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131.
The title compound was prepared by reacting the anion of malononitrile with the corresponding ethanal, and characterised by UV–vis absorption spectroscopy, cyclic voltammetry and X-ray crystallography. Attachment of an additional ferrocenyl donor group to the π-donor–π-acceptor system does not enhance intramolecular charge transfer, because its bulk distorts the planarity of the conjugated chain.  相似文献   
132.
近年来,聚对苯乙炔(PPV)及其衍生物作为一类性能优良的电致发光材料而受到人们的广泛关注[1].这是因为聚合物发光材料能通过化学裁剪方法来改善发光效率、颜色、成膜性等特性.载流子形成激子以及激子的辐射和非辐射衰减过程向来是聚合物发光二极管(LEDs)发光的重要环节,因此研究聚合物的光物理过程对提高器件的发光特性是非常重要的.  相似文献   
133.
对谷氨酸与四氯对苯醌的荷移反应进行研究,确定了反应条件。在pH9.6硼砂缓冲溶液中,两者形成1∶1的络合物,其最大吸收波长为338nm,表观摩尔吸光系数为5.5×103L/mol.cm,线性范围为0~25μg/mL。该法用于测定味精中谷氨酸钠含量的测定,加标回收率为96.1%~101.8%,相对标准偏差不大于1.13%(n=6)。  相似文献   
134.
本文报道了用循环伏安法研究了几个 TTF 衍生物的电荷转移情况,发现都是两个单电子转移的可逆氧化还原波,其半波电位受溶剂的极性和电子效应影响较大,在 CH_2Cl_2溶液中,其 E_(1/2)大小顺序为:TMT-TTF相似文献   
135.
符史流  柴飞  陈洁  张汉焱 《物理学报》2008,57(5):3254-3259
利用高温固相反应法制备了Ca2Sn1-xCexO4和Ca2-ySrySn1-xCexO4一维结构发光体. XPS结果显示 Ca2SnO4拥有两种结合能分别为5277 eV和5293 关键词: 2Sn1-xCexO4')" href="#">Ca2Sn1-xCexO4 2-ySrySn1-xCexO4')" href="#">Ca2-ySrySn1-xCexO4 一维结构 电荷迁移光谱  相似文献   
136.
A new family of boron(III) chelates is introduced whereby molecular chirality, confirmed by circular dichroism, is imported during synthesis such that isolation of the diastereoisomers does not require separation procedures. The photophysical properties of two members of the family have been examined: the N,O,O-salicylaldehyde-based derivative shows pronounced intramolecular charge-transfer character in fluid solution and is weakly fluorescent, with a large Stokes shift. The corresponding 2-methylamino-benzaldehyde-derived N,N,O-chelate absorbs and fluoresces in the visible region with a much smaller Stokes shift. Orange fluorescence is also observed for this compound as a cast film. Temperature-dependence studies show that decay of the fluorescent state is weakly activated but emission is less than quantitative at 77 K. Quite rare for boron(III)-based chelates, this derivative undergoes intersystem crossing to form a meta-stable triplet-excited state. X-ray crystal structures are reported for both compounds, along with simulated ECD spectra.  相似文献   
137.
研究了特非那定与甲基红的电荷转移反应,建立了快速测定特非那定的可见分光光度法.结果表明,电荷转移络合物的络合比为1∶1,最大吸收波长是430nm,表观摩尔吸光系数为1.15×104 L·mol-1·cm-1.特非那定质量浓度在0.4~48mg/L范围内服从比耳定律,相关系数为0.998 9.当特非那定浓度为20mg/L时,6次测定结果的相对标准偏差为1.40%.本方法用于测定药物中特非那定的含量,加标回收率为97.8%和101.2%.  相似文献   
138.
The recent progress of charge-transfer complexes (CTCs) for application in many fields, such as charge transport, light emission, nonlinear optics, photoelectric conversion, and external stimuli response, makes them promising candidates for practical utility in pharmaceuticals, electronics, photonics, luminescence, sensors, molecular electronics and so on. Multicomponent CTCs have been gradually designed and prepared as novel organic active semiconductors with ideal performance and stability compared to single components. In this review, we mainly focus on the recently reported development of various charge-transfer complexes and their performance in field-effect transistors, light-emitting devices, lasers, sensors, and stimuli-responsive behaviors.  相似文献   
139.
Ultrafast optical control of intramolecular charge flow was demonstrated, which paves the way for photocurrent modulation and switching with a highly wavelength-selective ON/OFF ratio. The system that was explored is a fac-[Re(CO)3(TTF-DPPZ)Cl] complex, where TTF-DPPZ=4’,5’-bis(propylthio)tetrathiafulvenyl[i]dipyrido[3,2-a:2’,3’-c]phenazine. DFT calculations and AC-Stark spectroscopy confirmed the presence of two distinct optically active charge-transfer processes, namely a metal-to-ligand charge transfer (MLCT) and an intra-ligand charge transfer (ILCT). Ultrafast transient absorption measurements showed that the ILCT state decays in the ps regime. Upon excitation to the MLCT state, only a long-lived 3MLCT state was observed after 80 ps. Remarkably, however, the bleaching of the ILCT absorption band remained as a result of the effective inhibition of the HOMO–LUMO transition.  相似文献   
140.
Room-temperature phosphorescence (RTP) emitters have attracted significant attention. However, purely organic RTP emitters in red to near-infrared region have not been properly investigated. In this study, a series of naphthalenediimide−halobenzoate-linked molecules are synthesized, one of which exhibits efficient RTP properties, showing red to near-infrared emission in solid and aqueous dispersion. Spectroscopic studies and single-crystal X-ray diffraction analysis have shown that the difference in the stacking modes of compounds affects the optical properties, and the formation of intermolecular charge-transfer complexes of naphthalenediimide−halobenzoate moiety results in a bathochromic shift of absorption and RTP properties. The time-dependent density functional theory calculations showed that the formation of charge-transfer triplet states and the external heavy atom effect of the halogen atom enhance the intersystem crossing between excited singlet and triplet states.  相似文献   
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