具有Cn对称性的大分子的能带结构研究 1: 计算方法

利用环间和环内Bloch函数建立了一组新的原子轨道基函数。首次设计了适用于一维具有旋转对称性的大环分子的能带程序。计算了酞菁、四氮卟吩、四苯并卟啉, 四苯基卟啉的能带结构, 较好地解释了卟啉类化合物导电性能不如酞菁类的事实。还计算了酞菁铜和酞菁锰的能带结构, 讨论了酞菁与酞菁简化模型的能带结构以及晶体轨道的差异。     

具有Cn对称性的大分子的能带结构研究 1: 计算方法

利用环间和环内Bloch函数建立了一组新的原子轨道基函数。首次设计了适用于一维具有旋转对称性的大环分子的能带程序。计算了酞菁、四氮卟吩、四苯并卟啉, 四苯基卟啉的能带结构, 较好地解释了卟啉类化合物导电性能不如酞菁类的事实。还计算了酞菁铜和酞菁锰的能带结构, 讨论了酞菁与酞菁简化模型的能带结构以及晶体轨道的差异。     

四-4-(烷氧基-羰基)酞菁铜(Ⅱ)的合成、结构及其成膜性

本文合成了两种新型取代酞菁铜(Ⅱ)配合物:四-4-(戊氧基-羰基)酞菁铜(Ⅱ)(A)和四-4-(癸氧基-羰基)酞菁铜(Ⅱ)(B),并通过元素分析、ESR、~1H-NMR和FT-IR进行了表征.用可见光谱研究了它们在氯仿溶液中的聚集形式;用X-ray粉末衍射方法研究了配合物的固相堆积排列结构.两种配合物的氯仿溶液在亚相(水)上的π-A曲线表明,它们均有明显的“气”“液”“固”变化过程;并能在不同的表面压力区间形成较好的单分子层和多分子层膜.     

酞菁配合物对锂-亚硫酰氯电池正极的催化作用

合成过渡金属酞菁配合物MPc(M=Mn(Ⅱ),Fe(Ⅱ),Co(Ⅱ),N i(Ⅱ),Cu(Ⅱ)),研究MPc及其中心离子对L i/SOC l2电池正极的催化作用,并提出相关催化机理.     

酞菁金属配合物的合成及光谱特性研究

以4-叔丁基邻苯二甲酸酐、金属（Co3+、Al3+、Zn2+）氯化物、尿素、钼酸铵为原料,用固相合成法分别合成系列酞菁类金属配合物（MPc）。通过目标产物的红外谱图和紫外图,确定形成MPc;对合成的MPc的紫外可见吸收、荧光光谱特性进行研究,考察溶剂、浓度、中心金属对MPc化合物的光谱特性的影响,为光谱理论理解和实验教学提供桥梁。     

双酞菁铒的导电性

双酞菁稀土配合物具有夹心式结构,电导率较高,在有机半导体中有广阔的应用前景。作者曾测试了双酞菁稀土在酸性及碱性气氛中的电导率,发现其电阻率变化较大。用碘掺杂后电导率提高。Yamana等测得双酞菁钕在氢气和空气中的电阻率分别为1.1ΜΩ·cm和1.9ΚΩ·cm,认为双酞菁钕在空气中的低电阻率是吸附氧的缘故。但双酞菁镥在空气、     

高灵敏度高选择性气敏材料--金属酞菁配合物

酞菁配合物是一类重要的光电功能材料.由于它的特殊结构使其成为高灵敏度高选择性气敏材料,具有极好的应用前景.本文在介绍酞菁配合物的结构特点、合成方法、气敏特性及其最新研究进展的基础上,讨论了酞菁配合物的气敏机理及膜结构、中心金属和取代基对气敏性的影响,并对酞菁配合物作为气敏材料的发展趋势进行了展望。     

萘酞菁类配合物的气敏特性

在阐述了萘酞菁配合物的结构特点和气敏机理的基础上,讨论了影响萘酞菁配合物气敏性的主要因素,介绍了近年来萘酞菁配合物气敏物特性研究的最新进展,并对萘酞菁配合物作为气敏材料的发展趋势进行了展望。     

磺化2,3-萘酞菁锌(Ⅱ)、钴(Ⅱ)的电子吸收光谱和荧光光谱的研究

研究了磺化2，3-萘酞菁锌(Ⅱ)、钴(Ⅱ)在DMF(N，N-二甲基甲酰胺)、DMSO(二甲基亚砜)、乙醇、水等溶剂中的电子吸收光谱和荧光光谱．萘酞菁配合物的Q带与相应的酞菁配合物Q带相比，电子吸收光谱红移80～90nm，荧光光谱红移约100nm，荧光强度也显增加．在金属萘酞菁中引入磺酸基，配合物的电子吸收光谱Q带发生红移，但是影响不大、对于相同中心金属的配合物，改变溶剂的种类对配合物的电子吸收光谱的Q带影响较大．在金属萘酞菁环上引入一个磺酸基时，在相同溶剂中与无取代萘酞菁相比发生荧光光谱Q带红移，荧光强度增大．但在萘酞菁环上继续引入磺酸基时，荧光强度反而减少．磺化萘酞菁钴比磺化萘酞菁锌有较大的荧光强度．不同浓度下的电子吸收光谱和荧光光谱说明金属萘酞菁有集聚倾向、能形成基激缔合物．     

稀土酞菁配合物的XPS研究

本文合成了一系列稀土单酞菁配合物Lnpc(0AC)2,和Lnpccl(Ln=Tb,Ho, Tm, Lu,Pc为酞菁根, OAC为乙酸根)并用XPS较详细地研究了它们的电子结构, 讨论了它们的化学键性质和组成。     

含空位和杂质缺陷的LiFePO4电子结构的第一性原理计算

采用基于密度泛函理论的第一性原理研究了含空位和杂质缺陷的LiFePO_4电子结构,通过能带、态密度、布居分布分析,阐明缺陷及阴离子掺杂对材料电化学性能的影响,为LiFePO_4的结构设计和实验研究提供理论基础。结果表明,Li、Fe和O空位型缺陷对LiFePO_4的带型变化影响较小,禁带中无新的导带,禁带宽度有一定程度缩小,有利于电子的传导,但总能量上升,造成结构的不稳定性,在实际高温制备过程中,可能产生少量杂相,影响LiFePO_4正极材料的电化学性能;P空位缺陷对LiFePO_4的带型影响同样较小,但在禁带中产生了两条新的导带,禁带宽度明显变窄,有利于电子的传导,虽然总能量上升,造成结构的不稳定性,但在实际高温制备过程中,可能产生微量有利于电化学性能的杂相;F掺杂LiFePO_4的带型出现了明显的变化,半导体类型由p型转变为n型,极大地促进了电子的导电性,总能量下降,结构稳定,对LiFePO_4正极材料的电化学性能有正面的影响。     

Conductivity of One-Dimensional Phthalocyanine Compounds

Phthalocyanine, compounds(MPcL) containing the bridge radical ligand were studied by using the method of EHMOACC. Calculation results indicate that the charge carriers are mainly from thermal excitation of semiconductor, where charges are transferred by both hole and electron; the information manifested in the electron energy band and electric conductivity deduced by means of migration formula of the charge carrier at room temperature are in accordance with the experiment facts in the main.     

从二聚体到长链体系 I: 一种理解和获得-维能带的近似方法

将二聚体的分子轨道看作Bloch函数受微扰的结果, 对其能级作赝同相和赝反相分类, 获得的一维近似能带与晶体轨道计算得到的能带定性趋势完全一致. 以[Pt(CN)4^2^-]及聚乙炔为代表示范了应用, 表明从二聚体获得长链体系能带与性能的主要信息是可能的.     

MTDTPY.TCNQ及MTDTPY.CHL电荷转移复合物晶体的电子能带结构 及其与导电性能 关系的研究

用紧束缚近似的EHMO方法对αMTDTPY.TCNQ(1)、β-MTDTPY.TCNQ(2)及MTDTPY.CHL(3)三种电荷转移复合物晶体的电子能带进行了计算。在1中,电子施体(D)分子MTDTPY及受体(A)分子TCNQ形成交替重叠的一维分子柱(M),柱间无净电荷转移。能隙E~G=0.15eV,载流子的产生主要来自热激发。在2及3中,电子施体(D)MTDTPY及受体(A)TCNQ及CHL分子分别相对独立的D及A一维分子柱,载流子的产生主要来自柱间的电荷转移。由电子能带结构及关于载流子迁移的Frohlich-Sewell公式,得出上述三种晶体的室温电导率之比为σ1:σ2:σ3=3.75×10^-^1^0:1:1.15,与实验事实基本一致。关于各分子柱对σ的贡献,2中D柱:A柱～10^3:1;3中D柱:A柱～2:1。根据计算结果,本文还对载流子的迁移机理进行了讨论。     

[Co(C~5H~5)~2]~n.[M(dmit)~2](M=Ni,Pd;n=0,1,2)型配合物的合成及表征

二茂金属[M'(C~5H~5)~2]^1^+的盐与(NBu~4)~n[M(dmit)~2](M=Ni, Pd; N=1,2)反应, 当M'=Fe, Ni; n=1时, 分别得到了导电配合物[Ni(dmit)~2]和[Pd(dmit)~2]; 当M'=Co, n=1,2时, 分别得到的是电荷几乎不转移的4个盐[Co(C~5H~5)~2]~n[Ni(dmit)~2]和[Co(C~5H~5)~2]~n[Pd(dmit)~2]。用ESCA、Raman谱及循环伏安图讨论了上述化合物形成时的电荷转移量。尽管[M(dmit)~2]的室温电导率相当大, 但其电导率随温度的变化曲线表明它们属于半导体。EHCO能带计算给出[Ni(dmit)~2]的能隙0.112eV, 与实测的电导活化能相当接近。     

Metallophthalocyanines photosensitize the breakdown of (hydro)peroxides in solution to yield hydroxyl or alkoxyl and peroxyl free radicals via different interaction pathways

Interactions of organic peroxides (R'OOR) and hydroperoxides (R'OOH), including H2O2, with excited triplet and singlet state metallophthalocyanines (MPc, M = Zn, Al) have been studied by T-T absorption decay and fluorescence quenching. The ensuing photochemical processes result in decomposition of (hydro)peroxides as assessed by photo-EPR (electron paramagnetic resonance) and spin trapping. In argon-saturated apolar solutions and low MPc concentrations, alkoxyl free radicals (*OR) were identified as the primary products of (hydro)peroxide breakdown. Similarly, photosensitized decomposition of symmetric disulfides results in the formation of sulfur-centered radicals. In air-free aqueous solutions, ROOH photosensitization always gave rise to a mixture of hydroxyl and peroxyl radical (*OOR) adducts in varying molar ratios. At high MPc concentrations, both in polar and in apolar solutions, the most abundant products of ROOH decomposition were identified as *OOR. This indicates a change in the predominant interaction pathway, most likely mediated by MPc exciplexes and involving H-atom abstraction from ROOH by MPc-cation radicals. The prevalence of MPc singlet vs. triplet state interactions was confirmed by the much higher singlet quenching rate constants (log kq up to 9.5; vs. log kT < or = 4.5). In contrast to the triplet quenching, singlet quenching rates were found to depend on the (hydro)peroxide structure, following closely the trend of varying *OR yields for different substrates. Thermodynamic calculations were performed to correlate experimental results with models for electronic energy and charge transfer processes in agreement with the Marcus theory (Rhem and Weller approximation) and Savéant's model for a concerted dissociative electron transfer mechanism.     

还原态卤代聚苯胺能带结构及掺杂导电机理的研究

用ＥＨＭＯ－ＣＯ方法研究了卤代聚苯胺的能带结构及其掺杂导电机理，结果表明，在掺杂态卤代聚苯胺中形成单极化子晶格；取代主要通过改变带宽影响电导率，由掺杂而大幅度地提高了电导率是因为大大缩小了带隙，并进一步证实了外层ｄ轨道的成键作用。     

Relaxation dynamics of the hydrated electron: femtosecond time-resolved resonance Raman and luminescence study

Femtosecond time-resolved resonance Raman measurements were carried out to examine the relaxation process of the hydrated electron in water. The rise of the intra- and intermolecular vibrational Raman bands of the solvating water molecules was successfully time-resolved with a time resolution as high as 250 fs. The temporal intensity change of Raman bands, as well as that of luminescence background, was compared with the time evolution of the transient absorption signal. It was found that (1) the Raman and luminescence signals exhibited the same temporal behavior, (2) the rise time of the Raman bands is faster than the appearance of the equilibrated hydrated electron, indicating that the precursor state also gives rise to resonance Raman signals, and (3) the rise of the transient Raman band is slower than that of the transient absorption at the probe wavelength of 800 nm. Because it has been shown that the Raman intensity enhancement arises from the resonance with the s --> p transition, fact 2 implies that the precursor state is the nonequilibrated s-state electron. The delayed rise of the Raman signal compared to the absorption was explained in terms of the temporal change of the resonance condition. In very early time when the absorption is largely red-shifted, the probe at 800 nm is resonant with the high energy part of the absorption that provides little resonance Raman enhancement. This explanation was consistent with the probe wavelength dependence of the temporal behavior of the Raman signal: the Raman bands measured with the higher energy probe (600 nm) rose even more slowly. The resonance Raman signal in the anti-Stokes side was also examined, but no anti-Stokes band was observable. It suggests that the temperature increase of the solvation structure around the nonequilibrated hydrated electron is less than 100 K.     

Photoinduced Charge‐Carrier Generation in Epitaxial MOF Thin Films: High Efficiency as a Result of an Indirect Electronic Band Gap?

For inorganic semiconductors crystalline order leads to a band structure which gives rise to drastic differences to the disordered material. An example is the presence of an indirect band gap. For organic semiconductors such effects are typically not considered, since the bands are normally flat, and the band‐gap therefore is direct. Herein we show results from electronic structure calculations demonstrating that ordered arrays of porphyrins reveal a small dispersion of occupied and unoccupied bands leading to the formation of a small indirect band gap. We demonstrate herein that such ordered structures can be fabricated by liquid‐phase epitaxy and that the corresponding crystalline organic semiconductors exhibit superior photophysical properties, including large charge‐carrier mobility and an unusually large charge‐carrier generation efficiency. We have fabricated a prototype organic photovoltaic device based on this novel material exhibiting a remarkable efficiency.     

Correlation between molecular orbitals and doping dependence of the electrical conductivity in electron-doped metal-phthalocyanine compounds

We have performed a comparative study of the electronic properties of six different electron-doped metal-phthalocyanine (MPc) compounds (ZnPc, CuPc, NiPc, CoPc, FePc, and MnPc), in which the electron density is controlled by means of potassium intercalation. Despite the complexity of these systems, we find that the nature of the underlying molecular orbitals produces observable effects in the doping dependence of the electrical conductivity of the materials. For all the MPc's in which the added electrons are expected to occupy orbitals centered on the ligands (ZnPc, CuPc, and NiPc), the doping dependence of the conductivity has an essentially identical shape. This shape is different from that observed in MPc materials in which electrons are also added to orbitals centered on the metal atom (CoPc, FePc, and MnPc). The observed relation between the macroscopic electronic properties of the MPc compounds and the properties of the molecular orbitals of the constituent molecules clearly indicates the richness of the alkali-doped metal-phthalocyanines as a model class of compounds for the investigation of the electronic properties of molecular systems.