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1.
在一定的溶液条件下,卟啉分子经自组装而形成卟啉聚集体。通过改变卟啉浓度和改变溶液环境两个途径诱导四-[3-甲氧基-4-(N-咔唑)正丁氧苯基]卟啉(4C4-TPP)聚集,利用吸收光谱,荧光光谱,对聚集前后的结构进行表征。从紫外-可见光谱和荧光光谱的结果看出,浓度小于3.34×10~(-6)M时,4C4-TPP不仅分子内、分子间没有发生共轭作用,而且分子的对称性和平面性也都没有变化,4C4-TPP以单体形式存在的,当浓度大于3.34×10~(-6)M后分子构型发生变化。变化有可能来自于分子内,也可能来自于分子间。  相似文献   

2.
制备了β-萘甲酸十六碳酯的L-B膜。分别用Y型、Z型,以及含有硬脂酸的β-萘甲酸十六碳酯与单纯硬脂酸间隔挂法,将分子膜转移至石英载片上,研究了β-萘甲酸十六碳酯分子膜吸收以及荧光光谱。并与溶液和固态中的荧光光谱作了比较。在氯仿溶液以及在固态,β-萘甲酸十六碳酯只呈现其单体的荧光。然而,在L-B膜中,除了观察到单体的荧光外,还观察到了激发态二聚体以及激基缔合物发射的荧光。通过对β-萘甲酸十六碳酯分子膜进行热和水处理后,发现L-B膜中亲水层的介质环境有所改变,从而造成亲水层中的亲水基团的某些物理和化学性质的改变。根据实验事实,提出了β-萘甲酸十六碳酯二聚体和激基缔合物在L-B膜中形成的机制。  相似文献   

3.
通过5,10,15,20-四[3,5-二(羟基)苯基]卟啉与癸酰氯反应,合成出5,10,15,20-四[3,5-二(癸酰氧基)苯基]卟啉,并通过金属化得到该卟啉的锌、铜配合物。通过紫外-可见吸收光谱,红外光谱,核磁共振氢谱等对产物进行了表征,并且研究了卟啉的液晶性质和荧光性质。  相似文献   

4.
以2,4-二氯-6-辛氧基-1,3,5-三嗪为原料,经Kumada偶联及胺化两步反应合成了三嗪胺衍生物:4-(9-蒽基)-6-辛氧基-1,3,5-三嗪-2-胺(AOOTA),总产率为38%.通过紫外-可见吸收光谱及荧光光谱研究了氯仿溶液中AOOTA在乙酸(HOAc)及三氟乙酸(TFA)作用下的光谱行为.研究发现AOOTA与HOAc在基态及激发态下均不能发生双氢键作用,而AOOTA与TFA相互作用基态下形成双氢键复合物,激发态下由于分子中蒽基及辛氧基与三嗪环间的C—C单键以及C—O单键的自由旋转,从而使得AOOTA与TFA分子间不能形成有效的氢键相互作用.  相似文献   

5.
吩噻嗪和4-溴-4',4″-二甲基三苯胺经过C-N偶联反应合成中间体PZTA,进一步氧化得到给-受体(D-A)型目标化合物OPZTA。并对中间体和目标化合物进行了结构表征;用紫外-可见吸收光谱、荧光光谱研究了其光物理性能,结果表明,OPZTA有较好的发光性能,其固态下呈蓝色发光,溶液中有较强的分子内电荷转移。  相似文献   

6.
采用微波辐射方法,合成了一种新型的卟啉-蒽醌二元化合物,通过红外光谱、紫外-可见光谱、1HNMR对新化合物的结构进行了表征。探讨了蒽醌引入对化合物光谱性质的影响。吸收光谱显示:蒽醌引入扩大了化合物的共轭体系,紫外-可见吸收红移;荧光光谱表明:卟啉与蒽醌通过酰胺键连接形成共轭体系利于卟吩环激发态电子向蒽醌转移,导致荧光猝灭。  相似文献   

7.
设计和合成了一种双席夫碱。利用红外光谱对其结构进行表征,研究了其在不同溶剂中的紫外吸收光谱和荧光光谱,探究了过渡金属离子对紫外和荧光光谱的影响及聚集诱导发光(AIE)性质。结果表明,在不同溶剂中化合物的紫外光谱发生蓝移,荧光发射强度随溶剂极性增加强度减弱,且发生红移。通过紫外光谱和荧光光谱说明Fe~(3+)、Cu~(2+)在溶液中和化合物分子发生较强的相互作用,生成稳定配合物。同时该化合物没有表现出明显的AIE性质。  相似文献   

8.
应用圆二色光谱、紫外-可见吸收光谱、荧光光谱等实验研究在H2O溶液中钌(II)多吡啶配合物[Ru(phen)2(Hecip)](ClO4)2(phen=1,10-邻菲啰啉,Hecip=2(9-乙基-9H-咔唑-3-基)-1H-咪唑并[4,5-f][1,10]菲啰啉)与G-四链体DNA(AG3(T2AG3)3)相互作用。圆二色光谱实验表明,配合物能够诱导无序的G-四链体DNA以平行构型和反平行构型的共存体存在;从紫外和荧光滴定实验表明配合物与G-四链体之间存在较强的亲和力,拟合得到的结合常数可达106。  相似文献   

9.
应用圆二色光谱、紫外-可见吸收光谱、荧光光谱等实验研究在H2O溶液中钌(II)多吡啶配合物[Ru(phen)2(Hecip)](ClO4)2(phen=1,10-邻菲啰啉,Hecip=2(9-乙基-9H-咔唑-3-基)-1H-咪唑并[4,5-f][1,10]菲啰啉)与G-四链体DNA(AG3(T2AG3)3)相互作用。圆二色光谱实验表明,配合物能够诱导无序的G-四链体DNA以平行构型和反平行构型的共存体存在;从紫外和荧光滴定实验表明配合物与G-四链体之间存在较强的亲和力,拟合得到的结合常数可达106。  相似文献   

10.
L-B膜     
<正> L-B膜即 Langmuir-Blodgett单分子膜,它是人为地利用分子间相互作用而建立起来的特殊分子体系。在L-B膜中分子是有序的准晶体排列,其性质有别于固体和晶体,因而有人将其称为物质的第五相。用米制备L-B膜的技术称为L-B技术。  相似文献   

11.
A polyoxadiazole containing the 4-hydroxypyridine group, introduced to enhance the intermolecular interaction between polymer chains as well as for photosensitization, was synthesized from a corresponding precursor polyhydrazide. The absorption and emission spectra of the polymer film exhibited red-shifted maxima compared to those of the polyoxadiazole in chloroform solution, indicative of the presence of significant intermolecular interactions. The synthesized polymer showed a unique fluorescence enhancement upon UV irradiation in solution as well as in the film, presumably due to the photosensitized oxidation of hydroxypyridine groups to produce pyridone structures having different intermolecular interactions. Thus, this phenomenon enabled us to obtain a stable patterned image with enhanced fluorescence intensity in the UV-exposed area of the polymer film without any subsequent processes such as baking or etching.  相似文献   

12.
A dihydroxotin(IV) porphyrin functionalized single-walled carbon nanotubes (SWNTs) nanohybrid is obtained. Solubility of the nanohybrid in organic solvents is determined by UV-Vis-NIR absorption spectroscopy. Electron absorption and fluorescence spectra investigations demonstrate that efficient electron transfer occurs within the nanohybrid at the photoexcited state and the charge-separated state of the nanohybrid is observed by transient absorption spectrum. The results illustrate that this soluble electron donor–acceptor nanohybrid might be a good candidate as a light harvesting material in molecular photoelectronic devices.  相似文献   

13.
两亲性卟啉LB膜的Cu~(Ⅱ)离子嵌入作用   总被引:2,自引:0,他引:2  
黄涛  王永强 《化学世界》1999,40(10):520-523
研究了带一个脂链三个羟基( T H P P1)及三个脂链一个羟基( T H P P3)的两种卟啉的单层膜及 L B膜的 Cu2+ 离子嵌入作用。 Cu2+ 嵌入速率和程度取决于膜中卟啉环的取向、分子排列和聚集态。膜中卟啉环较为平躺、排列较疏松、形成 J 聚体的 T H P P1 可快速完全地金属化,而 T H P P3 在膜中形成 B 带劈裂聚集体,环较直立,排列紧密有序, Cu2+ 的嵌入缓慢且不完全。  相似文献   

14.
Jin Mizuguchi   《Dyes and Pigments》2006,70(3):226-231
Perylene pigments are known to exhibit a variety of shades in the solid state from vivid red, via maroon to black, although their solution spectra are quite similar. A second phase of the title compound (phase II) has newly been found when the single crystals were grown from the vapor phase. Phase II bears a black color while the previous phase (phase I) exhibits red-maroon. For this reason, the electronic structure of both phases has been investigated on the basis of the crystal structure as well as intermolecular interactions. In both phases, the absorption spectrum is composed of two bands: one is due to individual molecules (i.e. around 450–550 nm) and the second band arises from excitonic interactions between transition dipoles (i.e. around 600 nm in phase I and 625 nm in phase II). The intermolecular interactions along the stacking axis are primarily responsible for the appearance of the second band in both phases. Additionally, the interaction on the molecular plane is found to be slightly hypsochromic in phase I while bathochromic in phase II. This induces a difference in absorption maximum of the second band, leading to two different colors (red-maroon and black) in phases I and II.  相似文献   

15.
The novel porphyrin monomer 5-(4-acryloyloxylphenyl)-10,15,20-tris(4-carboxyphenyl)porphyrinate zinc(II) (ZnAOTCPP) and its corresponding sodium salt (ZnAOTCPP-Na) were synthesized. The latter compound exhibited a new band in excitation spectra due to formation of porphyrin aggregates in water, which were derived from its surface-activity when the concentration was higher than its critical association concentration (CAC). The porphyrins were copolymerized with acrylamide (AM) to prepare water-soluble copolymers with random and micro-blocky structures, which all displayed very new absorption and fluorescence emission bands in the long wavelength region compared with the porphyrin monomer. Furthermore, the micro-blocky copolymer exhibited an additional new absorption band at even longer wavelength region compared with the random copolymer. The experimental results and analysis showed that the porphyrin units in the random copolymer chains self-assembled to form porphyrin association complexes by hydrophobic association and π-π stacking interactions, and covalent restrictions of polymer chains in the micro-blocky copolymer.  相似文献   

16.
A porphyrin derivative, 5-(4-carboxylphenyl)-10,15,20-tris(4-chlorophenyl) porphyrin (PorCOOH), was synthesized and self-assembled as a monolayer thin solid film on the modified surface of a quartz substrate by an ester bond between –COOH groups of PorCOOH molecules and –OH groups of the hydrophilic pretreated SiO2 surface. An analysis of the spectral change revealed the J-aggregate nature of PorCOOH molecules in the obtained thin solid film. With this thin solid film of PorCOOH as a template, CdS nanoparticles were deposited on it in situ, which were further characterized by electronic absorption, fluorescence, and energy-dispersive X-ray spectroscopy. The morphology of CdS nanoparticles is disklike, and the diameter is ca. 40–60 nm, determined by scanning electronic microscopy. Furthermore, electron transfer between the organic layer and CdS nanoparticles was deduced through fluorescence quenching and theoretical analysis.  相似文献   

17.
A new kind of soluble copolymers incorporated anthracene and dialkyloxyl benzene moieties into main chain have been prepared by oxidative-coupling copolymerization. They were characterized by FT-IR, 1H NMR, UV-Vis, GPC, X-ray, thermogrametric analysis and fluorescence spectroscopy. The copolymers are amorphous and show excellent solubility in common organic solvents, such as chloroform. Thermogrametric analysis of the copolymers revealed that they have good stability with the onset decomposition temperature above 330 °C. The fluorescence spectra of the copolymers in solid state film display blue light emitting properties with the maximum at 468 nm.  相似文献   

18.
The complex Cu(I)(PPh3)2(oxinate) with oxine = 8-quinolinole is luminescent under ambient conditions. In the solid state it shows an emission which originates from the lowest-energy oxinate ILCT state. It consists of a fluorescence and a phosphorescence. In solution saturated with argon, a single broad emission band appears which seems to be composed of a more intense fluorescence and a much weaker phosphorescence at longer wavelength. If this solution is saturated with air, the complete emission band becomes less intense. This is quite surprising, since the oxinate ILCT fluorescence of other oxinate complexes is not quenched by oxygen. It is conceivable that the fluorescence largely consists of a delayed fluorescence. When the emitting triplet is depopulated by a thermally activated transition to the fluorescent singlet, both emissions, the delayed fluorescence and the phosphorescence, may undergo a luminescence quenching. For a simple comparison, the photoluminescence of Ag(PPh3)2(oxinate) was also briefly examined. The absorption and emission spectra of this silver complex in solution at r.t. resemble those of the copper complex.  相似文献   

19.
以邻苯二胺和丙二酸为原料,在3 mol/L盐酸催化下合成双(1H-苯并咪唑-2-基)甲烷中间体,然后与月桂醛通过Knoevenagel缩合反应合成了双苯并咪唑衍生物——1,1-双(1H-苯并咪唑-2-基)-1-十三碳烯。利用元素分析、FTIR和~1HNMR对合成产物的结构进行了表征,考察了常规碱催化剂对目标产物收率的影响,并通过UVVis和荧光光谱(FL)测定了目标化合物的光学性能。结果表明:六氢吡啶催化效果最好,产物收率可达76.33%。目标化合物在243、315和361 nm 3处有紫外吸收峰,可有效覆盖日光紫外线UVA和UVB波段;目标化合物溶液在λem=464.5 nm处有蓝紫色荧光,固体薄膜在λ_(em)=476.5 nm处有蓝紫色荧光,荧光量子产率为0.47。标题化合物荧光增白效果与常用荧光增白剂VBL相当。  相似文献   

20.
In this paper, in terms of the concentration of an aqueous solution of a surfactant, we investigate the self-assembly behavior of a porphyrin, 5, 10, 15, 20-tetra(4-pyridyl)-21H, 23H-porphine [H2TPyP], by using an oil/water system as the medium. We find that when a chloroform solution of H2TPyP is dropwise added into an aqueous solution of cetyltrimethylammonium bromide [CTAB] with a lower concentration, a large amount of irregular nanoarchitectures, together with a small amount of well-defined shuttle-like nanostructures, hollow nanospheres, and nanotubes, could be produced. While a moderate amount of shuttle-like nanostructures accompanied by a few irregular nanoarchitectures, solid nanospheres, and nanorods are produced when a CTAB aqueous solution in moderate concentration is employed, in contrast, a great quantity of shuttle-like nanostructures together with a negligible amount of solid nanospheres, nanofibers, and irregular nanostructures are manufactured when a high-concentration CTAB aqueous solution is involved. An explanation on the basis of the molecular geometry of H2TPyP and in terms of the intermolecular π-π interactions between H2TPyP units, and hydrophobic interactions between CTAB and H2TPyP has been proposed. The investigation gives deep insights into the self-assembly behavior of porphyrins in an oil/water system and provides important clues concerning the design of appropriate porphyrins when related subjects are addressed. Our investigation suggests that an oil/aqueous system might be an efficient medium for producing unique organic-based nanostructures.  相似文献   

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