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螺噁嗪光致变色反应机理研究进展 总被引:2,自引:0,他引:2
20世纪80年代中期以来, 关于螺噁嗪在光致变色过程中的光化学和光物理现象的研究非常活跃. 综述了近20年来对溶液中的螺噁嗪、晶体螺噁嗪以及固体介质中的螺噁嗪的光致变色机理研究结果, 同时介绍了实验研究方法和理论研究方法在螺噁嗪光致变色过程研究中的应用, 分析了取代基对光致变色性质的影响. 阐述了机理研究对新型螺噁嗪设计合成的重要指导意义. 相似文献
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本文合成了 4种螺噁嗪类化合物,并通过FTIR、1H NMR、ESI-MS对其结构进行了表征.研究了吲哚环上氮原子和噁嗪环9'位不同的取代基及溶剂化效应对其光致变色性能的影响.结果表明,吲哚环的氮原子引入体积较大的基团对螺噁嗪最大吸收波长无明显影响,然而有利于开环体的稳定性,且溴原子的引入会影响螺噁嗪的光响应性;噁嗪环... 相似文献
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在超声波辐射条件下,以Fischer碱、1-亚硝基-2,7-二羟基萘为原料,无水乙醇为溶剂快速合成了三个螺嗪类光致变色化合物,通过1 H NMR、IR对目标产物的结构进行了表征,讨论了超声辐射时间对合成产率的影响,利用超声波法合成螺噁嗪类光致变色化合物反应速率快、产率有所提高. 相似文献
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制备了含有螺噁嗪(SO)化合物的紫外光固化丙烯酸聚氨酯清漆(UV-PUA)膜, 研究了SO在该清漆中的光致变色性能, 并与其在聚甲基丙烯酸甲酯(PMMA)中的光致变色性能进行了比较. 结果发现, 紫外光固化螺噁嗪丙烯酸聚氨酯清漆(UV-SO-PUA)膜在紫外光固化过程中逐渐由无色变为蓝色和紫色, 撤去紫外光源, 漆膜退色至粉色, 且固化后的漆膜在粉色和紫色之间可逆变化; 而SO-PMMA膜在无色和蓝色之间可逆变化. 紫外光激发的UV-SO-PUA膜的紫外-可见吸收光谱可见光区出现了明显的双重吸收峰(520和600 nm), 而在PMMA中仅出现单峰. SO开环体在UV-PUA 中室温稳定性优于其在PMMA中的稳定性. SO在UV-PUA膜中的抗疲劳性能与其在PMMA中相比显著提高, 紫外光照射16 h, UV-SO-PUA漆膜未出现疲劳现象. SO在UV-PUA膜中表现出了优良的光致变色行为. 相似文献
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A series of coumarin derivatives obtained from salicylaldehyde and phenol were synthesized. Their corresponding terbium complexes were prepared and characterized by elemental analysis, EDTA titrations, molar conductivity, UV–vis spectra, IR spectra, and thermal analysis. The luminescent properties and electrochemical properties of the terbium complexes were also investigated. The results showed that all the terbium complexes exhibited characteristic emissions of terbium ions. The introduction of electron-donating groups can improve the luminescent properties, decrease the HOMO and LUMO energy levels of the terbium complex, while electron-withdrawing groups can weaken the luminescent properties, and increase the HOMO and LUMO energy levels of terbium complex. 相似文献
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二茂铁及其衍生物的电化学特性与结构理论研究 总被引:1,自引:0,他引:1
研究了二茂铁及其衍生物(甲酰二茂铁,乙酰二茂铁,甲醇二茂铁和乙酸二茂铁)的电化学行为,运用结构理论给出了二茂铁D5点群群轨道能级图与二茂铁衍生物的前线轨道能级图,得出在二茂铁分子结构中1e2(dx2-y2,dxy)与3a1(dz2,4s)分别属于分子前线轨道中的HOMO和LUMO。同时用密度泛函理论(DFT)在LANL2DZ基组水平上对其结构进行了全优化,得到了二茂铁及其衍生物前线最高被占轨道(HOMO)能量值,Fe原子净电荷,对其电化学行为与前线轨道能级相对大小进行了验证。 相似文献
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Chuandong Dou Zicheng Ding Zijian Zhang Zhiyuan Xie Jun Liu Lixiang Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(12):3719-3723
The key parameters of conjugated polymers are lowest unoccupied molecular orbital (LUMO) and highest occupied molecular orbital (HOMO) energy levels. Few approaches can simultaneously lower LUMO and HOMO energy levels of conjugated polymers to a large extent (>0.5 eV). Disclosed herein is a novel strategy to decrease both LUMO and HOMO energy levels of conjugated polymers by about 0.6 eV through replacement of a C C unit by a B←N unit. The replacement makes the resulting polymer transform from an electron donor into an electron acceptor, and is proven by fluorescence quenching experiments and the photovoltaic response. This work not only provides an effective approach to tune the LUMO/HOMO energy levels of conjugated polymers, but also uses organic boron chemistry as a new toolbox to develop conjugated polymers with high electron affinity for polymer optoelectronic devices. 相似文献
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Developing Conjugated Polymers with High Electron Affinity by Replacing a CC Unit with a B←N Unit
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Dr. Chuandong Dou Dr. Zicheng Ding Zijian Zhang Prof. Zhiyuan Xie Prof. Jun Liu Prof. Lixiang Wang 《Angewandte Chemie (International ed. in English)》2015,54(12):3648-3652
The key parameters of conjugated polymers are lowest unoccupied molecular orbital (LUMO) and highest occupied molecular orbital (HOMO) energy levels. Few approaches can simultaneously lower LUMO and HOMO energy levels of conjugated polymers to a large extent (>0.5 eV). Disclosed herein is a novel strategy to decrease both LUMO and HOMO energy levels of conjugated polymers by about 0.6 eV through replacement of a C? C unit by a B←N unit. The replacement makes the resulting polymer transform from an electron donor into an electron acceptor, and is proven by fluorescence quenching experiments and the photovoltaic response. This work not only provides an effective approach to tune the LUMO/HOMO energy levels of conjugated polymers, but also uses organic boron chemistry as a new toolbox to develop conjugated polymers with high electron affinity for polymer optoelectronic devices. 相似文献
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Adelio R. Matamala Alejandro A. Alarcón 《International journal of quantum chemistry》2012,112(5):1316-1322
A simple model for the calculation of HOMO and LUMO energy levels of benzocatafusenes (i.e., molecules that are only constituted by mutually condensed benzene rings and without interior carbon atoms, which belong to three benzene rings) is presented. Using semiempirical AM1 method, 615 benzocatafusenes were studied (29 normal and 586 branched). The relation between energy and molecular structure was coded by the three Hückel parameters: Coulomb integral, bond integral, and secular x eigenvalue. Analytical functions for HOMO and LUMO energy levels in terms of x parameter were obtained for normal benzocatafusenes, and energies for branched benzocatafusenes were satisfactorily modelled by the introduction of a simple correction function into the analytical functions describing normal benzocatafusenes. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012 相似文献
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吡唑啉衍生物的电化学性质及其能带结构 总被引:1,自引:0,他引:1
有机 /聚合物电致发光是当今世界上的热门研究领域[1 ,2 ] ,因而有机 /聚合物电致发光材料的能带结构成为非常重要的研究课题[3] .目前 ,确定有机 /聚合物电致发光材料的能带结构的方法主要有电化学法[4] ,光谱法[5] ,量子化学计算法[6] ,紫外光电子能谱法[7] ,光电子发射法[8] 等 .这些方法中 ,由于电化学方法操作简单 ,对仪器设备要求不高 ,故被广泛使用 .虽然不同的测试方法测得的能带数据存在一定的系统误差 ,但由于电发光器件中考虑的是材料间的能带匹配 ,因此 ,在不同的条件下测定的能带数据相对来说是可信的 .吡唑啉化合物具有较高的… 相似文献
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The analysis of the through-space/bond interaction with
calculation is applied to the HOMO energy levels of propellane compounds. We could investigate molecular structural factors which dominate the height of the HOMO energy levels. 相似文献
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Meijuan Lin Qiang Tang Huijuan Zeng Guang Xing Qidan Ling 《Russian Journal of General Chemistry》2016,86(7):1747-1752
Several new Ir(III) complexes with 2-(4-bromophenyl)-1H-benzo[d]imidazole or 2-(4-bromophenyl)- 1-methyl-benzo[d]imidazole ligands as cylcometalated ligand and acetylacetonate or picolinate as the ancillary ligand were synthesized and their structures and photophysical properties were characterized. HOMO and LUMO energy levels and the molecular structures of Ir(III) complexes were scrutinized by DFT calculations. The complexes exhibited green luminescence at the maximum emission peaks at ca 495–522 nm. The methyl group substituent and replacing of acetylacetonate with picolinate complex can enhance the complex thermal stability. HOMO energy levels of the complexes vary from –4.99 to –5.44 eV, the LUMO energy levels are between –1.52 and –1.97 eV. 相似文献
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Dong Lu Xiao-Chun Yang Bing Leng Xiao-Di Yang Cong-Wu Ge Xue-Shun Jia Xi-Ke Gao 《中国化学快报》2016,27(7):1022-1026
A series of core-expanded naphthalene diimides (NDI-DTYM) and thiophene-based derivatives (1a-c) were designed and synthesized to investigate the relationship between molecular structures and the highest occupied molecular orbital (HOMO) energy levels but has little impact on the lowest unoccupied molecular orbital (LUMO) energy levels. The results demonstrated that increasing the number of thiophene units can gradually elevate the HOMO energy levels but had little impact on the LUMO energy levels. The n-channel organic field-effect transistors (OFETs) based on 1b and 1c have demonstrated that these almost unchanged LUMO energy levels are proper to transport electrons. 相似文献