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1.
异核稀土双亚砜配合物的合成、表征和荧光性质   总被引:2,自引:1,他引:2  
合成得到一系列异核土双乙烷配合物和异核稀土双乙烷与1,10-啡咯啉的配合物,通过元素分析,电感耦合等离子体法,电导,红外和紫外光谱对配合进行了表征,并研究了这些配合物的固体和溶液的荧光光谱。  相似文献   

2.
Two europium trifluoroacetate complexes, Eu(CF3COO)3·phen ( 1 ) and Eu(CF3COO)3·bpy ( 2 ) (where phen=1,10‐phenanthroline, bpy=2,2′‐bipyridine), were synthesized and characterized by elemental analysis, Fourier transform infrared spectroscopy (FT‐IR), photoluminescence (PL) spectroscopy and thermogravimetric analysis (TA). Single‐crystal X‐ray structure has been determined for the complex [Eu2(CF3COO)6·(phen)3·(H2O)2]·EtOH. The crystal structure of [Eu2(CF3COO)6·(phen)3·(H2O)2]·EtOH shows that two different coordination styles with europium ions coexist in the same crystal and have entirely different coordination geometries and numbers. This crystal can be considered as an 1:1 adduct of [Eu(CF3COO)3·(Phen)2·H2O]·EtOH (9‐coordination part) and Eu(CF3COO)3·phen·H2O (8‐coordination part). The excitation spectra of the two complexes demonstrate that the energy collected by "antenna ligands" is transferred to Eu3+ ions efficiently. The room‐temperature PL spectra of the complexes are composed of the typical Eu3+ ions red emission, due to transitions between 5D07FJ(J=0→4). The lifetimes of 5D0 of Eu3+ in the complexes were examined using time‐resolved spectroscopic analysis, and the lifetime values of Eu(CF3COO)3·phen and Eu(CF3COO)3·bpy were fitting with bi‐exponential (2987 and 353 µs) and monoexponential (3191 µs) curves, respectively. In order to elucidate the energy transfer process of the europium complexes, the energy levels of the relevant electronic states had been estimated. The thermal analyses indicate that they are all quite stable to heat.  相似文献   

3.
Two novel ligands N‐Benzyl‐2‐{2′‐[(benzyl‐phenyl‐carbamoyl)‐methoxy]‐[1,1′]binaphthalenyl‐2‐yloxy}‐N‐phenyl‐acetamide (L1) and N‐Methyl‐2‐{2′‐[(methyl‐phenyl‐carbamoyl)‐methoxy]‐[1,1′]binaphthalenyl‐2‐yloxy}‐N‐phenyl‐acetamide (L2), and their europium(III) complexes with picrate, [Eu(pic)3(L1)] and [Eu(pic)3(L2)], were synthesized and characterized by elemental analysis, IR, UV‐Vis and fluorescence spectroscopy. The crystal structure of [Eu(pic)3(L1)]·2CHCl3 was determined by single crystal X‐ray diffraction. The europium atom is coordinated by nine oxygen atoms of four from the L1 and five from two bidentate and one unidentate picrates. The fluorescent intensity of [Eu(pic)3(L2)] is about 2.6 times that of [Eu(pic)3(L1)] in solid states. But in CHCl3 solution, the fluorescent intensity of [Eu(pic)3(L1)] is stronger slightly than [Eu(pic)3(L2)].  相似文献   

4.
分别制备了二氧化硅壳层厚度为10、25和80 nm的三种Ag@S O2纳米粒子,合成了铕与不同比例苯甲酸根(BA)的配合物、铕与1,10-邻菲罗啉(phen)及2,2′-联吡啶(bpy)的配合物,并对其进行表征.表征结果推测配合物的组成为Eu(BA)nCl3-n·2H2O(n=1,2,3)、Eu(phen)Cl3·2H2O和Eu(bpy)Cl3·2H2O.配合物的荧光光谱显示,在加入Ag@Si O2纳米粒子后,复合物的荧光强度有不同程度的增加,这可能是由于表面等离子体共振造成的.不同硅壳厚度的Ag@Si O2纳米粒子的荧光增强顺序是25 nm80 nm10 nm,这表明二氧化硅核壳厚度约25 nm时有较强的表面等离子体共振效应.此外,在这些复合物中,Eu(phen)Cl3·2H2O复合物的增强效果是最强的,而Eu(BA)nCl3-n·2H2O的增强效果是最弱的.在三个苯甲酸铕配合物中,Eu(BA)3·2H2O的增强效果最弱,其他两个苯甲酸铕复合物增强效果相对较好.原因可能是含氮配合物(Eu(phen)Cl3·2H2O和Eu(bpy)Cl3·2H2O)可以和Ag@SiO2更好地成键,而苯甲酸铕配合物和Ag@Si O2纳米粒子的作用相对较弱.Ag@SiO2纳米粒子有望应用于增强稀土材料的发光.  相似文献   

5.
Three new gallium complexes formulated as [Ga(PDA)2][Ga(H2O)(PDA)(phen)]·4H2O(1), [Ga(PDA)2]· (H2IN)·2H2O(2) and [Ga(OH)(PDA)(H2O)]2(3)(H2PDA=pyridine-2,6-dicarboxylic acid; phen=1,10-phenanthroline; HIN=isonicotinic acid) have been synthesized under hydrothermal conditions. In the mixed-ligand system of complex 1, PDA2? and phen are connected to the central Ga3+ cation as tri- and bi-dentate ligands, respectively. In complex 2, each Ga3+ cation is six-coordinated by two PDA2? anions octahedrally. Complex 3 shows a binuclear structure, with the bond distance of Ga1-Ga2 being 0.30061(3) nm. The 3D supramolecular structures of the three complexes are constructed via hydrogen bonds and aromatic π-π packing interactions. All the three complexes exhibit intense blue emission at room temperature in the solid state, which are attributed to π*-π transition centered on the ligands.  相似文献   

6.
A set of four luminescent EuIII complexes bearing an extended aryl-alkynylpyridine chromophore has been studied, showing very different pH-dependent behaviour in their absorption and emission spectral response. For two complexes with pKa values of 6.45 and 6.20 in protein-containing solution, the emission lifetime increases very significantly following protonation. By varying the gate time during signal acquisition, the ‘switch-on’ intensity ratio could be optimised, and enhancement factors of between 250 to 1330 were measured between pH 8 and 4. The best-behaved probe showed no significant emission dependence on the concentration of endogenous cations, reductants, and serum albumin. It was examined in live-cell imaging studies to monitor time-dependent lysosomal acidification, for which the increase in observed image brightness due to acidification was a factor of 50 in NIH-3T3 cells.  相似文献   

7.
A europium salt-Na[Eu(5,5′-DMBP)(phen)3]·Cl3 (Eu(III)-CPLx) was prepared by using various precursors such as 5,5′-Dimethyl-2,2′-bipyridyl (5,5′-DMBP), 1,10-phenanthroline (phen) and europium chloride hexahydrate (EuCl3·6H2O) by a complexation method. The red emission fluorescent Na[Eu(5,5′-DMBP)(phen)3]·Cl3/D-Dextrose (Eu(III)-CPLx/D-Dex) composite was synthesized by using an adsorption method with Eu(III)-CPLx and D-Dextrose (D-Dex). The Eu(III)-CPLx and fluorescent (Eu(III)-CPLx/D-Dex) composites were characterized by numerous techniques. The fluorescent (Eu(III)-CPLx/D-Dex) composite demonstrated a strong red emission and controlled fluorescence quenching in the solid state and was consequently used in latent fingerprint (LFP) detection. The LFPs were developed by using a powder dusting method (PDM) with Eu(III)-CPLx and fluorescent Eu(III)-CPLx/D-Dex composites on different substrates under daylight and UV-light irradiation at 365 nm. The fluorescent Eu(III)-CPLx/D-Dex composite was effectively explored for developing LFP images on various substrates and also acts as a better labeling agent for LFP detection in forensic science crime scene investigations.  相似文献   

8.
采用密度泛函理论(DFT)和含时密度泛函理论(TD-DFT)方法计算了4种N,N-B螯合物1,1q,2和2q的基态和激发态结构、吸收和发射光谱、跃迁密度矩阵、分子内电荷转移特征、黄昆(HR)因子、FranckCondon因子和电子耦合等光物理性质,深入探究化合物1q和2q在几何结构微调后发光效率降低的本质原因.计算结果表明,N,N-B螯合物中喹啉取代吡啶,以及吲哚配体中N杂原子的引入对光物理性质产生了较大影响.相比于化合物1和2,化合物1q和2q由于共轭面的扩展导致HOMO-LUMO能隙变窄,使吸收红移.通过计算HR因子和跃迁密度矩阵对激发态的特征和几何弛豫进行分析,结果表明化合物1q和2q具有明显增强的片段间电荷转移特征,发射能和振子强度减弱导致kr减小,并且激发态和基态间的电子耦合急剧增强造成快速的非辐射衰变,导致化合物1q和2q在CH2Cl2溶液中不发光.同时,化合物1和2具有高效的发光效率和较大的斯托克斯位移,是一类有发展前景的发光材料.  相似文献   

9.
本文报道了MSnO_3∶Eu~(3+)和M_2SnO_4∶Eu~(3+)(M=Ca,Sr,Ba)体系荧光粉的合成和荧光性质。产品经X射线确证CaSnO_3∶Eu~(3+)和Ca_2SnO_4∶Eu~(3+)为正交晶系,SrSnO_3∶Eu~(3+)和BaSnO_2∶Eu~(3+)为立方晶系,而Sr_2SnO_4∶Eu~(3+)和Ba_2SnO_4∶Eu~(3+)为四方晶系。激发光谱表明,随Ba—Sr—Ca离子半径减小,Eu~(3+)的电荷迁移能量紫移,而Eu~(3+)的f-f跃迁红移。发射光谱表明,CaSnO_3∶Eu~(3+)和Ca_2SnO_4∶Eu~(3+)以电偶极跃迁为主,而其它4种化合物不存在电偶极跃迁。  相似文献   

10.
张建军  王瑞芬 《分析化学》2001,29(10):1209-1212
用TG-DTG技术研究了对氯苯甲酸铕与邻菲咯啉络合物在静态空气中的热分解,用Coats-Redfern(CR)法、Horowitz-Metzger(HM)法、Madhusudanan-Krishnan-NInan(MKN)法、Ozawa法和Kissinger法计算了对氯苯甲酸铕与邻菲咯啉络合物第一步热分解反应的动力学参数活化能(E)、指前因子(A)、反应级数(n)等。用等温TG法得到失重10%的E、A值和寿命方程:lnτ=-23.0189 17974.1/T。  相似文献   

11.
制备了掺Er3+重金属氧氟硅酸盐玻璃,研究了玻璃的吸收光谱和荧光光谱性质,应用Judd Ofelt理论计算了强度参数Ωt(t=2,4,6)、Er3+离子的振子强度、自发辐射跃迁几率、荧光分支比和辐射寿命等光谱参数。应用McCumber理论,计算了能级4I13 2→4I15 2跃迁的受激发射截面。结果表明:掺Er3+重金属氧氟硅酸盐玻璃具有较宽的荧光半高宽和较大的受激发射截面。对Er3+离子在不同玻璃基质中带宽特性的比较发现,掺Er3+重金属氧氟硅酸盐玻璃的带宽特性与碲酸盐和铋酸盐玻璃相当,大于磷酸盐、锗酸盐和硅酸盐玻璃。  相似文献   

12.
铕-结晶紫缔合物分光光度法测定痕量铕   总被引:1,自引:0,他引:1  
在碱性(pH10.10)条件下,铕(Ⅲ)与结晶紫形成缔合物,表观摩尔系数为=1.8×105L/(mol.cm),铕的浓度在0.15~1.2mg/l范围内遵守比耳定律,组成摩尔比为Eu∶CV=1∶2.  相似文献   

13.
菲咯啉类有机钌络合物的合成及其光谱分析   总被引:1,自引:0,他引:1  
近年来,为寻找性能更优良的荧光材料人们作了很多努力,在有机过渡金属化合物研究方面,取得了较大进展[1,2].  相似文献   

14.
菲咯啉类有机钌铬合物的合成及其光谱分析   总被引:3,自引:0,他引:3  
  相似文献   

15.
分别制备了二氧化硅壳层厚度为10、25和80 nm的三种Ag@SiO2纳米粒子, 合成了铕与不同比例苯甲酸根(BA)的配合物、铕与1, 10-邻菲罗啉(phen)及2, 2''-联吡啶(bpy)的配合物, 并对其进行表征. 表征结果推测配合物的组成为Eu(BA)nCl3-n·2H2O (n=1, 2, 3)、Eu(phen)Cl3·2H2O和Eu(bpy)Cl3·2H2O. 配合物的荧光光谱显示, 在加入Ag@SiO2纳米粒子后, 复合物的荧光强度有不同程度的增加, 这可能是由于表面等离子体共振造成的. 不同硅壳厚度的Ag@SiO2纳米粒子的荧光增强顺序是25 nm>80 nm>10 nm, 这表明二氧化硅核壳厚度约25 nm时有较强的表面等离子体共振效应. 此外, 在这些复合物中, Eu(phen)Cl3·2H2O复合物的增强效果是最强的, 而Eu(BA)nCl3-n·2H2O的增强效果是最弱的. 在三个苯甲酸铕配合物中, Eu(BA)3·2H2O的增强效果最弱, 其他两个苯甲酸铕复合物增强效果相对较好. 原因可能是含氮配合物(Eu(phen)Cl3·2H2O和Eu(bpy)Cl3·2H2O)可以和Ag@SiO2更好地成键, 而苯甲酸铕配合物和Ag@SiO2纳米粒子的作用相对较弱. Ag@SiO2纳米粒子有望应用于增强稀土材料的发光.  相似文献   

16.
Lanthanide complex-based luminescent probes/chemosensors have shown great utilities in various biological and environmental assays with time-resolved detection mode to eliminate background noises. In this work, by conjugating di(2-picolyl)amine (DPA) with a tetradentate β-diketone 1,2-bis[4'- (1",1",1",2",2"-pentafluoro-3",5"-pentanedion-5"-yl)benzyl]-4-chlorosulfo-benzene (BPPBCB), a novel dual-functional ligand that can coordinate to Eu3+ for responding to Cu2+ and S2- ions in aqueous media, DPA-BPPBCB, has been designed and synthesized. The β-diketone moiety of DPA-BPPBCB can form a strongly luminescent complex with Eu3+. Upon reaction with Cu2+, accompanied by the formation of heterobimetallic complex Cu2+-DPA-BPPBCB-Eu3+, the Eu3+ luminescence was quenched. While in the presence of S2-, owing to the high affinity of S2- to Cu2+, stable CuS was formed, which resulted in the release of Cu2+ from Cu2+-DPA-BPPBCB-Eu3+, to restore the luminescence of the Eu3+ complex. This unique “on-off-on” luminescence response of the Eu3+ complex enabled Cu2+ and S2- ions in aqueous media to be detected with time-resolved luminescence detection mode.  相似文献   

17.
蔡静  曾薇  李权  骆开均  赵可清 《化学学报》2009,67(20):2301-2308
使用含时密度泛函理论(TDDFT)B3LYP方法计算了IB, IIB, VIIIB过渡金属与8-羟基喹啉络合(MQ)后, 配合物的电子光谱以及二阶非线性光学性质. 结果表明, 掺杂过渡金属后, 形成络合物的能隙值减小100~150 kJ/mol, 最大吸收波长红移150~200 nm左右. 电子从基态到激发态的跃迁主要为p→p*, n→p*跃迁, 属于LLCT, MLCT过程. IB的络合物MQ以及VIIIB的络合物MQ3表现出良好的非线性光学性质.  相似文献   

18.
The UV, excitation, and luminescence spectra of tris(pivaloyltrifluoroacetonato)europium(III) ([Eu(pta)3]; Hpta=1,1,1‐trifluoro‐5,5‐dimethylhexane‐2,4‐dione=HA) were measured in the presence of bis(salicylidene)trimethylenediamine (H2saltn), bis[5‐(tert‐butyl)salicylidene]trimethylenediamine (H2(tBu)saltn), or bis(salicylidene)cyclohexane‐1,2‐diyldiamine (H2salchn), and the corresponding ZnII complexes [ZnB] (B=Schiff base). The excitation and luminescence spectra of the solution containing [Eu(pta)3] and [Zn(salchn)] exhibited much stronger intensities than those of solutions containing the other [ZnB] complexes. The introduction of a tBu group into the Schiff base was not effective in sensitizing the luminescence of [Eu(pta)3]. The luminescence spectrum of [ZnB] showed a band around 450 nm. The intensity decreased in the presence of [Eu(pta)3], reflecting complexation between [Eu(pta)3] and [ZnB]. On the basis of the change in intensity against the concentration of [ZnB], stability constants were determined for [Eu(pta)3Zn(saltn)], [Eu(pta)3Zn{(tBu)saltn}], and [Eu(pta)3Zn(salchn)] as 4.13, 4.9 and 5.56, respectively (log , where =[[Eu(pta)3ZnB]]([[Eu(pta)3]][[ZnB]])?1). The quantum yields of these binuclear complexes were determined as 0.15, 0.11, and 0.035, although [Eu(pta)3Zn(salchn)] revealed the strongest luminescence at 613 nm. The results of X‐ray diffraction analysis for [Eu(pta)3Zn(saltn)] showed that ZnII had a coordination number of five and was bridged with EuIII by three donor O‐atoms, i.e., two from the salicylidene moieties and one from the ketonato group pta.  相似文献   

19.
The molecular structures of the ground and the lowest triplet states for a series of Pt(II) complexes PtLCl(1)[L=6-(2-hydroxyphenyl)-2,2′-bipyridine], Pt(pp)2[pp=2-(2-hydroxyphenyl)pyridine](2), PtbpyCl2(bpy=2,2′- bipyridine)(3), and the free tridentate L ligand(4) were optimized by the density functional theory B3LYP and UB3LYP methods, respectively. On the basis of optimized geometries, the spectral properties were investigated with time-dependent density functional theory(TD-DFT). In comparison with those of complexes 2 and 3, the more rigid structure of complex 1 together with its low rate of the radiationless decay via nonemissive d-d state leads to higher photoluminescence quantum efficiency. And the phosphorescence quantum efficiency of complex 1 can be easily controlled by modifying auxiliary ligands. The introduction of fluorine ligand into complexes can effectively increase the radiation transition rate and decrease the radiationless d-d transition rate, and as a result, a novel complex PtLF(5) might be a good phosphorescent material suitable for organic electronic devices.  相似文献   

20.
磷光软盐配合物是一种通过静电力和范德华力结合的带有相反电荷金属配合物的光电材料,它们的发射光谱通常由两个独立部分组成.与单组分磷光金属配合物相比,磷光软盐配合物含有更丰富的激发态,不同组分之间还存在能量传递过程.最近几年,磷光软盐配合物作为一类新兴的光电材料,在不同的光电领域表现出潜在的应用前景,并取得了一定的进展.本综述详细介绍了磷光软盐的合成与光物理性质,并对它们在有机发光二极管、生物成像、光动力治疗、电致发光变色等领域的应用进行了总结.  相似文献   

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