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1.
合成了Tb(p-ABA)3·H2O和Ln(p-ABA)3·H2O(p-ABA: 对氨基苯甲酸, Ln: Y或Er)配合物共掺杂的SiO2样品. 荧光光谱测定结果表明, Y(p-ABA)3·H2O的引入增强了样品中Tb3+离子的特征发光, 而Er(p-ABA)3·H2O的引入使Tb3+的发光减弱. 光声光谱结果表明, 与Tb3+配合物单掺的样品相比, Tb3+和Y3+配合物共掺样品的光声强度降低; 而Tb3+和Er3+配合物共掺的样品则情况相反. 实验测定了共掺杂样品的相对量子发光效率和发光寿命, 从无辐射跃迁和辐射跃迁的角度提出共发光效应可能的机制. 结合对室温下陈化干燥样品的分析发现, 只有经适当的热处理过程才能在SiO2凝胶中形成具有多核结构的稀土配合物.  相似文献   

2.
合成了Eu(TTA)3·Phen和Eu0.8Y0.2(TTA)3·Phen固体配合物微晶粉末及其掺杂的SiO2凝胶样品.在300~800nm测定并解释了其光声光谱.在配体吸收处,Eu0.8Y0.2(TTA)3@Phen的光声强度低于Eu(TTA)3@Phen的光声强度;而对于配合物掺杂的凝胶样品,则情况相反.Y3+的引入改变了配合物的弛豫过程,且配合物在粉末和凝胶状态下,弛豫历程不尽相同.结合荧光光谱研究了标题化合物的发光特性,并建立了能量传递模型.  相似文献   

3.
高氯酸铕的双亚砜配合物研究   总被引:2,自引:0,他引:2  
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。  相似文献   

4.
高氯酸二甘氨酸十二水合二铒的晶体结构   总被引:1,自引:1,他引:0  
在水溶液中合成了甘氨酸铒配合物[Er2(Gly)2(H2O)12](ClO4)6·4H2O单晶,并测定了其晶体结构。该晶体属单斜晶系,P21/n空间群。晶胞参数:a=1.0571(2)nm,b=1.0837(2)nm,c=1.7728(4)nm,β=90.09(3)°,V=2.0309(7)nm2,Z=2,Dc=2.239g/cm3.最终偏差因子R=0.055,Rw=0.061.每2个Er3+离子由2个甘氨酸羧基桥联成双核结构。Er3+离子还与6个水分子的氢原子配位,形成畸变的四方棱柱型配位多面体。  相似文献   

5.
Chiroptical switches based on circularly polarized luminescence(CPL) have shown the promising applications in advanced information technologies. Herein, a pair of lanthanide coordination polymer enantiomers [Eu2(LR)3(BTFPO)2]n and [Eu2(LS)3(BTFPO)2]n with light-regulated CPL property are designed,which are assembled by a chiral binuclear triple-stranded Eu3+ helicates [Eu...  相似文献   

6.
合成了5种通式为(NH4)15[RE(PMo9V2O39)2]·xH2O(RE=La3+,Ce3+,Gd3+,Y3+,Yb3+)的稀土钼钒磷四元杂多配合物,并用IR,UV,XRD,ICP,TG-DTA和CV等手段对其结构和性能进行了表征.催化活性实验表明,标题化合物对苯酚过氧化氢羟化制苯二酚反应有良好的催化活性.  相似文献   

7.
合成了1,10-菲哆啉-1-氧化物(PhenNO)的稀土配合物RE2(PhenNO)6(Ac)2(ClO4)4·3H2O(RE=Eu,Gd,Tb,Ho,Er,Yb;Ac=乙酸根),经元素分析确定了配合物的组成,探讨了配合物的组成和结构对荧光性质的影响.  相似文献   

8.
合成了一种新的氧化膦取代杯芳烃衍生物的稀土离子(La3+,Eu3+)硝酸盐配合物.通过元素分析和红外光谱对配合物进行了表征.在无水甲醇中培养出了配合物的单晶,用X射线单晶衍射法测定了其晶体结构.硝酸镧配合物晶体[L·La(OH2)(NO3)2]NO3{L为四(亚甲基二苯基氧化膦)杯[4]芳烃}属四方晶系,空间群P43212,晶胞参数a=b=1.8977(4)nm,c=3.1087(11)nm;Z=4;V=11.196(5)nm3;Dc=1.097g/cm3,F(000)=3712,μ=0.491mm-1,R1=0.1181,wR2=0.1930.硝酸铕配合物晶体[L·Eu(OH2)(NO3)2]NO3·CH3OH属单斜晶系,空间群C2/c,晶胞参数a=2.88172(11)nm,b=5.4015(2)nm,c=2.01189(7)nm;β=133.4067(9)°,Z=8;V=22.7511(14)nm3,Dc=1.106g/cm3,F(000)=7464,R1=0.0671,wR2=0.1794.2个配合物的晶体结构相类似,配合物中配体的4个磷氧键上的氧原子、2个双齿配位的硝酸根中的4个氧原子还有1个水分子中的氧原子分别参与了配位.中心离子配位数为9,配位多面体为单帽四方反棱柱体.另外在铕配合物的杯芳烃中还包合了1个甲醇分子.  相似文献   

9.
研究了溶液中杯[4]芳烃双冠-6(BisC6)与Cs+配位行为.常温下,BisC6/NPME(邻硝基苯甲醚)体系单级萃铯百分率达99.36%,模拟料液中,Cs+/Na+和Cs+/K2+分离系数分别为3.92×104和2.21×104.局域结构模型实验表明,配合物分子中可能存在水或(和)硝酸(根).ESI-MS谱表明,NPME体系中,铯离子与BisC6同时形成1:1(单核)和2:1(双核)的配合物,并且存在[BisC6·H2O],[BisC6·Cs+]+,[BisC6·2Cs+·H2O]2+和[BisC6·2Cs10+·No10-3]10+等多种配合物分子.EXAFS实验表明,溶液中铯离子的配位数为7,形成7个氧配位的稳定结构,ADF计算验证了EXAFS实验结果.  相似文献   

10.
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。  相似文献   

11.
Solid complexes Ln(Sal)3.H2O (Sal: salicylic acid; Ln: La3+, Nd3+, Eu3+, Tb3+) are synthesized, and their photoacoustic (PA) spectra in the UV-Vis region have been recorded. PA intensities of central lanthanide ions are interpreted in terms of the probability of nonradiative transitions. It is found that PA intensity of the ligand increases in the order of Tb(Sal)3.H2O < La(Sal3).H2O < Eu(Sal)3.H2O < Nd(Sal)3.H2O. Different PA intensities of the ligand are interpreted by comparison with the fluorescence spectra. Ternary complexes Eu(Sal)3Phen and Tb(Sal)3Phen (Phen: 1,10-phenanthroline) are synthesized. Compared with their binary complexes, PA intensity of the ligand Sal decreases for Eu(Sal)3Phen, while the reverse is true for that of Tb(Sal)3Phen. The luminescence of Eu3+ increases remarkably when Phen is introduced, and luminescence of Tb3+ decreases greatly when Phen is added. The intramolecular energy transfer and relaxation processes in the complexes are discussed from two aspects: radiative and nonradiative relaxations.  相似文献   

12.
合成了13种1,5-双(1′-苯基-3′-甲基-5′-吡唑啉酮-4′)-戊二酮-[1,5](BPMPPD)和溴化十六烷基吡啶盐(CPB)的稀土配合物.研究了配合物的红外光谱、紫外可见光谱、差热-热重谱、荧光光谱、核磁共振谱及摩尔电导等性质,发现配合物属离子型缔合物CP+[Ln(BPMPPD)2]-.Pr、Nd、Ho、Er、Tm配合物发生超灵敏跃迁.配合物的热分解温度具有"四分组"效应,Sm、Eu、Tb、Oy为线性荧光。  相似文献   

13.
A new simple method of synthesis of heteroligand complexes [Ln(Dalkdtc)3Phen] (Ln = Eu or Er; Dalkdtc is the dialkyldithiocarbamate ion, Phen is o-phenanthroline) in an aqueous solution is described; the possibility of using the complexes as initial reagents for the synthesis of rare-earth sulfides is shown.  相似文献   

14.
利用缺位填充法合成了12个γ-[SiW10O36]8-夹心型稀土元素单取代多酸化合物K13[Ln(SiW10O36)2]·nH2O(Ln=La3+,Ce3+,Pr3+,Nd3+,Sm3+,Eu3+,Gd3+,Tb3+,Dy3+,Ho3+,Er3+,Yb3+).通过元素分析确定其组成,由红外光谱、紫外-可见吸收光谱、循环伏安及室温磁化率测定结果确认稀土离子与γ-[SiW10O36]8-相配位;183WNMR及荧光光谱结果则表明,稀土离子处于2个γ-[SiW10O36]8-构成的八配位环境中,标题化合物具有夹心型D2d对称性结构.  相似文献   

15.
A series of dinuclear complexes of salicylic acid (HSal) and o-phenanthroline (Phen) with different molar ratios of Eu3+ to Y3+ have been synthesized. Their compositions are Eu(x)Y(1-x) (Sal)3(Phen) (x = 0 to approximately 1). Their UV spectra, IR spectra, and fluorescence spectra were studied. The UV spectra of the complexes reflect essentially absorption of the ligands for the fact that no obvious change of wavelength and band shape is found between the spectra of the complexes and that of the ligands except slight red shift. The IR absorption spectra indicate that salicylic acid is coordinated to the rare earth ions and chemical bonds are formed between rare earth ions and nitrogen atoms of o-phenanthroline. The fluorescence spectra of the complexes indicate that the fluorescence emission intensity of europium ion was enhanced by the addition of Y3+, which is referred to as cofluorescence. These facts show that not only the ligands but also the yttrium complex can transfer the absorbed energy to Eu3+ ion in the complexes. Formation of polynuclear complexes appears to be responsible for cofluorescence.  相似文献   

16.
Li C  Quan Z  Yang J  Yang P  Lin J 《Inorganic chemistry》2007,46(16):6329-6337
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.  相似文献   

17.
Optical spectroscopy of lanthanide ions in ZnO-TeO2 glasses   总被引:2,自引:0,他引:2  
Zinc tellurite glasses of compositions 19ZnO-80TeO2-1Ln2O3 with Ln = Eu, Er, Nd and Tm were prepared by melt quenching. The absorption spectra were measured and from the experimental oscillator strengths of the f-->f transitions the Judd-Ofelt parameters ohm(lambda) were obtained. The values of the ohm(lambda) parameters are in the range usually observed for oxide glasses. For Nd3+ and Er3+, luminescence spectra in the near infrared were measured and the stimulated emission cross sections sigma(p) were evaluated for some laser transitions. The high values of sigma(p), especially for Nd3+, make them possible candidates for optical applications. Fluorescence line narrowing (FLN) spectra of the Eu3+ doped glass were measured at 20 K, and the energies of the Stark components of the 7F1 and 7F2 states were obtained. A crystal field analysis was carried out assuming a C2v site symmetry. The behaviour of the crystal field ratios B22/B20 and B44/B40 agrees reasonably well with the values calculated using the geometric model proposed by Brecher and Riseberg. The crystal field strength at the Eu3+ sites appears to be very low compared to other oxide glasses.  相似文献   

18.
本文报导了Tb,Eu,La与邻氨基苯甲酸(o-AA)或N-苯基邻氨基苯甲酸(N-PAA)及邻菲啡啰啉(Phen)形成的固态三元配合物。通过元素分析,热谱分析和摩尔电导测定确定该类配合物的组成为Ln(Phen)(L)3(Ln=Tb、Eu、La,L=o-AA或N-PAA),考察了这类配合物的红外光谱、UV吸收光谱、核磁共振谱和x光电子能谱,确定其配位形式,并讨论了它们的发光性质。  相似文献   

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