酞菁氧钒分子及纳米簇在高定向石墨表面的自组装

报导了酞菁氧钒(VOPc)分子及其纳米簇在高定向石墨(HOPG)表面的自组装. 在室温下, 将HOPG浸入含有VOPc纳米簇(2-20 nm)和VOPc分子(约为10-3 g·L-1)的1,2-二氯乙烷胶体溶液中, VOPc分子在HOPG表面自组装形成单分子层(SAM), VOPc纳米簇在上述SAM表面进行尺寸选择性自组装. 组装于VOPc单分子层表面的纳米簇的粒径为(4.60±0.47) nm. 扫描隧道显微镜研究表明, 随着酞菁氧钒胶体溶液浓度由2.5×10^-2 g·L^-1增至2.5×10^-1 g·L^-1, 组装于SAM表面的VOPc纳米粒子的数量逐渐增多, 最终形成稠密的单层粒子组装体. 本文提供的自组装结构及方法在发展光电功能体系等方面具有潜在应用价值.     

两种晶型酞菁氧钒纳米颗粒的制备及形成机理

在水溶液中利用激光消融制备了酞菁氧钒(VOPc)相I型纳米颗粒，在加入一种非离子型表面活性剂的情况下通过激光消融制备得到了其相II型纳米颗粒.X射线衍射(XRD)、紫外可见吸收光谱(UV-Vis)和傅立叶变换红外光谱(FT-IR)表征了其纳米颗粒中的晶体结构.扫描电子显微镜(SEM)观察显示相I和相II型酞菁氧钒纳米颗粒的直径分别约为100和60 nm.对相II型酞菁氧钒纳米颗粒的形成机理进行了讨论.     

钒氧酞菁的合成及其薄膜结构与光电性能的研究

自从60年前^[1]金属酞菁被发现以来,就引起人们的广泛兴趣,其原因主要在于它们在染料颜料、光化学、催化、和成像中的应用. 和许多其它酞菁衍生物一样,钒氧酞菁具有光导和半导体特性,这使得它在光电子学、电子成像、化学传感器、甚至于微电子器件中有潜在的十分光明的应用前景^[2]. 例如, 钒氧酞菁在电子成像体系中已成为有用的感光材料. 近年来,金属酞菁等有机材料的结晶薄膜开始不断地吸引人们的注意力. 人们考察了不同的金属酞菁如: 酞菁铜、酞菁铅、酞菁镍、和酞菁锡 等的光电导和光电压^[3]. 通常酞菁以几种不同的多晶异构体、即以不同的晶体排列结构方式存在. 因此,其光电特性不仅取决于分子中心的金属原子、而且取决于它们的晶体结构. 总之,值得我们研究钒氧酞菁薄膜的光电特性以及它与吸收光谱和薄膜晶体结构的关系.     

Solvent-stabilized oxovanadium phthalocyanine nanoparticles and their application in xerographic photoreceptors

A stable organic sol of solvent-stabilized oxovanadium phthalocynine (VOPc) nanoparticles with excellent photoconductivity was successfully prepared by ultrasonificating a prepared nanoscopic VOPc powder in1,2-dichloroethane (C(2)H(4)Cl(2)) without any additive. These solvent-stabilized VOPc nanoparticles have a size distribution from 2 to 20 nm with an average diameter of 4.6 nm. The VOPc concentration of these organic sols could be as high as 100 g/L. The nanoscopic VOPc particles were well-dispersed in an insulating polycarbonate (PC) resin, resulting in single-layered photoreceptors with high surface charge durability in the dark and excellent photoconductivity. Based on the light-assisted scanning tunneling microscopy (STM) measurements, the charge transport mechanism of these photoreceptors was ascribed to light-induced enhancement of electron tunneling through the VOPc-nanoparticle/insulator junctions.     

Molecular orientation and interface compatibility for high performance organic thin film transistor based on vanadyl phthalocyanine

Organic thin film field-effect transistors (OTFTs) with mobility up to 1.0 cm2 V(-1) s(-1) and on/off ratio of 10(6)-10(8) as well as good environmental stability were demonstrated by using vanadyl phthalocyanine (VOPc), a pyramid-like compound with an ultra closely pi-stacked structure. The high performance, remarkable stability, low price, easy availability and nontoxicity of VOPc enabled it to be a promising candidate for OTFTs. Furthermore, we found that the mobility of the devices on OTS-modified Si/SiO2 substrates was 2 orders of magnitude higher than that of devices on Si/SiO2 substrates. Significantly, the relationship between field effect property and insulator surface property was explained from two new aspects of distribution of molecular orientation and interface compatibility, which might provide not only a useful model to explain why the surface modification with OTS could largely improve the field-effect performance but also a guide for rational optimization of device structure for higher performance. In addition, the field effect property of VOPc devices under vacuum, i.e., the oxygen doping effect on the VOPc devices, was measured. We found that the hole mobility decreased by several orders of magnitude with decreasing pressure. At a pressure below 10(-2) Pa, the device on OTS-modified substrates exhibited ambipolar conduction. These results indicated that the oxygen doping exerted essential effect on the field-effect property of VOPc, which was clearly distinct from that observed for pentacene-based OFETs.     

钒氧酞菁薄膜瞬态光电压性能的研究

本文分别用1064nm, 532nm和 355nm激发波长的YAG脉冲激光对所制备的phase Ⅱ结构钒氧酞菁膜Al\phase ⅡVOPc\ITO夹心电池进行瞬态光电压响应研究.随着3种波长激发光脉冲强度的增加, 瞬态光电压信号均增强. 激发光波长1064nm、532nm处于酞菁膜Q-带吸收区肩部, 光电压的极性与激发光入射方向无关, 均为负信号; 而激发光波长 355nm处于酞菁膜B-带, 光电压的极性与激发光入射方向有关, 从ITO极方向激发产生正电压信号, 从A1极激发产生负电压信号. 激发光波长对夹心电池的光电压产生有明显的作用, 光电压产生过程中应存在不同的机理. 这与前文^[1]对同一夹心电池稳态光电压响应研究所推断的结论一致.     

Highly enhanced visible-light photocatalytic hydrogen evolution on g-C3N4 decorated with vopc through π-π interaction

Photocatalytic H₂ evolution reactions on pristine graphitic carbon nitrides (g-C₃N₄), as a promising approach for converting solar energy to fuel, are attractive for tackling global energy concerns but still suffer from low efficiencies. In this article, we report a tractable approach to modifying g-C₃N₄ with vanadyl phthalocyanine (VOPc/CN) for efficient visible-light-driven hydrogen production. A non-covalent VOPc/CN hybrid photocatalyst formed via π-π stacking interactions between the two components, as confirmed by analysis of UV-vis absorption spectra. The VOPc/CN hybrid photocatalyst shows excellent visible-light-driven photocatalytic performance and good stability. Under optimal conditions, the corresponding H₂ evolution rate is nearly 6 times higher than that of pure g-C₃N₄. The role of VOPc in promoting hydrogen evolution activity was to extend the visible light absorption range and prevent the recombination of photoexcited electron-hole pairs effectively. It is expected that this facile modification method could be a new inspiration for the rational design and exploration of g-C₃N₄-based hybrid systems with strong light absorption and high-efficiency carrier separation.     

氧钒酞菁在激光光盘系统中的应用研究

氧钒酞菁在激光光盘系统中的应用研究董长征，沈永嘉，任绳武（华东理工大学精细化工研究所上海２００２３７）袁海俊（中国科学院上海光学精密机械研究所上海２０１８００）关键词：信息储存，激光光盘，功能染料，氧钒酞菁自１９７２年Ｐｈｉｌｉｐｓ公司推出激光光盘（...     

真空沉积酞菁铅和酞菁氧钒层状纳米复合膜的吸收光谱研究

有机光电材料在 2 0世纪 80年代后期得到了快速发展 ,与无机材料相比 ,它不仅价格低廉 ,易于加工 ,选择范围广 ,而且还可以通过分子结构的裁剪实现性能优化 [1～ 3 ] ,目前已成为光电导领域研究中的一个热点 .采用不同种类的化合物进行分子间复合能使材料的光电导性能得到一定程度的改善 [4 ,5] ,如提高光谱响应范围及调节禁带宽度 (用于激光器件的制造 )等 .本研究小组在真空蒸发沉积金属酞菁复合膜方面做了一些工作 ,发现真空共蒸发沉积的复合膜的吸收光谱相对于单一金属酞菁膜的吸收光谱有明显的加宽和红移现象 [6] .本文尝试用层状复合…     

H2Pc-VOPc二元体系的制备和表征

八十年代,国外Canon,IBM,HP,Ricoh,Xerox等公司开发出由计算机控制、数字扫描、激光成像的高分辨激光打印机,并逐渐占领市场。这种激光打印机具有印刷质量高、寿命长、印刷速度快、版面可任意调制、噪音小等特点。     

两种不同晶型酞菁氧钒的制备及其光导性

以不同方法制备了两种不同晶型的酞菁氧钒（ＶＯＰｃ），Ｘ－射线分析结果表明，一为多晶型，另一种为非晶型。两种晶型在红外区都具有光导性，非晶型的光导性更好。     

近红外敏感的功能分离型有机光接受体系的光导性能研究Ⅰ.酞菁氧钒晶粒尺寸对其体系光导性能的影响

激光打印和静电复印技术是当今信息处理、加工与传递的重要手段之一在这项综合性技术的发展中,光导材料的制备与选择一直是最为活跃的一个方面。近年来,激光打印机广泛使用半导体二极管激光打印头,其发射电磁波长在近红外区(780 nm~830 nm),要求对此范围敏感的新型光导材料满足其工作要求。     

The molecular structure, bonding, and energetics of oxovanadium phthalocyanine: an experimental and computational study

A mass spectrometric study of saturated vapor over oxovanadium phthalocyanine showed the thermal stability and monomeric vapor composition of this compound. The molecular structure of oxovanadium phthalocyanine (VOPc) was determined using a combination of gas-phase electron diffraction (GED), mass spectrometry, and quantum chemical calculations. According to GED, the VOPc molecule has C_4v symmetry. Experimental structural parameters are in good agreement with the parameters obtained by UB3LYP/cc-pVTZ calculations. The vanadium atom has a five-coordinated square-pyramidal geometry, being shifted above the plane of the four isoindole nitrogen atoms by 0.576(14) Å. The parameters of the square pyramid VN₄ are r _h1(V–N) = 2.048(7) Å, r _h1(N···N) = 2.780(12) Å. The vanadium–oxygen bond length is r _h1(V–O) = 1.584(11) Å. NBO analysis shows polar character of coordination bonds with significant covalent contribution and pronounced direct donation. X-ray crystallography and GED give different coordination bond lengths according to the different physical meaning of the parameters obtained by these methods. The enthalpy of sublimation [?H _s ^o (593–678 K)] is 53.3 ± 0.8 kcal/mol.     

Optically Active Oxo(phthalocyaninato)vanadium(IV) with Geometric Asymmetry: Synthesis and Correlation between the Circular Dichroism Sign and Conformation

Oxovanadium(IV) phthalocyanines (VOPcs) with a single‐handed rotation have been prepared, and their right‐ and left‐handed enantiomers resolved on a chiral HPLC column. These enantiomers gave circular dichroism (CD) spectra of opposite signs; the correlation between the CD sign and conformation was obtained by time‐dependent density functional theory (TDDFT) calculations: an enantiomer showing a negative sign in the Q band was suggested to be the right‐handed conformer viewing from the axial oxygen side, whereas that giving a positive CD sign was assigned to the left‐handed conformer. Although silicon phthalocyanines (SiPcs) with two different alkoxy axial ligands have been resolved similarly, the absence of a meaningful CD difference probably reflects the flat character of the SiPc plane compared to the VOPc plane. Changes in the Q‐band CD, depending on the relative orientation of the peripheral substituents, have been worked out theoretically and the origin of the chiroptical properties is discussed.     

Electronic transitions of vanadyl phthalocyanine in solution and in the solid state

The electronic absorption and luminescence of vanadyl phthalocyanine (Pc) in dilute solution. and solids at 300 K were measured and analyzed qualitatively with the Ake and Gouterman(AG) mode [1] and the exciton in molecular crystal model [2]. Good agreement between the group theoretical predictions and the observed spectra was found. The presence of trace aggregates in VOPc dilute solutions was clearly illustrated by their characteristic O-O fluoreseences. The dimer fluoresces on the high energy side of the monomer, whereas the signal from the heavier aggregates appears on the low energy side. The presence of an unpaired electron in the monomer results in a much smaller fluorescence yield as compared to the dimeric form in which the odd electrons are paired. The absorption and fluorescence vibronic progressions suggest that the monomer is quite stable upon optical excitation to the first excited singlet. Our spectra show that there are at least two crystal forms in the phase I solid in agreement with Griffiths et al.`s calorimetric observation [3]. One of the two forms is dimeric as proposed by Griffiths et al. and confirmed by us. The extremely low radiative yield of the dimeric form is attributed to ultrafast exciton migration and to the intrinsic low yield of the molecules. In the phase II crystal, two prominent electronic absorptions were predicted and assigned. The low luminescence yield of this phase is ascribed to the rapid ²Q ? ²T₁ relaxation which also leads to the greatly red shifted luminescence (i.e. ²T₁ → ²T) relative to the absorption, ²T → ²Q. Molecules in this phase are treated as monomeric rather than dimeric as in one of the phase I forms. Thus, the characteristics of the unpaired electron of the single molecule are preserved in the phase II crystal.     

Structure of the products of the photoreaction of osthole

The results are given of a study of the photoreaction of osthole in chloroform and acetophenone. It has been shown that when it is irradiated in the latter solvent the cyclization characteristic for coumarins takes place at the double bonds both in the 3,4- position of the coumarin ring and in the side chain, leading to the formation of cyclobutane structures.Leningrad Sanitary-Hygienic Medical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 165–168, March–April, 1980.     

缺Zn症患儿微量元素水平的样本特征分析及其临床补Zn治疗的评价

测定了150例缺Zn症患儿及健康儿发样中的Zn、Ca、Mg及Fe四元素水平．采用主成分分析法．将高维空间中的样本点映射到低维空间中来观察，研究其样本特征，评价临床补Zn治疗措施．结果瑶明：缺Zn症患儿体内缺Zn是病理的主要方面，但往往同时伴有其它微量元素水平偏低现象，临床缺Zn症状的表现可能为多种元素综合效应的反映．因此临床治疗不能单纯考虑朴Zn，还应结合患儿体内其他元素水平的具体情况，考虑其他元素的补给．治疗才能奏效显著．     

Thermodynamic parameters of solvation of nonelectrolytes in aqueous solutions of amides of carboxylic acids

Interaction and reorganization contributions to solvation enthalpies of nonelectrolytes in aqueous solutions of amides of carboxylic acids with different degree of N-substitution and N-methylpyrrolidone are calculated. The data are discussed using structurally thermodynamic characteristics of water-amide systems obtained by us previously. It is found that the type of concentration dependence of the solvation enthalpy of nonelectrolytes in all solutions investigated is determined by the type of reorganization component. It is shown that the highest solvation exothermicity of nonelectrolytes in water is due to the lowest value of the reorganization contribution in spite of that nonelectrolytes interact weaker with water than with non aqueous components.     

Effect of composition of coordination sphere on value of constant of additional hyperfine structure of EPR spectra

Conclusions Replacing the oxygen atoms by sulfur atoms in the coordination sphere of nitrogen-containing copper complexes leads to a substantial increase in the constant of the additional hyperfine structure from the nitrogen atoms, and consequently also to an increase in the degree of covalency of the Cu-N bonds.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 704–706, March, 1974.The authors thank V. I. Nefedov for taking the x-ray electronic spectra of compounds (I) and (II).     

Composition of lipids of the grain of opaque-2 maize

It has been established that the change in the composition of the total lipids and the fall in the fatty acid content depend on the initial maize genotype. A decrease in the amount of unsaponifiable substances in the grain of mutants is accompanied by qualitative changes in the composition regardless of the nature of the genotype.Scientific-Research Institute of Biology Dnepropetrovsk State university. Translated from Khimiya Prirodnykh Soedinenii. No. 3. pp. 360–363. May–June, 1988.