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1.
合成并通过单晶衍射表征了3个稀土配合物Ln(L)(NO3)3(H2O)(L=N-苯基-2-(5-氯-8-喹啉氧基)乙酰胺,Ln=Eu (1),Gd (2),Er (3)),结构与拥有相同有机配体的Pr,Nd和Sm配合物同构。在每个配合物中,十配位的稀土离子采取扭曲的双帽四方反棱柱配位构型,分别与来自1个配体L的2个氧原子和1个氮原子,2个双齿配位硝酸根和1个水分子配位。配合物1能够发射Eu(Ⅲ)离子特征荧光,荧光寿命为437 μs。  相似文献   

2.
合成并通过单晶衍射表征了3个稀土配合物[LaL2(NO3)3]·CH3CN(1),[Ln(L)(NO3)3(H2O)](Ln=Tb (2), Dy (3), L=N-苯基-2-(5-氯-8-喹啉氧基)乙酰胺)。在配合物1中,十二配位的La(Ⅲ)离子采取扭曲的二十面体配位构型,分别与来自2个酰胺配体L的4个氧原子和2个氮原子,及3个双齿配位硝酸根配位。配合物23的结构与拥有相同有机配体的Pr、Nd、Sm、Eu、Gd和Er配合物同构。在每个配合物中,十配位的稀土离子与来自1个配体L的2个氧原子和1个氮原子,3个双齿配位硝酸根和1个水分子配位,拥有扭曲的双帽四方反棱柱配位构型。固态配合物23在可见区发射强荧光。  相似文献   

3.
合成并通过单晶衍射表征了3个稀土配合物[LaL2(NO3)3]·CH3CN(1),[Ln(L)(NO3)3(H2O)](Ln=Tb(2),Dy(3),L=N-苯基-2-(5-氯-8-喹啉氧基)乙酰胺)。在配合物1中,十二配位的La(Ⅲ)离子采取扭曲的二十面体配位构型,分别与来自2个酰胺配体L的4个氧原子和2个氮原子,及3个双齿配位硝酸根配位。配合物23的结构与拥有相同有机配体的Pr、Nd、Sm、Eu、Gd和Er配合物同构。在每个配合物中,十配位的稀土离子与来自1个配体L的2个氧原子和1个氮原子,3个双齿配位硝酸根和1个水分子配位,拥有扭曲的双帽四方反棱柱配位构型。固态配合物23在可见区发射强荧光。  相似文献   

4.
合成并通过单晶衍射表征了3个同构稀土配合物Ln(L)(NO3)3(H2O)(L=N-苯基-2-(5-氯-8-喹啉氧基)乙酰胺,Ln=Pr(Ⅲ),l;Nd(Ⅲ),2;Sm(Ⅲ),3)。在每个配合物中,十配位的稀土离子采取扭曲的双帽四方反棱柱配位构型,分别与来自1个配L的2个氧原子和1个氮原子,2个双齿配位硝酸根和1个水分子配位。配合物3能够发射Sm(Ⅲ)离子征荧光,荧光寿命为11.7μs。  相似文献   

5.
合成并通过单晶衍射表征了3个稀土配合物Ln(L)(NO3)3(H2O)(L=N-苯基-2-(5-氯-8-喹啉氧基)乙酰胺,Ln=Eu(1),Gd(2),Er(3)),结构与拥有相同有机配体的Pr,Nd和Sm配合物同构。在每个配合物中,十配位的稀土离子采取扭曲的双帽四方反棱柱配位构型,分别与来自1个配体L的2个氧原子和1个氮原子,3个双齿配位硝酸根和1个水分子配位。配合物1能够发射Eu(Ⅲ)离子特征荧光,荧光寿命为437μs。  相似文献   

6.
制备了以3-((4,6-二甲基-2-嘧啶基)硫代)-丙酸(HL)和菲咯啉(Phen)为配体的2个三元稀土配合物[Eu(L)3(Phen)]2·2H2O(1)和[Tb(L)3(Phen)]2·2H2O(2),并对其结构进行了表征。单晶X射线衍射分析表明它们是同构的。2个稀土离子(Ln)由4个羧酸配体桥接,形成二聚体排列。其余2个羧酸配体和Phen以双齿螯合方式与Ln配位。Ln的配位数为9,具有扭曲的单端方形反棱柱配位多面体构型。固态光致发光测试表明,这2种配合物都显示了金属中心的特征发射带。  相似文献   

7.
通过配体1,3-苯二胺缩邻香兰素和Ln(acac)3·H2O(Ln=Ce,Eu)反应,合成了2个双核稀土配合物[Ce2L(acac)4(CH3OH)]2·2CH3Cl21)和[Eu2L(acac)4(CH3OH)]2·2CH2Cl22)。X射线单晶衍射分析确定了配合物的晶体结构,配合物中2个稀土离子均为8配位,具有相同的反四棱柱的配位构型。荧光性质研究表明配合物2显示稀土离子和配体共发光,主要原因是配体1,3-苯二胺缩邻香兰素的三线态能级与中心离子Eu(Ⅲ)的三线态能级相匹配。  相似文献   

8.
合成并通过单晶衍射表征了配合物[Cd(L)(H2O)(NO3)2] (1)和[Cd(L)I2]·CH3OH (2)(L=喹啉-8-甲醛对羟基苯甲酰腙)。单晶衍射结果表明,在配合物1中,Cd(Ⅱ)分别与1个三齿配位的酰腙配体,1个水分子,1个单齿配位和1个双齿配位的硝酸根配位,从而拥有单帽三棱柱配位构型。然而,配合物2中,Cd(Ⅱ)离子采取扭曲的四方锥配位构型,与来自配体L的N2O电子供体以及2个碘离子配位。此外还详细研究了配合物12的热稳定性及荧光性质。  相似文献   

9.
合成并通过单晶衍射表征了配合物[Cd(L)(H2O)(NO3)2](1)和[Cd(L)I2]·CH3OH(2)(L=喹啉-8-甲醛对羟基苯甲酰腙)。单晶衍射结果表明,在配合物1中,Cd(Ⅱ)分别与1个三齿配位的酰腙配体,1个水分子,1个单齿配位和1个双齿配位的硝酸根配位,从而拥有单帽三棱柱配位构型。然而,配合物2中,Cd(Ⅱ)离子采取扭曲的四方锥配位构型,与来自配体L的N2O电子供体以及2个碘离子配位。此外还详细研究了配合物12的热稳定性及荧光性质。  相似文献   

10.
合成并通过单晶衍射表征了一个配合物[CdL(H2O)(NO3)]NO3·CH3COCH3 (1)(L=N-甲基N-苯基-2-(8-喹啉氧基)乙酰胺)。在配合物1中,金属镉离子采取扭曲的八面体配位构型。来自配体L的1个氧原子和2个氮原子,2个硝酸根的2个氧原子及配位水分子的1个氧原子与中心镉离子配位。配合物通过分子间的O-H…O氢键作用构筑成沿a轴的一维链状结构。乙腈溶液中配体L和配合物1均在390 nm有荧光发射,但配合物的荧光强度要远低于配体。  相似文献   

11.
The direct reaction of europium with 2-propanol and phenols has been investigated under a variety of conditions. The reaction of europium metal with 2,6-dimethylphenol and 2,6-diisopropylphenol in 2-propanol at reflux revealed that polymetallic europium complexes could be generated by this method. Hx[Eu8O6(OC6H3Me2-2,6)12(OiPr)8], 1, and H5[Eu5O5(OC6H3iPr2-2,6)6(NCCH3)8], 2, were isolated by recrystallization in the presence of hexanes and acetonitrile, respectively, and characterized by X-ray crystallography. Complex 1 has a cubic arrangement of europium ions with face-bridging mu 4-O donor atoms, edge-bridging mu-O(phenoxide/phenol) ligands, and terminal O(isopropoxide/2-propanol) ligands. Complex 2 is mixed valent and has a square pyramidal europium core with four Eu(II) ions at the basal positions and one Eu(III) ion at the apex. Since these reactions gave complicated mixtures of products from which 1 and 2 could only be obtained in low yields, direct reactions under less forcing reaction conditions were investigated. Europium reacts slowly at room temperature to form arene-soluble divalent [Eu(OiPr)2(THF)x]n, 3. Complex 3 reacts with 2,6-dimethylphenol to form the arene-insoluble complex (H[Eu(OC6H3Me2)2(OiPr)])n, 4. Recrystallization of 4 in the presence of THF results in the crystallographically characterizable divalent trimetallic complex [Eu(OC6H3Me2-2,6)2(THF)2]3, 5, which has an unusual linear metal geometry. In the presence of HOiPr at ambient conditions in the glovebox, crystals of 5 slowly convert to the mixed valent H10[Eu8O8(OC6H3Me2-2,6)10(OiPr)2(THF)6], 6, which was found to have a cubic arrangement of europium atoms similar to 1 by X-ray crystallography. Complex 4, upon heating under vacuum, followed by reaction with THF, forms the arene-soluble divalent complex H18([Eu9O8(OC6H3Me2-2,6)10(THF)7][Eu9O9(OC6H3Me2-2,6)10(THF)6]), 7, which contains two types of capped cubic arrangements of europium ions in the solid state.  相似文献   

12.
研究了BaLiF3中Gd3+和Eu2+的光谱性质及Gd3+对Eu2+的能量传递过程,讨论了传递机理.Gd3+的含量(物质的量分数)为0.3%时,传递效率最高,传递几率PSA=1.35×105 s-1.当Gd3+的含量高于0.3%时,由于Gd3+和Eu2+竞争吸收Gd3+占优势,增加Gd3+含量,竞争吸收比相应增加,Eu2+自身吸收光子数目减少,发射强度降低.  相似文献   

13.
Investigations on the Chemical Transport of the Anhydrous Europium Chlorides EuCl2, Eu5Cl11, Eu4Cl9, Eu14Cl33 and EuCl3 with AlCl3 . Aluminium trichloride is known as a versatile transporting agent for rare-earth trichlorides, but in case of europium the dichloride EuCl2 as well as the mixed-valence compounds Eu5Cl11, Eu4Cl9 and Eu14Cl33 can be chemically transported, too. The observed transport directions are discussed in terms of partial-pressure and solubility diagrams. Under appropriate conditions the gas-phase complex Eu(AlCl4)2 is obtained as a crystalline solid. Being isostructural with Sr(AlCl4)2, the crystal structure of which has been determined very recently, Eu(AlCl4)2 is the first chloroaluminate of a rare-earth element in the divalent state.  相似文献   

14.
15.
杂质的添加对SrAl2O:Eu^2+,Dy^3+余辉发光特性的改善   总被引:16,自引:5,他引:11  
采用溶胶-凝胶法制备SrAl2O4:Eu^2 ,Dy^3 磷光体,并在合成过程中添加硼或硅以探讨光致发光及长余辉发光性质。发现硼、硅添加物不仅是助熔剂,且能改良SrAl2O4:Eu^2 ,Dy^3 之长余辉的持续时间及余辉发光强度。基于不同磷光体样品的实验结果比较,综合材料表面微结构观察、X射线衍射图谱、热释发光光谱与余辉衰减曲线的测量等实验结果分析,推断在SrAl2O4:Eu^2 ,Dy^3 中添加硼、硅可导致磷光体缺陷增加并稳定活化剂Eu^2 的价态。  相似文献   

16.
Intercalation of C(70) with europium affords two kinds of magnetic compounds, a canted antiferromagnet Eu(x)C(70) (x approximately 3) and a ferromagnet Eu(x)C(70) (x approximately 9) with transition temperatures (T(C)) of 5 and 38 K, respectively. The Curie constants in the paramagnetic phase and the saturation moment in the ferromagnetic phase are both understood by the full moment of Eu(2+) for both systems. The structure of Eu(3)(-)(delta)C(70) (delta approximately 0.27) is pseudo-monoclinic, derived by a simple deformation of the parent face-centered cubic (fcc) structure. Eu(9)(-)(delta)C(70) (delta approximately 0.2) forms an fcc structure, in which cuboctahedral clustering of Eu(2+) ions is observed in the enhanced size octahedral holes. The observed T(C) of the Eu(9)(-)(delta)C(70) ferromagnet is comparable to or larger than those of simple binary Eu-based ferromagnets, such as Eu chalcogenides or carbides, despite the low atomic ratio of Eu in the chemical formulas. This can be understood by the short Eu(2+)-Eu(2+) distances and high coordination numbers permitted by the multiple occupation by Eu(2+) ions of the expanded octahedral interstitial sites in higher fullerene-based solids.  相似文献   

17.
Nanocrystals of oxides containing europium as the main constituent or as a doping element in RE2O3 ( RE=Y, Gd) have been prepared by direct oxide precipitation in high-boiling polyalcohol solutions and characterized by high-resolution TEM, absorption spectroscopy, and luminescence spectroscopy. The samples obtained consisted of concentrated and colloidally stable suspensions of luminescent oxide nanoparticles with an average grain diameter in the range 2-5 nm. The nanoparticles were found to be highly crystalline despite their ultrasmall size and the low temperature of 180 degrees C applied during the synthesis. Upon UV excitation, the red luminescence relative to the 5D0-->7Fn transition within the cubic form of RE2O3 exhibits some important differences from that usually found in bulk materials.  相似文献   

18.
EuPtP, Eu1–xGdxPtP, and Eu0.5Sr0.5PtP: Structures and Intermediate Valence EuPtP with a strong temperature dependence of the Eu-valency undergoes two first order phase transitions at 235 K (α-/β-form) and 190 K (β-/γ-form). The compound crystallizes in a modified Ni2In-type structure, the P-atoms (α-, β-EuPtP) and the Pt-atoms too (γ-EuPtP) are shifted towards one of two Eu-layers. Compounds of the series Eu1–xGdxPtP and Eu0.5Sr0.5PtP crystallize in the same type of structure as α- or β-EuPtP, but don't undergo with x > 0.05 the above mentioned phase transitions. They were studied by LIII—X-ray absorption and susceptibility measurements: The valence of Eu shows roughly the same temperature dependence as in EuPtP, only one magnetic order transition was found. The structural details and the behaviour of these compounds are discussed with a domain picture.  相似文献   

19.
用高温固相反应法合成了铌酸根NbO^3-4和Eu^3 共掺杂的正钽酸盐化合物Y1-xEuxTa1-yNbyO4,研究该体系中紫外光和X射线激发下的发光性能,研究表明,在紫外光激发下,YTaO4:Nb,Eu是一种比较有效的红色发光材料,激发能可以通过NbO^3 4离子传递给Eu^3 ,随钽酸盐中NbO^3-4基团浓度的增中,化合物的结构从M'型YTaO4变成褐钇铌型YNbO4结构,它的发光性质也随之改变。  相似文献   

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