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1.
Rare earth (RE) ternary complexes of Eu0.5Ln0.5(NPPD)3·(DPQ) (HNPPD=1-(naphthalen-2-yl)-3-phenylpropane-1,3-dione; DPQ= dipyridobenzoquinone) and Eu1-xLax(NPPD)3·(DPQ) (Ln3+=La3+, Gd3+, Sm3+, Pr3+; x=0.0, 0.1, 0.3, 0.5, 0.7, 0.9) were synthesized by the reaction of RECl3·6H2O with HNPPD and DPQ in stoichiometry. The complexes were characterized with IR, elemental analysis, TGA-DSC and wide-angle X-ray diffraction. The UV-Vis absorption spectra and fluorescence properties of the complexes were also investigated. The experimental results showed that the luminescence efficiency of Eu3+ complexes was enhanced by doping some other lanthanide ions. Eu0.7La0.3(NPPD)3·(DPQ) showed the highest luminescence efficiency.  相似文献   

2.
Themetalcomplexesofhydrazideshaveattractedconsiderableinterestowingtotheirantifungalandantibacterialactivities[1 ,2 ] .Theycanalsobeusedasanalyticalreagents[3 ]andextractingagentsformetalsalts[4 ] .Manycomplexesofhydrazideshavebeensynthesizedandcharacterized[5]…  相似文献   

3.
Rareearthcomplexeswithsulfoxideandaromaticcarboxylacidhavebeenwidelystud ied[1~ 3 ] .Itisprovedthattheybothhavebet terfluorescencecharacter .Howeverthearo maticcarboxylofrareearthcomplexeshaveveryhighfluorescenceemissionintensityandstability ,butsolubilityi…  相似文献   

4.
The complexes of 3-methoxy-2-nitrobenzoates of Pr(III), Nd(III), Sm(III), Eu(III), Gd(III), Tb(III), Er(III) and Tm(III) with the formula: Ln(C8H6NO5)3·2H2O, where Ln=lanthanides(III), were synthesized and characterized by elemental analysis, Forier transform irtrared (FTIR) spectroscopy, magnetic and thermogravimetric studies and also by X-ray diffraction (XRD) measurements. The complexes had col- ours typical for Ln(III) ions. The carboxylate groups bound as bidentate chelating. On heating to 1173 K in air they decomposed in the same way, at first, dehydrated in one step to anhydrous salts, and then decomposed to the oxides of respective metals with intermediate formation of the oxycarbonates. The enthalpy values of the dehydration process changed from 133.72 to 44.50 kJ/mol. Their solubility in water at 293 K was of the order of 10-4 mol/dm3. The magnetic moments of analysed complexes were determined by Gouy’s method in the range of 76-303 K.  相似文献   

5.
The two compounds of [Ln(2-FBA)3·2,2'-bpy]2 (2-FBA=2-fluorobenzoato, 2,2'-bpy=2,2'-bipyridine, Ln=Eu(1), Dy(2)) were synthesized and their structures were determined by X-ray diffraction method. Crystallized complexes 1 and 2 are isomorphous, monoclinic system with P21/n space group. The two complexes are binuclear molecule with an inversion center. The two lanthanide ions are linked by four bridged 2-FBA ligands and each lanthanide ion is further bonded to one chelated bidentate 2-FBA ligand and one 2,2'-bipyridine molecule. The coordination number of metal ion is eight. The europium complex exhibits strong red fluorescence. 5D0→7Fj (j= 1~4) transition emission of Eu3 ion was observed.  相似文献   

6.
Four lanthanide coordination complexes, namely, [Ln(2,3-DClBA)_3(5,5'-dmebipy)(H_2O)]_2(Ln=Sm(1), Eu(2), Dy(3), Ho(4)); 2,3-DClBA=2,3-dichlorobenzoate; 5,5'-dmebipy=5,5'-dmethylbipyridine) were synthesized and characterized by elemental analysis, infrared spectroscopy and single crystal X-ray diffraction. Findings indicated that complex 3 was a dinuclear molecule, and the center Dy~(3+) was eight-coordinated. Each dinuclear units could be connected by H bond and halogen-halogen interactions. Luminescent property of complex 2 suggested the typical intense emissions of Eu~(3+) ions. Thermal analysis showed that the complexes decomposed in three steps: the coordination water was lost firstly then the neutral ligand 5,5'dmebipy was lost and lastly the 2,3-DClBA ligand was lost.  相似文献   

7.
双水杨醛1,6-己二胺希夫碱轻稀土配合物的合成和表征   总被引:4,自引:0,他引:4  
合成并表征了双水杨醛缩 1,6 己二胺希夫碱配体 (C2 0 H2 4 N2 O2 ,以L表示 )与轻稀土Ln3 的 7种新的固体配合物 [LnL2 ](NO3) 3(Ln =La、Ce、Pr、Nd、Sm、Eu、Gd)。利用元素分析、摩尔电导、红外光谱、电子光谱、X射线衍射物相分析、热分析方法进行表征。中心金属离子Ln3 与希夫碱配体中的亚胺氮和酚羟基中的氧发生配位 ,配位数为 8。  相似文献   

8.
A novel technique for YAG:Ln (Ln=Eu, Ce) phosphor powder synthesis with a nanocrystalline structure was developed. Nanocrystalline YAG:Ln powder was prepared by an ultrasonic atomization and co-precipitation method using a mixture solution of ammonium hydroxide(NH3·H2O) and ammonium hydrogen carbonate(NH4HCO3) as precipitant. The as-prepared nano-powders were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and fluorescence spectrometer. The obtained phosphor powders were homogenous and in size of 50-70 nm. The results demonstrated that by using ultrasonic atomization and co-precipitation process, we could synthesize a good quality YAG:Ln (Ln=Eu, Ce) phosphor powder that had many potential applications.  相似文献   

9.
合成了稀土硝酸盐与双希夫碱邻香兰素缩邻苯二胺(以L表示)的3种新固体配合物。通过元素分析、红外光谱、紫外光谱、差热一热重、摩尔电导及X射线粉末衍射分析等手段,确定配合物的组成为(LnL(NO3)2)NO3(Ln=Nd、Sm、Eu)。并对其结构和某些物理化学性质进行了研究。  相似文献   

10.
Three coordination polymers, Ln2(bpdc)3(phen)2(H2O)2 (Ln=Nd(1), Eu(2), and Tb (3); bpdc=2,2'-bipyridine-3,3'-dicarboxylate; phen=1,10-phenanthroline), were obtained by hydrothermal reaction of Ln2O3 with 2,2'-bipyridine-3,3'-dicarboxylate acid, and 1,10-phe- nanthroline. They were characterized by single-crystal X-ray diffraction, IR spectra, and photoluminescent spectra. The crystallographic data of 1-3 indicated that they were isostructural. Both complexes contained paddle-wheel building blocks, formed by bpdc and phen ligands. These paddle-wheel secondary building units (SBUs) were further connected to form two-dimensional (2-D) metal organic framework (MOF) networks by 2,2'-bipyridine-3, and 3'-dicarboxylate tinkers. A three-dimensional (3-D) supramolecular structure was formed by π-π aromatic interactions between adjacent 2-D infinite networks. Photoluminescent measurements indicated that europium compound 2 and terbium compound 3 were strong, red and green emitters, respectively.  相似文献   

11.
A novel technique for YAG:Ln(Ln=Eu,Ce) phosphor powder synthesis with a nanocrystalline structure was developed.Nanocrystalline YAG:Ln powder was prepared by an ultrasonic atomization and co-precipitation method using a mixture solution of ammonium hydroxide(NH3·H2O) and ammonium hydrogen carbonate(NH4HCO3) as precipitant.The as-prepared nano-powders were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),and fluorescence spectrometer.The obtained phosphor powders were homogenous and in size of 50-70 nm.The results demonstrated that by using ultrasonic atomization and co-precipitation process,we could synthesize a good quality YAG:Ln(Ln=Eu,Ce) phosphor powder that had many potential applications.  相似文献   

12.
Two 1D coordination polymers [Ln2(dpdc)3(tpy)2·H2O]n [Ln=Nd 1, Yb 2, H2dpdc=2,2’-biphenyldicarboxylic acid and tpy= 2,2’:6’,2’’-terpyridine] and one dinuclear complex Er2(dpdc)2(Hdpdc)2(tpy)2 3 were obtained via hydrothermal reactions and determined by X-ray diffraction analysis. The crystal structure data of 1 and 2 revealed that two coordination polymers were isostructural and possessed a 1D chain framework consisting of eight-coordinated Ln(III) centers. In the asymmetric unit, the two Er(III) ions in 3 were both nine-coordinated and had similar coordination environments. The Er(III) ions were bridged by dpdc2-ligands into dinuclear structures. The complexes were also characterized by IR spectra and thermogravimetric analysis. The solid fluorescence of 1 and 3 was also investigated at room temperature.  相似文献   

13.
PreparationandCharacterizationofHeteropolytungstoarsenateComplexesContainingLanthanideElements¥WangWeiqing(DepartmentofChemic...  相似文献   

14.
A novel pyrazolone pyridine-containing ligand,2,6-bis(1-phenyl-4-ethoxycarbonyl-5-pyrazolone-3-yl)pyridine (H2L) was de-signed and synthesized from pyridine-2,6-dicarboxylic acid (1),and its Eu(III) and Tb(III) complexes were prepared.The ligand and com-plexes were characterized in detail based on FT-IR spectra,1H NMR,elemental analysis and thermal analysis,and the formula of Ln2L3·4H2O (Ln=Eu or Tb) of rare earth complexes was confirmed.The UV-vis absorption spectra and photoluminescence properties of the complexes were investigated,which showed that the Eu(III) and Tb(III) ions could be sensitized efficiently by the ligand (H2L) and emit the photolumi-nescence with high intensity,narrow half-peak width,and monochromic light.The results indicated that the complexes showed potential as excellent luminescent materials.  相似文献   

15.
1 ,10 Phenanthrolinehasbeenextensivelyusedasanazaheterocyclicchelateligandinbothanalyticalandpreparativecoordinationchemistry[1] .Asanim portantligand ,1,10 phenanthrolineunitplaysanim portantroleforthedevelopmentofthesupramolecularchemistry .Manynovelsupramolecularcompoundsin clude 1,10 phenanthrolineunit[2~ 4 ] .Furthermore ,consideringtheuniquecombinationofchemicalstabil ities ,redoxproperties ,luminescenceemissionandex citedstatelifetime ,derivativesof 1,10 phenanthrolinehaveplayedama…  相似文献   

16.
A Schiff base L [2-thiophenecarboxylic acid, 2-(2-pyridinylmethylene)hydrazide] with its lanthanide metal complexes was synthesized. These complexes were characterized by elemental analysis, molar conductivity measurements, spectral analysis(NMR, FT-IR, and UV-Vis), luminescence and thermal gravimetric analysis. The Schiff base ligand was a tridentate chelate and coordinates to the central lanthanide ion with 1:2 metal:ligand ratio. The conductivity data showed a 1:1 electrolytic nature with a general formula [LnL_2(NO_3)_2]NO_3. The luminescence emission properties for Sm, Tb, and Eu complexes were observed and showed that the ligand L could absorb and transfer energy to Sm(III), Tb(III) and Eu(III) ions. The complexes possessed a good antibacterial activity against different bacterial strains. In addition, the scavenging activity of the Ln(III) complexes on DPPH was concentration dependant and the complexes were significantly more efficient in quenching DPPH than the free Schiff base ligand.  相似文献   

17.
Deep eutectic solvents(DESs) were used for luminescence measurements in quantitative analysis of trivalent lanthanide ions and as solvents for light rare earth elements(LREE) in solid-liquid separation.The spectroscopic characteristics of lanthanide chlorides LnCl_3(Ln=Eu,Tb),respectively their aquo complexes,are described in a comprehensive study that demonstrates the significant enhancement of the phosphorescence emission intensity in DESs as polar and weakly coordinating solvent.Several DESs stabilize the lanthanide ion luminescence against changes in temperature and moisture,which is advantageous compared with the use of ionic liquids.Small amounts of water lead in certain eutectic systems even to a further increase in phosphorescence emission intensity.By investigating the solubility of lanthanide sesquioxides Ln_2 O_3(Ln=La,Nd,Sm,Eu,Gd,Tb,Dy) in DESs,selectivities are identified that may be of use for the separation of LREE.  相似文献   

18.
Coordination chemistry of rare earth with Schiffbase has developed rapidly in the last fewyears ,butthe majority of the complexes studied are derivedfromaromatic Schiff base .So far less papers of rare earthcomplex with aliphatic Schiff base have been rep…  相似文献   

19.
Thepreparationofanhydrousrareearthhalidescanbetracedbacktothebeginningofthe20thcentury[1].Thepreparationmethodsmaybeclassifiedasthreetypes,halogenationofmetals,halogenationofrareearthoxides,anddehydrationofrareearthhalidehydrates[2].Thereactionsbetweenrare…  相似文献   

20.
The novel phosphors of La 2 MoO 6 activated with the trivalent rare earth Ln 3+ (Ln=Eu, Sm, Dy, Pr, Tb) ions were synthesized by solid state reactions at high temperature in air atmosphere, and their phase impurities and luminescent properties were studied. The photoluminescence (PL) excitation and emission spectra, and decay curves were employed to study their luminescence properties. The lifetimes of the characteristic emissions from Ln 3+ ions were in the order of millisecond except Pr 3+ ions. (LaEu 1-x ) 2 MoO 6 was a promising phosphor for practical application and the optimum concentration was x=0.075. The concentration quenching mechanism of Eu 3+ was also discussed by theoretical fitting using Burshtein model.  相似文献   

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