稀土吲哚-3-乙酸和吲哚-3-丁酸配合物的合成、表征及成键特性研究

在乙醇水溶液体系中合成了8种新的稀土吲哚-3-乙酸和吲哚-3-丁酸配合物,其通式为Ln(lA)₃·2H₂O和Ln(IB)₃·2H₂O(Ln=La,Nd,Sm,Er;IA=C₁₀H₈NO₂;IB=C₁₂H₁₂NO₂)。用元素分析、电导测定、电子吸收光谱、红外光谱、X光电子能谱和热重-差热分析确定了配合物的组成和成键特性。     

稀土冠醚类配合物的研究(Ⅺ)——硝酸钪、钇与二苯并-24-冠-8的固态配合物的合成及性质

以无水乙腈为反应介质,合成了硝酸钪及硝酸钇与DB24C8的固态配合物,确定其组成为Sc(NO₃)₃·DB24C8·2H₂O和[Y(NO₃)₃]₄·(DB24C8)₃·8H₂O,并对冠醚及其配合物的某些性质进行了对比研究。     

稀土-二苯甲酰甲烷、邻菲咯啉固态配合物及其掺杂硅胶共发光效应的光声光谱研究

合成了Eu(Dbm)₃·Phen同核和Eu_0.8Ln_0.2(Dbm)₃·Phen(Ln:Er³⁺,Y³⁺)异核固体配合物微晶粉末及其掺杂的SiO2凝胶样品,在300～800nm范围内测定了其光声光谱.结果表明,配合物Eu_0.8Er_0.2(Dbm)₃·Phen,Eu(Dbm)₃·Phen和Eu_0.8Y_0.2(Dbm)₃·Phen配体吸收处的光声强度依次减弱;而Eu_0.8Y_0.2(Dbm)₃·Phen和Eu(Dbm)₃·Phen配合物掺杂的凝胶则情况相反.研究发现,光声强度与稀土配合物分子中能量传递过程相关,Er³⁺,Y³⁺离子的引入改变了三元配合物的弛豫过程,且配合物在粉末状态和凝胶状态的弛豫历程不尽相同.结合荧光光谱,从无辐射跃迁和辐射跃迁的角度分析了标题化合物在两种不同固体状态下的发光性质.     

镧系元素Dawson结构钨钒磷四元杂多配合物的合成、表征以及对H2O2分解的催化活性

合成了通式为K₁₅H₃[Ce(P₂W₁₆VO₆₁)₂]·61H₂O、K₁₅H₄[Ln(P₂W₁₆VO₆₁)₂]·xH₂O(Ln=La³⁺,Pr³⁺,Nd³⁺,Sm³⁺,Eu³⁺,Gd³⁺,Dy³⁺,Yb³⁺)的9种镧系元素Dawson结构的钨钒磷四元杂多配合物,并用IR、UV、NMR、ESR、XRD、TG-DTA等对其结构和性质进行了研究。该类配合物具有与K₁₆[Ce(P₂W₁₇VO₆₁)₂]·50H₂O类似的结构,对H₂O₂分解有较高的催化活性。     

系列Sm3+配合物的合成、结构及光物理性能

采用水热方法合成了4种Sm³⁺配合物, 即{[SmZn(2,5-pdc)₂(tp)_0.5(H₂O)]·2H₂O}_n(1), [Sm₂Zn₂(C₆H₅COO)₁₀(Imh)₂(H₂O)₂](2), {[Sm₂(NO₂C₆H₄COO)₆(H₂O)₄]·H₂O}_n(3)和{[SmN(CH₂COO)₃(H₂O)₂]·H₂O}_n(4)[2,5-pdc=2,5-吡啶二羧酸根, tp=对苯二甲酸根, C₆H₅COO=苯甲酸根, Imh=咪唑, NO₂C₆H₄COO=对硝基苯甲酸根, N(CH₂COO)₃=氨三乙酸根]. 通过单晶X射线衍射确定了其晶体结构. 在室温下测定了其红外光谱、 紫外-可见-近红外光谱以及在近红外区和可见区的发射光谱. 结果表明, 4种配合物在近红外区或可见区均出现Sm³⁺离子的特征发射. 这是形成配合物后, Zn-配体部分和配体对Sm³⁺离子发光的敏化作用所致. 此外, 讨论了不同有机配体或d过渡金属离子对Sm³⁺离子发光的影响, 并分析了配合物中Sm³⁺离子的近红外发射带位移、 劈裂和加宽的原因.     

(2-羧基苯氧基)苯-1,2-二羧酸构筑的镧系配合物对苯甲醛和阳离子的荧光传感

采用水热法合成了5个稀土配合物[Sm₂(bdbc)₂(phen)₄](1)和[Ln(bdbc)(phen)(H₂O)][Ln=Eu(2), Gd(3), Tb(4), Dy(5), bdbc=(2-羧基苯氧基)苯-1,2-二羧酸根, phen=1,10-邻菲啰啉]. 配合物1是双核分子, 通过氢键和C—H…π作用进一步构筑成一维超分子结构; 配合物2~5是同构的一维双螺旋结构, 通过氢键和C—H…π作用进一步构筑成三维超分子结构. 配合物1, 2, 4和5呈现了Sm³⁺, Eu³⁺, Tb³⁺和Dy³⁺离子的特征发射, 分别对应于Sm³⁺离子的⁴G_5/2→⁶H_J/2(J=5, 7, 9)、 Eu³⁺离子的⁵D₀→⁷F_J(J=1—4)、 Tb³⁺离子的⁵D₄→⁷F_J(J=6, 5, 4, 3)和Dy³⁺离子的⁴F_5/2→⁶H_J/2(J=15, 13)跃迁. 对配合物4的荧光性质进行了表征, 结果表明, 配合物4可用作荧光探针以检测阳离子和苯甲醛.     

三元体系LaCl3-Am(Am=Gly,Glu,Ser)-H2O(25℃)的研究

测定了3个三元体系LaCl₃-Am-H₂O(Am=Gly,Glu,Ser)在25℃时的溶度和饱和溶液的折光指数。报道了三元体系中生成的三元配合物La(Gly)Cl₃·2H₂O(A₁)、La(Gly)₃Cl₃·3H₂O(A₂)、La₂(Glu)₃Cl₆·8H₂O(C)、La(Ser)Cl₃·3H₂O(E)。用摩尔电导、红外光谱、X射线衍射、热分析及偏光显微镜鉴测定了各配合物的一些物理化学性质。     

Hg(PMBP)2(HPMBP)2和Zn(PMBP)(H2O)Cl配合物的合成及结构

用1-苯基-3-甲基-4-苯甲酰基吡唑啉酮-5(HPMBP)与HgCl₂和ZnCl₂·6H₂O作用,分别合成化学式为[Hg(PMBP)₂(HPMBP)₂]和[Zn(PMBP)(H₂O)Cl]的配合物;用元素分析、IR、¹HNMR和电导等物理化学方法推测了配合物的分子结构式。配体在此螯合过程中皆由酮式转变为烯醇式,在Hg(Ⅱ)配合物中部分不变。     

高氯酸铕的双亚砜配合物研究

本文报告了高氯酸铕的高、低熔点双(正-辛基亚砜)乙烷和双(苯基亚砜)乙烷的四个配合物:Eu(ClO₄)₃(α-BOSE)₃·2H₂O(Ⅰ)、Eu(ClO₄)₃(β-BOSE)₄·2H₂O(Ⅱ)、Eu(ClO₄)₃(α-BPhSE)₃(Ⅲ)和Eu(ClO₄)₃(β-BPhSE)₄·2H₂O(Ⅳ)的合成及性质。     

基于席夫碱配体构筑的LnⅢ2配合物的结构、荧光性质及生物活性

以多齿席夫碱配体H₂L(H₂L=(E)-N′-(3-乙氧基-2-羟基亚苄基)-3-羟基吡啶甲酰肼)为配体,与Ln(acac)₃·2H₂O(Ln=Tb、Ho、Er;acac^-=乙酰丙酮根)反应,通过溶剂热法,成功得到了3例新的双核稀土配合物[Ln₂(acac)₂(L)₂(C₂H₅OH)₂](Ln=Tb((1)、Ho((2)、Er(3))。单晶X射线衍射分析表明：配合物1～3的结构主要由2个Ln^Ⅲ离子、2个乙酰丙酮根(acac^-)、2个L^2-及2个C₂H₅OH组成,中心Ln^Ⅲ离子通过2个μ₂-O原子相互连接,形成一个平行四边形的Ln₂O₂核心。固体荧光实验测...     

Study of lanthanide aromatic acid complexes in silica gels by photoacoustic spectroscopy

Lanthanide complexes Ln(p-ABA)₃·H₂O (p-ABA: p-aminobenzoic acid; Ln³⁺:La³⁺, Tb³⁺ and Er³⁺) have been incorporated into silica gels via a sol–gel method. Upon heat treatment at 120 °C, photoacoustic (PA) intensity of the ligand increases for Tb³⁺, La³⁺ and Er³⁺ complexes in silica gels, respectively, while this difference cannot be observed for the samples without heat treatment. Different PA intensities of the samples are interpreted by comparison with their luminescence spectra. The nephelauxetic parameters and PA branching vectors of Er³⁺ complex in silica gel have been calculated. Spectral results indicate that p-ABA does not coordinate with lanthanide ions in silica matrix without a suitable heat treatment. For the co-doped samples, it is shown that the emissions of Tb³⁺ are enhanced with addition of La(p-ABA)₃·H₂O and remarkably quenched with the addition of Er(p-ABA)₃·H₂O. The possible mechanisms for these phenomena are proposed.     

Syntheses, structures and properties of seven isomorphous 1D Ln3+complexes Ln(BTA)(HCOO)(H2O)3 (H2BTA = bis(tetrazoly)amine, Ln = Pr, Gd, Eu, Tb, Dy, Er, Yb) and two 3D Ln3+ complexes Ln(HCOO)3 (Ln = Pr, Nd)

Seven isomorphous 1D chain Ln3+ complexes Ln(BTA)(HCOO)(H2O)3 (Ln = Pr (1), Gd (2), Eu (3), Tb (4) Dy (5), Er (6) and Yb (7)), and two formate coordinating and bridging 3D Ln3+ complexes Ln(HCOO)3 (Ln = Pr (8) and Nd (9)) have been synthesized and characterized by single crystal X-ray diffraction analysis. Although the Ln3+ ions in 1-7 have different radius, the trivalent lanthanide ions in 1-7 show the same coordinated environment. The well-defined single crystal structures of 8 and 9 are first samples for formate-bridged Ln3+ metallic complexes. The luminescent properties of solid samples of 2-5 at room temperature and the magnetic property of 2 have been also reported and discussed in this paper.     

A series of luminescent lanthanide-cadmium-organic frameworks with helical channels and tubes

Lanthanide (Ln) oxides and cadmium (Cd) salts as sources of metals provided the first series of luminescent Ln-Cd-organic frameworks, [LnCd(imdc)(SO4)(H2O)3].0.5H2O (Ln = Tb, Eu, Dy, Gd, Er, Yb, Y, Nd, Pr; H3imdc = 4,5-imidazoledicarboxylic acid), in which the Ln atoms are linked by imdc ligands with skew coordination orientation, resulting in novel hetero-metallic-organic frameworks with left-/right-handed helical tubes (L1/R1) and channels (L2/R2) along the b axis.     

YAG∶Ce体系中稀土离子掺杂对Ce3+的光谱性能的影响

采用高温固相法合成了一系列的(Y0.95Ln0.01Ce0.04)3Al5O12(简称YAG∶Ce,Ln), 系统地研究了此体系中的Ln3+对Ce3+的发光强度的影响. 结果表明, 在YAG∶Ce的体系中, La3+, Gd3+, Lu3+等光学透明离子的少量掺杂对Ce3+的发光强度的影响不大; 掺入少量的Pr3+, Sm3+, Tb3+, Dy3+, Ho3+, Er3+, Tm3+等稀土离子, 由于它们的能级与Ce3+的能级有交叠, 使它们之间存在着竞争吸收或能量转移, 对Ce3+的发光有较明显的变化, 其中, Pr3+和Sm3+的掺入使其在红光区有发射峰, 可以增加YAG∶Ce的红色成分以提高显色性; Nd3+, Eu3+和Yb3+对Ce3+的发光有严重的猝灭作用.     

Er3+和Ce3+/Ce4+掺杂β-BaB2O4纳米棒的制备、结构与发光性质

以Ba(NO3)2、NaBH4、Er2O3和CeO2为原料, 在十六烷基三甲基溴化铵(CTAB)表面活性剂辅助下, 采用水热法制备了β-BaB2O4 (β-BBO)纳米棒, 稀土离子Er3+单掺杂的β-BBO(β-BBO:Er3+)及Er3+和Ce3+/Ce4+共掺杂的β-BBO(β-BBO:Er3+/Ce3+/Ce4+)纳米棒. 通过X射线粉末衍射(XRD)、傅里叶变换红外(FTIR)光谱、拉曼光谱、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)和光致发光(PL)光谱分别对样品的物相、结构、形貌、成分及光致发光性质进行了表征. 研究结果表明: 微量稀土离子掺杂并不改变β-BBO的结构, 制得的纳米棒尺寸均匀, 长度在200-500 nm 之间, 直径在10-20 nm 之间; β-BBO:Er3+和β-BBO:Er3+/Ce3+/Ce4+纳米棒在400nm光激发下, 在可见光范围内都观察到中心波长为515和542 nm的绿光. 对发光机理的初步研究表明: 发光分别对应于Er3+的2H11/2→4I15/2, 4S3/2→4I15/2跃迁, 铈离子以Ce3+和Ce4+两种形式存在于体系中, Ce3+对Er3+起敏化作用, 可以显著增强β-BBO:Er3+/Ce3+/Ce4+纳米棒的发光强度, 存在Ce3+→Er3+的能量传递过程.     

Highly uniform and monodisperse beta-NaYF(4):Ln(3+) (Ln = Eu, Tb, Yb/Er, and Yb/Tm) hexagonal microprism crystals: hydrothermal synthesis and luminescent properties

beta-NaYF4:Ln3+ (Ln = Eu, Tb, Yb/Er, and Yb/Tm) hexagonal microprisms with remarkably uniform morphology and size have been synthesized via a facile hydrothermal route. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and photoluminescence (PL) spectra as well as kinetic decays were used to characterize the samples. It is found that sodium citrate as a shape modifier introduced into the reaction system plays a critical role in the shape evolution of the final products. Furthermore, the shape and size of the products can be further manipulated by adjusting the molar ratio of citrate/RE3+ (RE represents the total amount of Y3+ and the doped rare earth elements such as Eu3+, Tb3+, Yb3+/Er3+, or Yb3+/Tm3+). Under the excitation of 397 nm ultraviolet light, NaYF4:xEu3+ (x = 1.5, 5%) shows the emission lines of Eu3+ corresponding to 5D0-3 --> 7FJ (J = 0-4) transitions from 400 to 700 nm (whole visible spectral region) with different intensity, resulting in yellow and red down-conversion (DC) light emissions, respectively. When doped with 5% Tb3+ ions, the strong DC fluorescence corresponding to 5D4 --> 7FJ (J = 6, 5, 4, 3) transitions with 5D4 --> 7F5 (green emission at 544 nm) being the most prominent group that has been observed. In addition, under 980 nm laser excitation, the Yb3+/Er3+- and Yb3+/Tm3+-codoped beta-NaYF4 samples exhibit bright green and whitish blue up-conversion (UC) luminescence, respectively. The luminescence mechanisms for the doped lanthanide ions were thoroughly analyzed.     

Synthesis and characterization of heterodinuclear Ln(3+)-Fe3+ and Ln(3+)-Co3+ complexes,bridged by cyanide ligand (Ln3+ = lanthanide ions). Nature of the magnetic interaction in the Ln(3+)-Fe3+ complexes

The reaction of Ln(NO3)3.aq with K3[Fe(CN)6] or K3[Co(CN)6] in N,N'-dimethylformamide (DMF) led to 25 heterodinuclear [Ln(DMF)4(H2O)3(mu-CN)Fe(CN)5].nH2O and [Ln(DMF)4(H2O)3(mu-CN)Co(CN)5].nH2O complexes (with Ln = all the lanthanide(III) ions, except promethium and lutetium). Five complexes (Pr(3+)-Fe3+), (Tm(3+)-Fe3+), (Ce(3+)-Co3+), (Sm(3+)-Co3+), and (Yb(3+)-Co3+) have been structurally characterized; they crystallize in the equivalent monoclinic space groups P21/c or P21/n. Structural studies of these two families show that they are isomorphous. This relationship in conjunction with the diamagnetism of the Co3+ allows an approximation to the nature of coupling between the iron(III) and the lanthanide(III) ions in the [Ln(DMF)4(H2O)3(mu-CN)Fe(CN)5].nH2O complexes. The Ln(3+)-Fe3+ interaction is antiferromagnetic for Ln = Ce, Nd, Gd, and Dy and ferromagnetic for Ln = Tb, Ho, and Tm. For Ln = Pr, Eu, Er, Sm, and Yb, there is no sign of any significant interaction. The isotropic nature of Gd3+ helps to evaluate the value of the exchange interaction.     

Structural and luminescent properties of micro- and nanosized particles of lanthanide terephthalate coordination polymers

Reaction in water between rare earth ions (Ln = Y, La-Tm, except Pm) and the sodium salt of terephthalic acid leads to a family of lanthanide-based coordination polymers of general formula [Ln2(C8H4O4)3(H2O)4] n with Ln = La-Tm or Y. The isostructurality of the compounds with the previously reported Tb-containing polymer is ascertained on the basis of their X-ray powder diffraction diagrams. The coordination water molecules can be reversibly removed without destroying the crystal structure for compounds involving one of the lighter lanthanide ions (La-Eu). For compounds involving one of the heavier lanthanide ions (Tb-Tm) or yttrium, a structural change occurs during the drying process. X-ray diffraction data show this new anhydrous phase corresponding to the linking of pairs of Er(III) ions through mu-carboxylate bridges. Porosity profiles calculated for the anhydrous phases of Tb(III) and Er(III) show the presence of channels with very small sections. The luminescent properties of all the compounds have been recorded and the two most luminescent polymers, namely, the europium- and the terbium-containing ones, have been studied in more detail. Tb(III)-containing compounds display large quantum yields, up to 43%. Polyvinylpyrrolidone nanoparticles doped with [Ln2(C8H4O4)3(H2O)4] n (Ln = Eu, Tb, Er) have also been synthesized and characterized. The encapsulation of the coordination polymers results in somewhat reduced luminescence intensities and lifetime, but the nanoparticles can be dispersed in water and remain unchanged in this medium for more than 20 h.     

Synthesis, characterisation and biological evaluation of lanthanide(III) complexes with 3-acetylcoumarin-o-aminobenzoylhydrazone (ACAB)

Lanthanide(III) complexes of the general formula [Ln(ACAB)(2)(NO(3))(2)(H(2)O)(2)].NO(3).H(2)O where Ln=La(III), Pr(III), Nd(III), Sm(III), Eu(III), Gd(III), Tb(III), Dy(III) and Y(III), ACAB=3-acetylcoumarin-o-aminobenzoylhydrazone have been isolated and characterised based on elemental analyses, molar conductance, IR, (1)H- and (13)C-NMR, UV, TG/DTA and EPR spectral studies. The ligand behaves in bidentate fashion coordinating through hydrazide >C=O and nitrogen of >C=N. A coordination number of ten is assigned to the complexes. Antibacterial and Antifungal studies indicate an enhancement of activity of the ligand on complexation.