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1.
本文采用密度泛函理论中的M05方法对比研究了一类双席夫碱及其衍生物与金属Co、Ni和Cu配位后配合物的结构,非线性光学性质以及激发态性质.结果表明,Co配合物的三重态,Ni配合物的二重态以及Cu配合物的单重态为最佳稳定结构.通过最佳稳定结构计算得到的配合物非线性光学性质表明,三种金属配合物中Cu配合物表现出较高的一阶和二阶超极化率.通过对其激发态性质分析表明在配体苯环上引入甲氧基使电子跃迁种类减少,导致超极化率下降,非线性光学性质减弱.  相似文献   

2.
本文采用密度泛函理论中的M05方法对比研究了一类双席夫碱及其衍生物与金属Co、Ni和Cu配位后配合物的结构,非线性光学性质以及激发态性质. 结果表明,Co配合物的三重态,Ni配合物的二重态以及Cu配合物的单重态为最佳稳定结构. 通过最佳稳定结构计算得到的配合物非线性光学性质表明,三种金属配合物中Cu配合物表现出较高的一阶和二阶超极化率. 通过对其激发态性质分析表明在配体苯环上引入甲氧基使电子跃迁种类减少,导致超极化率下降,非线性光学性质减弱.  相似文献   

3.
铒有机配合物的合成、表征与近红外发光性能研究   总被引:1,自引:1,他引:0  
合成了乙酰基丙酮(AcAc)和二苯甲酰基甲烷(DBM)的水合二元铒配合物以及乙酰基丙酮、二苯甲酰基甲烷和三氟乙酰基丙酮(TFA)分别与1,10-邻菲罗啉(Phen)的三元铒配合物,并经元素分析确认;表征了配合物的紫外-可见吸收光谱和红外吸收光谱;探讨了铒配合物的近红外发光性能,并对不同配体对发光性能的影响进行分析比较。结果表明Er(AcAc)3Phen三元配合物是所研究的几种配合物中近红外发光性能最优的。  相似文献   

4.
合成了四种含硫氨基葡萄糖金属配合物(M-GLUS,M=Co, Cu, Ni和Zn),利用元素分析,摩尔电导,核磁共振氢谱进行了结构表征。结果表明含硫配体与这四种二价金属离子均形成了2∶1型非电解质配合物。在pH 7.08 Tris缓冲液中,采用紫外吸收光谱和荧光光谱研究了金属配合物与小牛胸腺DNA的作用机制,发现随着金属配合物量的逐渐增加,DNA电子吸收光谱的最大吸收峰呈增色效应,对配合物DNA-EB体系也能产生荧光猝灭作用,说明四种金属配合物均可与DNA发生相互作用,结合方式为部分插入;在近似生理酸度条件下,利用荧光光谱对金属配合物与HSA/BSA的结合特性进行了初步分析,发现配合物均能猝灭HSA/BSA的荧光强度,利用Scatchard方程计算了四种金属配合物与HSA/BSA的结合常数和结合位点数,表明金属配合物与血清白蛋白有较强的结合且只有1类键合位,其中Co-GLUS与蛋白的结合力最强。  相似文献   

5.
合成了稀土Tb-N-苯基邻氨基苯甲酸-1,10-菲咯啉二元、三元配合物。通过元素分析确定二元配合物的组成为TbL3·4H2O,三元配合物的组成为TbL3phen·2H2O(L: N-苯基邻氨基苯甲酸根,phen: 1,10-菲咯啉),讨论了两种配合物的谱学性质。通过荧光光谱测试发现,形成的TbL3·4H2O二元配合物的荧光强度明显降低,1,10-菲咯啉作为第二配体引入后,使Tb3+的发光强度继续降低,这说明了Tb3+的发光强度与配体的结构有关,通过结构、能量传递和能量匹配对此做了进一步的解释。  相似文献   

6.
本文合成了三种稀土与对硝基苯乙酸 (HL)的二元固体配合物 ,通过元素分析等手段确定了其配合物的组成为ReL3·H2 O(Re=Eu ,Sm ,Tb)。用红外光谱、紫外光谱、荧光光谱对该类配合物的结构与性质进行了表征。红外谱表明配体以—COO- 形式与中心离子配位 ,同时这一点也被自由配体和配合物的UV谱所证实。EuL3·H2 O的强红色荧光分属于Eu3+ 的 5D0 → 7F1 和5D0 → 7F2 跃迁。  相似文献   

7.
铽与苯甲酸及其衍生物配合物的合成与发光特性   总被引:3,自引:0,他引:3       下载免费PDF全文
合成了铽与苯甲酸及其衍生物(苯甲酸、邻苯二甲酸、间苯二甲酸、水杨酸、邻氨基苯甲酸、磺基水杨酸)的配合物。经元素分析确定其组成结构式。研究了它们的红外吸收光谱、紫外吸收光谱及荧光光谱。紫外光谱的研究表明,配合物的紫外吸收主要表现为配体的吸收;红外光谱的研究表明,配合物的红外光谱不同于自由配体的红外光谱;荧光光谱的研究表明,铽与这六个配体的配合物都表现出较好的荧光性能,并发现磺基水杨酸铽配合物在本实验系列中其荧光发射最强。  相似文献   

8.
Halide ion conductivities of the complexes of cryptand[2.2.2] with alkali-metal halides or alkaline-earth metal halides were measured at 20–160°C. The halide ion conductivities of the complexes were found to be much higher than those of the crown ether complexes with alkali-metal halides or alkaline-earth metal halides. This is caused by the much weaker Coulomb attraction between metal-cation and halide ion in cryptand complexes than in crown ether complexes.  相似文献   

9.
The experimental fourier transform infrared (FT-IR) and ultraviolet-visible (UV-Vis) spectra of copper(II) and nickel(II) complexes of the deprotonated tetradentate Schiff base ligand N,N′-bis(2-hydroxybenzylidene)-2,2-dimethyl-1,3-propanediamine (H2L) are compared with their corresponding theoretical ones. The applied theoretical method is based on the density functional theory and time-dependent density functional theory at the UPBE0/PBE0 levels using Def2-TZVP basis set. The computational optimised geometric parameters of the complexes are in good agreement with their corresponding experimental data. The FT-IR and UV-Vis spectra of the complexes were reproduced on the basis of their optimised structures. The vibrational assignments of some fundamental modes of the complexes are performed. The highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energies are calculated. The analyses of the calculated electronic absorption spectra of the complexes are carried out to elucidate the electronic transitions assignments and their characters. Second-order nonlinear optical property of the complexes is evaluated by the above-mentioned theoretical method that implies much greater values for the complexes in comparison with the corresponding value of urea.  相似文献   

10.
The hydrogen bonded complexes between hydroxylic derivatives and carbonyl bases have been extensively studied by infrared spectroscopy but meager Raman spectroscopic results are available for such complexes. This work reports on a study of the Raman intensity of the vC[dbnd]0 stretching vibration of hydrogen bonded complexes formed between acetophenone and some phenol derivatives. The formation constants of these complexes are calculated from infrared spectroscopy.  相似文献   

11.
We report on the results of ab initio calculations of vacancy and hydrogen-vacancy complexes in palladium and palladium hydride. Comparative analysis of the energies of the formation of defect complexes in palladium and its hydride has revealed that the formation of vacancy clusters is easier in the palladium hydride structure. Investigation of hydrogen-vacancy complexes in bulk crystalline palladium has shown that a hydrogen atom and a vacancy interact to form a stable hydrogen-vacancy (H-Vac) defect complex with a binding energy of E b = ?0.21 eV. To investigate the initial stage in the formation of hydrogen-vacancy complexes (H n -Vac m ), we consider the clusterization of defects into clusters containing H-Vac and H2-Vac complexes as a structural unit. It is found that hydrogen-vacancy complexes form 2D defect structures in palladium in the (100)-type planes.  相似文献   

12.
铽-芳香化合物-丁二酸发光配合物的合成及性能   总被引:1,自引:1,他引:0       下载免费PDF全文
以苯甲酸及其衍生物为第一配体、丁二酸为第二配体,在非水性溶剂条件下合成了6种新的铽三元荧光配合物。利用元素分析、EDTA配位滴定分析、红外光谱和紫外吸收光谱分析对目标物的组成与结构进行了表征,并研究了其发光性能和热稳定性。结果表明:丁二酸的引入显著地加强了各第一配体向中心铽离子传递能量的能力,其传递能量的顺序为:对氯苯甲酸>间氯苯甲酸>大茴香酸>对甲基苯甲酸>苯甲酸>对羟基苯甲酸。目标配合物与其相对应的二元配合物比较荧光强度有了显著的提高。  相似文献   

13.
A theoretical study of the complexes formed between dimethyl sulfoxide (DMSO) and hypohalous acid (HOX, X = Cl, Br, and I) has been carried out at the MP2/aug-cc-pVTZ level. For each HOX, four minima binary complexes were found, two mainly with an OH???O hydrogen bond and the other two with an OX???O halogen bond. The hydrogen-bonded complexes are more stable than the halogen-bonded analogues for HOCl and HOBr, while both types of complexes have similar stability in the iodine case. A red shift was found for the associated H–O and X–O bond stretch vibrations and a small blue shift for the distant bonds. As the oxygen of DMSO simultaneously binds with two HOCl molecules, the corresponding interactions are weakened with diminutive effect. This diminutive effect is the largest in the complexes with two OH???O hydrogen bonds but the smallest in those with two OCl???O halogen bonds.  相似文献   

14.
合成了4种新的糖胺 金属配合物,分别为[Ni(HL) (H2 O) 2 ]2 Cl2 ·CH3OH·2H2 O ,[Cu(HL) ]2 Cl2 ·CH3CH2 OH·3H2 O ,[Zn(HL) ]2 Cl2 ·H2 O ,[Co(HL) (H2 O) (OH) ]2 Cl2 ·CH3OH·2H2 O (HLN ,N′ 二βD 葡萄糖基乙二胺) ,并用元素分析、红外、紫外、核磁共振氢谱对其结构进行了表征。结果表明,Ni(Ⅱ) ,Co(Ⅲ)配合物为八面体构型,而Cu(Ⅱ) ,Zn(Ⅱ)配合物为四面体构型。最后研究了其对对硝基苯吡啶甲酸酯(PNPP)催化水解的催化速率常数。  相似文献   

15.
铕镧苯甲酸α,α′-联吡啶配合物的合成及性质研究   总被引:11,自引:2,他引:9  
在乙醇介质中合成了以Eu3+ 和La3+ 为中心体、苯甲酸和α ,α′ 联吡啶为配体的混合稀土配合物。测定了配合物的组成、研究了其紫外光谱和红外光谱。结果表明 ,配合物的组成为EuxLa1 -x(Dipy)L3·H2 O ,苯甲酸和α ,α′ 联吡啶的紫外吸收峰在配合物中分别位移了 2~ 9nm ;苯甲酸根羧基的反对称伸缩振动和对称伸缩振动在配合物中向低波数移动 ,而α ,α′ 联吡啶的CN振动则向高波数移动。这些事实表明 ,苯甲酸和α ,α′ 联吡啶与稀土离子配位。荧光测试表明 ,用不发光的镧离子取代该系列配合物中部分铕离子 ,在一定范围内 ,可以提高三价铕的特征荧光发射强度。这一结果也表明 ,在该系列配合物中 ,不仅配体可以将吸收的能量传递给发光的铕离子 ,使其发光 ,而且不发光的镧配合物也可将其吸收的能量通过分子内能量传递给铕离子 ,增强铕的发光强度。  相似文献   

16.
以苯氧乙酸和邻菲啰啉为配体,不同比例铽钇为中心,在无水乙醇中合成了一系列铽掺钇配合物?素分析和稀土络合滴定推测配合物的组成为TbxY1-x(POA)3phen·1/2H2O(POA-=C6H5OCH2COO-,x=1.0,0.9,0.8,0.7,0.6,0.5,0.4,0.3,0.2,0.1)。红外光谱测试表明,苯氧乙酸的羧基氧及苯氧基氧与稀土离子配位。邻菲啰啉的两个氮原子也与稀土离子配位;热分析表明:该系列配合物在274℃附近失去配位水,温度高于576℃发生氧化分解。荧光光谱测试结果表明:该系列配合物都可发出较强的特征荧光,在一定比例范围内,钇可以增强铽的发光,组成为配合物Tb0.7Y0.3(POA)3phen·1/2H2O荧光最强;荧光寿命与荧光强度变化一致。  相似文献   

17.
以对苯二甲酸(p-PA)、苯甲酸(BA)、邻(间、对)甲基苯甲酸[o(m、p)-MBA]和1,10-邻菲啰啉(phen)为配体,合成了4种Eu(Ⅲ)和4种Tb(Ⅲ)的四元配合物。通过EDTA配位滴定分析和元素分析,确定了各配合物的组成。利用红外光谱分析对配合物的结构进行了初步表征,在配合物中羧基氧原子和1,10-邻菲啰啉中的氮原子均参与了配位。在室温条件下,测定了各固体配合物的激发和发射光谱,结果表明:4种铕的四元配合物中,苯甲酸配合物在614 nm最强发射峰的荧光强度强于3种甲基取代苯甲酸配合物的荧光强度;4种铽的四元配合物中,以对甲基苯甲酸为配体的配合物在545 nm最佳发射峰和490 nm次强发射峰的荧光强度较高。  相似文献   

18.
Several functionalized β-diketones and their europium complexes have been synthesized and characterized. The UV-Vis absorption, photoluminescent spectra, thermal and electrochemical properties of these complexes were investigated. The thermal analysis shows that the complexes have good thermal stability. By introducing the number of extended phenyl rings we succeeded in obtaining europium complexes with extremely high photoluminescent quantum yield (PLQY) in solution due to strong site isolation effect.  相似文献   

19.
Experiment 1 measured frequency modulation detection thresholds (FMTs) for harmonic complex tones as a function of modulation rate. Six complexes were used, with fundamental frequencies (F0s) of either 88 or 250 Hz, bandpass filtered into a LOW (125-625 Hz), MID (1375-1875 Hz) or HIGH (3900-5400 Hz) frequency region. The FMTs were about an order of magnitude greater for the three complexes whose harmonics were unresolved by the peripheral auditory system (F0 = 88 Hz in the MID region and both F0s in the HIGH region) than for the other three complexes, which contained some resolved harmonics. Thresholds increased with increases in FM rate above 2 Hz for all conditions. The increase was larger when the F0 was 88 Hz than when it was 250 Hz, and was also larger in the LOW than in the MID and HIGH regions. Experiment 2 measured thresholds for detecting mistuning produced by modulating the F0s of two simultaneously presented complexes out of phase by 180 degrees. The size of the resulting mistuning oscillates at a rate equal to the rate of FM applied to the two carriers. At low FM rates, thresholds were lowest when the harmonics were either resolved for both complexes or unresolved for both complexes, and highest when resolvability differed across complexes. For pairs of complexes with resolved harmonics, mistuning thresholds increased dramatically as the FM rate was increased above 2-5 Hz, in a way which could not be accounted for by the effect of modulation rate on the FMTs for the individual complexes. A third experiment, in which listeners detected constant ("static") mistuning between pairs of frequency-modulated complexes, provided evidence that this deterioration was due the harmonics in one of the two "resolved" complexes becoming unresolved at high FM rates, when analyzed over some finite time window. It is concluded that the detection of time-varying mistuning between groups of harmonics is limited by factors that are not apparent in FM detection data.  相似文献   

20.
The Pd(II) and Pt(II) complexes with two dibasic tridentate ligands viz. o-vanillin thiosemicarbazone and o-vanillin-4-phenylthiosemicarbazone, have been synthesized and characterized on the basis of their elemental analysis, magnetic susceptibility, conductance, ir and electronic spectral and thermogravimetric data. The presence of chlorine atom in the coordination sphere imparts a square planar geometry to these complexes having the general formula [M (L) Cl]. The mixed ligand complexes of the type [M (L) py. H2O] have also been prepared employing pyridine as an additional heterocyclic base. The complexes are square pyramidal and the presence of chlorine, water molecules is revealed by the study of their thermograms supported by the presence of relevant bands in their ir spectra. Suitable structures have been assigned to these binary and ternary complexes.  相似文献   

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