共查询到19条相似文献,搜索用时 125 毫秒
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在杂化密度泛函水平上,利用响应函数方法,计算了一类四苯基乙烯衍生物的双光子吸收性质.考虑了四苯基乙烯上给电子基团的位置和数目对双光子吸收性质的影响.并且,根据实验者采用的分子,通过增加分子的平面性和共轭长度,以及增强给体强度,理论设计了三种分子结构,并计算了它们的双光子吸收性质.结果表明,给体位置和数目对双光子吸收性质有重要影响.位于分子末端的给体取代基能有效提高双光子吸收强度.随着给体数目的增加,双光子吸收波长发生红移.在四苯基乙烯的不同侧位上添加给体取代基对双光子吸收性质的影响有明显差异.与实验者采用的分子相比,理论设计的分子结构双光子吸收截面均明显增大.当三苯胺基代替四苯基乙烯基之后,双光子吸收峰发生较大红移,双光子吸收截面明显增大. 相似文献
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设计合成了一种A-π-D-π-A型的双光子荧光染料3,6-双(4-乙烯基苯腈)-9-乙基咔唑,测试了其在二氯甲烷(DCM)、乙酸乙酯(EA)、乙醇(Et OH)、乙腈(ACN)、二甲亚砜(DMSO)和磷酸缓冲盐溶液(PBS)等不同溶剂中的紫外吸收光谱、单光子及双光子荧光光谱。化合物3,6-双(4-乙烯基苯腈)-9-乙基咔唑在紫外吸收光谱中存在两个相似的特征吸收带并呈现出复杂的溶剂化效应,在DMSO中具有最大荧光量子产率(86.02%),其相应的活性吸收截面为12.56 GM。在双光子荧光成像方面,染料分子具有优良的细胞膜通透性并且在双光子荧光显微镜下呈现出明亮的绿色荧光,表现出较好的双光子荧光成像性能。这些数据表明,化合物3,6-双(4-乙烯基苯腈)-9-乙基咔唑可用作一种较为理想的双光子荧光标记染料。 相似文献
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在密度泛函理论理论水平上,采用响应理论方法计算了一系列2,6-donor-acceptor二噻吩并磷杂茂衍生物分子的单、双光子吸收性质.理论计算结果表明该系列分子都具有较大的双光子吸收截面,并且分子中心的磷原子无论被氧化还是金属配合,其双光子吸收截面几乎保持不变.此外,还考虑了溶剂效应对分子光学性质的影响,研究表明分子能级发生了溶剂化蓝移,并且分子的单光子和双光子吸收性质随着溶剂极性表现出非单调变化. 相似文献
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在密度泛函理论理论水平上,采用响应理论方法计算了一系列2,6-donor-acceptor 二噻吩并磷杂茂衍生物分子的单、双光子吸收性质. 理论计算结果表明该系列分子都具有较大的双光子吸收截面,并且分子中心的磷原子无论被氧化还是金属配合,其双光子吸收截面几乎保持不变. 此外,还考虑了溶剂效应对分子光学性质的影响,研究表明分子能级发生了溶剂化蓝移,并且分子的单光子和双光子吸收性质随着溶剂极性表现出非单调变化. 相似文献
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理论研究分子结构与双光子吸收性质之间的关系对于指导实验者设计与合成功能分子材料具有重要意义. 在杂化密度泛函水平上, 利用响应函数方法, 计算了一类以二乙烯硫/砜基为中心的新型电荷转移分子的双光子吸收截面, 并在相同计算水平上, 与联苯乙烯类强双光子吸收分子做了比较; 以新型电荷转移分子为基础, 利用异构效应, 设计出了可以增强双光子吸收强度的分子结构. 研究表明, 在可应用波长范围内, 该系列分子表现出较强的双光子吸收响应, 与相似共轭长度的强双光子吸收分子具有相同量级的双光子吸收截面; 二乙烯硫/砜基在分子中心作为吸电子基团可以形成有效的电荷转移分子; 改变咔唑基的连接方式可以有效提高双光子吸收截面. 该研究为实验合成新型双光子吸收分子材料提供了理论依据. 相似文献
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利用时域有限差分法数值求解速率-场强方程,研究了一系列共价连接的氧化石墨烯-卟啉复合材料在纳秒时域内的光限幅性质和双光子吸收. 计算结果表明,氧化石墨烯-卟啉复合分子与单独的卟啉分子相比展现出增强的光限幅效应,并且有着更大的双光子吸收截面.与之前得到的含重金属的卟啉分子具有更强非线性光学性质的结论不同,不含金属元素的卟啉分子与氧化石墨烯结合后展现出了更强的非线性光学性质. 理论计算的结果与实验测量符合较好. 此外,着重研究了介质的厚度和脉冲宽度对分子双光子吸收截面的影响. 结果表明,随着介质厚度的增加或者脉宽的变宽分子的动态双光子吸收截面增大. 相似文献
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双光子技术的应用研究进展 总被引:2,自引:0,他引:2
双光子技术在未来光电子集成、生物分子探测、医学诊断等领域具有巨大应用潜力和广阔应用前景。文章着重介绍了双光子过程在荧光显微成像、高密度数据存储以及微细加工等领域的应用研究进展。对影响双光子技术的应用和发展的相关领域的研究动态也进行了简要讨论。 相似文献
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Fuat Bayrakceken 《Journal of luminescence》1984,29(1):111-118
A number of photophysical properties of rubreneperoxide have been measured for the first time including the two-photon absorption, fluorescence, delayed fluorescence, and triplet-triplet absorption spectra. Singlet and triplet decay parameters of this molecule have also been measured. Three different photoperoxides of rubrene are formed. The results are discussed and compared to those of molecules. 相似文献
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Recently introduced bioaffinity assay technology, ArcDia TPX, is based on two-photon excited fluorescence (TPE) and it enables separation-free ultra-sensitive immunoassays from microvolumes. Here we present syntheses of novel two-photon excitable fluorescent labeling reagents which have been specially designed to be used as label molecules in the ArcDia TPX assay technique. The labeling reagents are based on dipyrrylmetheneboron difluoride (dipyrrylmethene-BF2) chromophore, which have been substituted with aryl, heteroaryl or arylalkenyl chemical groups to extend the pi-electron conjugation. These substitutions results in a series of dipyrrylmethene-BF2 fluorophores with different photophysical properties. Dipyrrylmethene-BF2 fluorophores have been further substituted with a dipeptide linker unit and finally activated as succinimidyl esters to enable specific coupling with primary amino groups. The dipeptide linker serves as a spacer arm between the label and a target, and enhances the solubility of the label in aqueous solutions. Study of the chemical and photophysical performance of the new labeling reagents is described. The new labeling reagents exhibit high fluorescence quantum yields, and molar absorption coefficients. The results show that the new labels with the hydrophilic dipeptide linker unit provide large two-photon excitation cross-sections, high fluorescence quantum efficiency and good solubility in aqueous solutions. The results suggest that the novel dipyrrylmethene-BF2 labels are highly applicable to bioaffinity assays based on two-photon excitation of fluorescence. 相似文献
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Synthesis of Novel Carbazole based Styryl: Rational Approach for Photophysical Properties and TD-DFT
Nagaiyan Sekar Prashant G. Umape Shantaram Kothavale Mininath Deshmukh 《Journal of fluorescence》2014,24(5):1457-1472
The synthesis and solvatochromic behavior of four novel carbazole based fluorescent styryl dyes were explained. In chlorinated solvents such as DCM and chloroform, these dyes show bathochromic shift in their absorption as well as emission. The styryl dyes 6b and 6c show solid state yellow fluorescence. DFT and TD-DFT computations were performed to study structural, molecular, electronic and photophysical properties of these dyes. The computed absorption and emission wavelength values are found to be in good agreement with the experimental results. The photophysical properties of these 1-styryl carbazole dyes are also compared with the recently reported 3-styrl carbazole dyes. The unique behavior of dye 6d is well explained by its optimized geometry found in the excited state. Ratio of ground to excited state dipole moment of the synthesized novel styryl compounds were calculated by Bakhshiev and Bilot-Kawski correlations. 相似文献
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Valentyna P. Tokar Mykhaylo Yu. Losytskyy Tymish Y. Ohulchanskyy Dmytro V. Kryvorotenko Vladyslava B. Kovalska Anatoliy O. Balanda Igor M. Dmytruk Vadym M. Prokopets Sergiy M. Yarmoluk Valeriy M. Yashchuk 《Journal of fluorescence》2010,20(4):865-872
Spectral-fluorescent properties of benzothiazole styryl monomer (Bos-3) and homodimer (DBos-21) dyes in presence of DNA were
studied. The dyes enhance their fluorescence intensity in 2–3 orders of magnitude upon interaction with DNA. Studied styrylcyanines
in DNA presence demonstrate rather high values of two-photon absorption (TPA) cross-section, which are comparable with the
values of TPA cross section of the rhodamine dyes. An applicability of the styrylcyanines as probes for the fluorescence microscopy
of living cells was studied. It was shown that both dyes are cell-permeable but homodimer dye DBos-21 produces noticeably
brighter staining of HeLa cells comparing with monomer dye Bos-3. Molecules of DBos-21 initially bind to the nucleic acids-
containing cell organelles (presumable mitochondria) and are able to penetrate into the cell nucleus. Thus, homodimer styryl
DBos-21 dye is viewed as efficient stain for single-photon and two-photon excitation fluorescence imaging of living cells. 相似文献
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Alexander Patas Georg Achazi Nils Hermes Monika Pawłowska Albrecht Lindinger 《Applied physics. B, Lasers and optics》2013,112(4):579-586
We demonstrate selective excitation of dyes with overlapping absorption spectra in solution with pulses transmitted through a hollow-core fiber. Thereto we show how dispersive effects occurring in the fiber can be compensated and what the limiting pulse energies are. Furthermore, an overview over various phase parameterizations is given and we examine which are best used when optimizing a two-photon fluorescence contrast of two dyes in a sample. This could be relevant for future endoscopic applications as well as state of the art two-photon microscopy. 相似文献
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The photophysical properties of novel cyclic azacyanine derivatives have been investigated in acetonitrile, N-butyronitrile,
methanol, ethanol, DMF and water. Introduction of electron donating or accepting groups on the cyclic azacyanine has a direct
impact on the spectroscopic and photophysical properties. Irrespective of the nature of the substitution, azacyanine shows
a general solvent relaxation in accordance with Lippert-Mataga’s prediction; however, in protic solvent, specific interactions
are encountered. Fluorescence lifetime decay suggests a relaxation in the nanosecond time scale with monoexponential decay
in polar solvents and biexponential decay in non polar solvents. The fluorescence lifetime of azacyanines are found to be
longer than popular cy3 dyes. An electron donating substituent increases the fluorescence lifetime and influences the radiative
process, whereas an electron withdrawing group marginally increases the excited state lifetime but remarkably enhances the
radiative process. The fluorescence quantum yield of substituted cyclic azacyanine in water is noted to be at least five fold
higher than the popular cy3 dye. 相似文献
18.
Fluorescence of Styryl Dyes-DNA Complexes Induced by Single- and Two-Photon Excitation 总被引:1,自引:1,他引:0
Tokar VP Losytskyy MY Kovalska VB Kryvorotenko DV Balanda AO Prokopets VM Galak MP Dmytruk IM Yashchuk VM Yarmoluk SM 《Journal of fluorescence》2006,16(6):783-791
The series of novel monomer and homodimer styryl dyes based on (p-dimethylaminostyryl) benzothiazolium residues were synthesized and studied as possible fluorescent probes for nucleic acids
detection. Spectral-luminescent and spectral-photometric properties of obtained dyes in the unbound state and in DNA presence
were studied. Fluorescence emission induced by two-photon excitation of dye-DNA complexes in aqueous buffer solution was registered.
Two-photon absorption cross section values of the studied dyes in DNA presence were evaluated. 相似文献
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A. N. Sinel’nikov V. Ya. Artyukhov Yu. V. Aksenova R. T. Kuznetsova 《Optics and Spectroscopy》2012,113(3):291-297
The spectral and luminescence properties of a number of pyrromethene (PM) dyes have been investigated. The absorption and luminescence spectra of PM molecules in different solvents are measured. The electronic structure and electronic excited states are calculated by the method of intermediate neglect of differential overlap with special spectroscopic parameterization. The rate constants of photophysical processes are estimated, and the fluorescence quantum yields are calculated. The fluorescence quantum yields of PM I and PM II molecules are found to decrease upon their excitation to the second short-wavelength absorption band. This phenomenon is interpreted. 相似文献