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61.
采用了微机版的Gaussian 94程序以及CIS方法和CIS MP2方法对S2 分子的部分单重激发态和三重激发态进行了研究。计算表明 :CIS方法和CIS MP2方法对S2 分子的低单重激发态基本适用 ,可以给出较为满意的结果。但对S2 分子的三重激发态和高激发态 ,CIS方法还需进一步改进。  相似文献   
62.
Configuration interaction singles (CIS) calculations of the planar T1 state of hexatriene, octatetraene, decapentaene, and dodecahexaene showed that the (HOMO−i)→(LUMO+i) type single excitations contribute significantly. This is attributed to the similarity of the HOMO, LUMO, and HOMO−i, LUMO+i overlap densities which stem from nodal properties of the π molecular orbitals. CASSCF calculations for hexatriene and octatetraene also showed remarkable contributions of the (HOMO−i)→(LUMO+i) type singly excited configurations. © 1998 John Wiley & Sons, Inc. Int J Quant Chem 67: 101–106, 1998  相似文献   
63.
对利用CMOS图像传感器进行爆温测量的方法进行了理论和实验研究。提出了一种更符合实际测量要求的瞬时多光谱爆温测量系统,并用激光器的特征谱线对系统进行了标定。利用该装置结合多光谱色温回归计算方法,测量了温度快速变化的卤钨灯的温度,得到了其随时间的变化曲线。  相似文献   
64.
太阳电池新进展   总被引:16,自引:0,他引:16  
赵玉文 《物理》2004,33(2):99-105
介绍了各种太阳电池技术和发展概况 ,其中晶硅太阳电池技术发展比较成熟 ,商业化程度最高 ,许多技术和理论问题带有普遍性 ,对其他电池的研究开发有借鉴作用 ,文章对此作了较详细的介绍 .薄膜电池是未来发展方向 ,文章对目前国际上研究得最多的几种薄膜电池 ,如非晶硅 (a Si)、碲化镉 (CdTe)、铜铟硒 (CuInSe2 ,CIS)、多晶硅、染料敏化TiO2 等电池的技术发展概况作了介绍 ,并简要说明了不同电池的商业化生产情况 .  相似文献   
65.
利用密度泛函方法(DFT)和单激发组态相互作用(CIS)方法, 在6-31G(d,p) 基组水平下优化了咔唑分子和14种双咔唑结构异构体的基态和激发态结构, 在此基础上, 用含时密度泛函(TD-DFT)方法在相同基组水平下计算了模型分子的吸收和发射波长及电荷跃迁性质. 讨论了双咔唑构型的变化带来的性质上的变化, 与实验值相比得到了精确的计算结果. 通过双咔唑的前线轨道能量值、电离能和亲和势及重组能的变化, 全面研究了不同构型的应用, 为实验上的设计和合成提供了思路.  相似文献   
66.
四种黄酮类化合物荧光光谱的量子化学研究   总被引:1,自引:0,他引:1  
采用量子化学半经验方法RHF/PM3对四种黄酮类化合物的荧光光谱进行了理论研究。首先,采用能量梯度法对各化合物的构型进行了优化。所得结果表明,在4个化合物中,左侧两个六元环均在同一个平面内,而右侧苯环平面与该平面有大小不等的扭转角。对4个优化构型进行振动分析,均未出现虚频率,说明所得构型基本合理。在此基础上,采用单激发组态相互作用方法(CIS)计算荧光光谱,所有计算结果与实验值基本吻合。  相似文献   
67.
The structures of versatile diarylethene-containing 1,10-phenanthroline ligands (L1 and L2) and their rhenium(I) complexes [Re(CO)3(L)Cl] (1 and 2) in the ground and low-lying excited states have been optimized at the B3LYP functional and the ab initio configuration interaction singlets (CIS) level, respectively. The spectral properties are predicted with use of time-dependent density functional theory (TDDFT). As shown, the transition character of the strongest absorption band and luminescent spectrum for closed-ring complex 1 is different from that of 2, the former has ππ character and the latter has MLCT and LLCT character. We presume the second triplet excited state contributes to the phosphorescence of 1, while the lowest triplet excited state accounts for the phosphorescence of 2. Spin-orbit coupling influences the excitation energies for d(Re)-joined transitions whereas it has negligible effect on the transition character for complexes 1 and 2.  相似文献   
68.
The electronic structures and spectroscopic properties of a series of mixed bis-cyclometalated iridium(III) complexes [Ir(ppy)2X2] (X = CN, 1; X = NCS, 2; X = NCO, 3; ppy = 2-phenylpyridl) were investigated at the B3LYP/LANL2DZ and CIS/LANL2DZ levels. The calculated geometry parameters in the ground state are well consistent with the corresponding experimental values. The HOMO of 1 is dominantly localized on Ir atom and ppy ligand, but the HOMO of 2 and 3 have significant X ligand composition. Under the TD-DFT level with PCM model, the absorption and phosphorescence in CH2Cl2 media were calculated based on the optimized geometries in the ground and excited states, respectively. The lowest-lying absorption of 1 at 403 nm is attributed to {[dx2-y2(Ir)+dxy(Ir)+π(ppy)]→[π(ppy)]} transition with metal-to-ligand and intraligand charge transfer (MLCT/ILCT) transition characters, whereas those of 2 (449 nm) and 3 (475 nm) are related to {[dx2-y2(Ir)+dxy(Ir)+π(ppy)+π(NCS/NCO)]→[π(ppy)]} transition with MLCT/ILCT and ligand-to-ligand charge transfer (LLCT) transition characters. The phosphorescence of 1 at 466 nm can be described as originating from 3{[dx2-y2(Ir)+dxy(Ir)+π(ppy)][π(ppy)]} excited state, while those of 2 (487 nm) and 3 (516 nm) originate from 3{[dx2-y2(Ir)+dxy(Ir)+π(ppy)+π(NCS/NCO)][π(ppy)]} excited states. The calculated results showed that the transition character of the absorption and emission can be changed by adjusting the π electron-accepting abilities of the X ligands and the phosphorescent color can be tuned by altering the X ligands.  相似文献   
69.
基于乐观抱怨值和悲观抱怨值,通过建立二次规划模型求解(Hou,et al.,2018)定义的平衡博弈的最优妥协值,二次规划模型及求解方法比(Hou,et al.,2018)提出的字典序方法简单易操作.此外,文章进一步给出了同时满足个体合理性和群体有效性的乐观最优妥协值的求解算法.最后,通过数值实例说明文章建立的模型和方法的合理性和有效性.  相似文献   
70.
The AM1 semiempirical calculation method was employed to study the structures and electronic properties of a series of isoxazolo fullerene derivatives. Based on the AM1 geometry optimization, the electronic spectra of molecules were studied by using ZINDO/CIS methods. The results indicated the HOMO LUMO energy gaps of those isoxazolo fullerenes were lower than that of C60. There existed the intramolecular electron transfer from the additional section to C60 moiety. The electronic spectrum data showed that the exception of the absorption was beyond 400 nm.The results were in good accordance with the experiment results. Nonlinear optical susceptibilities α, β and γ of molecules were calculated according to Finite Field(FF)/AM1, and the influence of molecular structures on nonlinear optical properties was examined.  相似文献   
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