thermal decomposition mechanism of four lanthanide complexes with halogen-benzoic acid and 1,10-phenanthroline

This paper describes syntheses and structure determination of four lanthanide complexes [Nd(2-Cl-4-FBA) 3 phen] 2 (1, 2-Cl-4-FBA = 2-chloro-4-fluorobenzoate, phen = 1,10-phenanthroline), [Ln(2,5-DClBA) 3 phen] 2 (Ln = Sm(2) and Tb(3), 2,5-DClBA = 2,5-dichlorobenzoate) and [Sm(2-Cl-4,5-DFBA) 3 (phen)(H 2 O)] 2 (4, (2-Cl-4,5-DFBA = 2-chloro-4,5-difluorobenzo- ate). The complexes were characterized by elemental analysis, infrared and ultraviolet spectra, and X-ray single-crystal diffraction. In the molecular structures of 1 4, two Ln 3+ ions are linked by four carboxyl groups, with two of them in a bridging bidentate mode and the other two in a bridging-chelating tridentate mode, forming four binuclear molecules. In addition, each Ln 3+ ion is also chelated to one phen molecule and one carboxyl group in the complexes, except each Sm 3+ ion in 4 which is bonded to one carboxyl group by unidentate mode and one H 2 O molecule. There are two different coordination polyhedrons for each Nd 3+ ion in the two similar molecular structures of 1 and they are a distorted monocapped square antiprismatic and a distorted tricapped triangular prism conformation, respectively. The coordination polyhedron for each Ln 3+ ion in 2 4 is a nine-coordinated distorted mono-capped square antiprismatic conformation. The complex 3 exhibits green luminescence under the radiation of UV light. The thermal decomposition behaviors of the complexes have been discussed by simultaneous TG/DSC-FTIR technique. The 3D surface graphs for the FTIR spectra of the evolved gases were recorded and the gaseous products were identified by the typical IR spectra obtained at different temperatures from the 3D surface graphs. Meanwhile, we discussed the nonisothermal kinetics of 1 4 by the integral isoconversional non-linear (NL-INT) method.     

基于对羟基苯乙酸及邻菲咯啉的稀土配合物的合成、晶体结构和荧光光谱

在乙醇-水体系中合成了5个对羟基苯乙酸及邻菲咯啉稀土配合物:其中4个配合物[RE(HPAA)3(phen)2].2H2O(RE=Eu(1),Tb(2),Dy(3),Yb(4))具有相同的结构和类似的化学组成;第5个配合物是[Yb(HPAA)2(H2O)2(phen)2](HPAA).(HHPAA).2H2O(5),HHPAA=对羟基苯乙酸,C8H8O3;phen=1,10-邻菲咯啉),其结构和化学组成与前4个配合物不同。并通过元素分析、红外光谱、热重分析和粉末X-射线衍射对产物进行表征,用单晶X-射线衍射方法测定了配合物5的晶体结构。配合物5(C56H53N4O16Yb)属于三斜晶系,空间群P21/c,晶胞参数:a=2.206 52(3)nm,b=1.368 76(2)nm,c=1.754 14(2)nm,β=101.167(1)°,晶胞体积:V=5.19754(12)nm3,晶胞内结构基元数Z=4,分子量Mr=1211.06。测定了铕、铽和镝配合物的荧光光谱,结果表明,在形成配合物后,依然显示铕髥离子、铽髥离子和镝髥离子的特征发射,这表明配体将吸收的能量有效地转移给了中心离子,配体起到了很好的敏化作用。     

Isolations and characterization of highly water-soluble dimeric lanthanide citrate and malate with ethylenediaminetetraacetate

Highly water-soluble lanthanum and cerium citrates or malates with ethylenediaminetetraacetate (NH(4))(8)[Ln(2)(Hcit)(2)(EDTA)(2)]·9H(2)O [Ln = La, 1; Ce, 2], K(8)[La(2)(Hcit)(2)(EDTA)(2)]·16H(2)O (3) and K(6)[Ln(2)(Hmal)(2)(EDTA)(2)]·14H(2)O [Ln = La, 4; Ce, 5] (H(4)cit = citric acid, H(3)mal = malic acid, and H(4)EDTA = ethylenediaminetetracetic acid) were prepared from the reactions of lanthanide ethylenediaminetetraacetate trihydrates with citric or malic acid at pH 5.0-6.5. These compounds were characterized by elemental analyses, IR, TG-DTG, solution (13)C{(1)H} NMR, solid state (13)C NMR spectra and X-ray structural analyses. The main structural feature of the compounds consists of a dinuclear unit deca-coordinated by EDTA and citrate or malate. The α-hydroxy and α-carboxy groups of citrate and malate chelate in five-membered ring with one lanthanide ion, while one of the β-carboxy group coordinates with the other lanthanide ion, forming a dimeric structure. The other pendent β-carboxy groups in 1-3 form very strong intramolecular hydrogen bond with α-hydroxy groups [O1O7 2.594(4), 2.587(8) and 2.57(1) ? for 1-3 respectively]. (13)C NMR spectra of the lanthanum compounds show obvious downfield shifts based on solid and solution NMR measurements, indicating the coordinations of mixed-ligand in lanthanum complexes, while highfield shifts are observed in cerium complexes.     

Synthesis, crystal structure, and luminescent properties of novel Eu3+ heterocyclic beta-diketonate complexes with bidentate nitrogen donors

New tris(heterocyclic beta-diketonato)europium(III) complexes of the general formula Eu(PBI)3.L [where HPBI = 3-phenyl-4-benzoyl-5-isoxazolone and L = H2O, 2,2'-bipyridine (bpy), 4,4'-dimethoxy-2,2'-bipyridine (dmbpy), 1,10-phenanthroline (phen), or 4,7-diphenyl-1,10-phenanthroline (bath)] were synthesized and characterized by elemental analysis, Fourier transform infrared spectroscopy (FT-IR), 1H NMR, high-resolution mass spectrometry, thermogravimetric analysis, and photoluminescence (PL) spectroscopy. Single-crystal X-ray structures have been determined for the complexes Eu(PBI)3.H2O.EtOH and Eu(PBI)3.phen. The complex Eu(PBI)3.H2O.EtOH is mononuclear, and the central Eu3+ ion is coordinated by eight oxygen atoms to form a bicapped trigonal prism coordination polyhedron. Six oxygens are from the three bidentate HPBI ligands, one is from a water molecule, and another is from an ethanol molecule. On the other hand, the crystal structure of Eu(PBI)3.phen reveals a distorted square antiprismatic geometry around the europium atom. The room-temperature PL spectra of the europium(III) complexes are composed of the typical Eu3+ red emission, assigned to transitions between the first excited state (5D0) and the multiplet (7F0-4). The results demonstrate that the substitution of solvent molecules by bidentate nitrogen ligands in Eu(PBI)3.H2O.EtOH richly enhances the quantum yield and lifetime values. To elucidate the energy transfer process of the europium complexes, the energy levels of the relevant electronic states have been estimated. Judd-Ofelt intensity parameters (Omega2 and Omega4) were determined from the emission spectra for Eu3+ ion based on the 5D0 --> 7F2 and 5D0 --> 7F4 electronic transitions, respectively, and the 5D0 --> 7F1 magnetic dipole allowed transition was taken as the reference. The high values obtained for the 4f-4f intensity parameter Omega2 for europium complexes suggest that the dynamic coupling mechanism is quite operative in these compounds.     

The Complexes of Rare Earth Elements with 2,5-Dihydroxybenzoic Acid Preparation, properties and thermal decomposition

The conditions of the formation of rare earth(III) 2,5-dihydroxybenzoates have been studied; their compositions and solubilities in water at 293 K have been determined. The IR spectra of the anhydrous complexes with the general formula Ln(C7H5O4)3 have been recorded and their thermal decompositions in static air determined. During heating the anhydrous complexes of Y, Pr-Lu decompose to the oxides Ln2O3, Pr6O11 and Tb4O7 with formation of the intermediate Ln2(C7H4O4)3. The lanthanum complex decomposes to the oxide in three steps forming La2(C7H4O4)3 and La2O2CO3 as intermediates and the Ce(III) complex decomposes directly to CeO2. The properties of rare earth 2,5- and 2,4-dihydroxybenzoates have been compared. This revised version was published online in July 2006 with corrections to the Cover Date.