A theoretical study on the relationship between the excited states and the photochemical behavior of stilbene and its derivatives

二苯乙烯及其衍生物激发态与光化学行为关系的理论研究

• 批准号: 12640485
• 负责人: AMATATSU Yoshiaki
• 金额: $ 1.98万
• 依托单位: Akita University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12640485/
• 关键词: Abinitio MO method; stilbene; stilbenoids; styrene; 4-dimethylamino, 4'-cyanostilbene; excited states; dynamics; 4-ジメチルアミノ,4'-シアノスチルベン

The photochemical behavior of stilbene and its derivatives has been of great interest in photochemistry. In spite of much effort to elucidate it both experimentally and theoretically, there is no widely accepted picture. In this research project, we examined the electronic structures and dynamics in the excited states of stilbene and its derivatives (stilbenoids) by means of ab initio molecular orbital (MO) method. We reduced the computational labor of complete. active space self-consistent field calculations based on preliminary configuration interaction calculations.1) the photochemical behavior of stilbene in the Franck-Condon (FC) region of teans-stilbeneWe calculated the potential energy surfaces in the FC region to know the initial process of trans-stilbene. Right after electronic excitation of S_0-S_3 which is main transition in the first excited manifold, a planar delocalized quinoid structure is preferable so as for the photoisomerization to take place.2) the photochemical behavior of stvreneWe globally scanned the potential energy surfaces of styrene including the important ingredients of the S_1/S_0- and S_2/S_1-conical intersections (CIXs) so as to present a new and reasonable picture of the photochemistry of styrene.3)the S_1/S_0-CIX_s of styrene derivativesWe calculated the S_1/S_0-CIX_s of styrene derivatives. It is found that they are characterized by a crossing region between zwitterionic and covalent diradical states.4) the photochemical behavior of 4-dimethylamino. 4'-cyanostilbene (DCS)We calculated the free energy surface of DCS in polar solvent to discuss the formation mechanism of the twisted internal charge transfer state. We also calculated the S_1/S_0-CIX for the photosiomerization.

二苯乙烯及其衍生物的光化学行为一直是光化学研究的热点。尽管从实验和理论上都做出了很多努力来阐明这一点，但还没有一个被广泛接受的图景。在本研究项目中，我们用从头算分子轨道(MO)方法研究了二苯乙烯及其衍生物(二苯乙烯类)激发态的电子结构和动力学。我们减少了Complete的计算量。基于初步组态相互作用计算的活性空间自洽场计算1)二苯乙烯在二苯乙烯的弗兰克-康登(FC)区的光化学行为我们计算了FC区的势能面，以了解反式二苯乙烯的初始过程。在第一激发流形的主要跃迁S_0-S_3的电子激发后，最好是平面离域的奎宁结构，以便发生光异构化。2)苯乙烯的光化学行为我们全局扫描了包括重要组分S_1/S_0-和S_2/S_1的势能面，从而呈现出一幅新的合理的苯乙烯光化学图。3)苯乙烯衍生物的S_1/S_0-CIX_S计算了苯乙烯衍生物的S_1/S_0-CIX_S。研究发现，它们的特征是在两性离子和共价双自由基态之间存在一个交叉区。4)4-二甲氨基的光化学行为。4‘-氰基二苯乙烯(DC)在极性溶剂中的自由能面的计算，讨论了扭曲内电荷转移态的形成机理。我们还计算了S_1/S_0-CIX的光化异构化反应。

项目成果

Y. Amatatsu: "Ab initio study on the photochemical behavior of 4-dimethylamino, 4' -cyanostilbene"Chem. Phys.. 274. 87-98 (2001)

Y. Amatatsu：“从头开始研究 4-二甲氨基，4-氰基芪的光化学行为”Chem。

D.Xie: "Three-dimensional Photodissociation Dynamics of Rotational State Selected Methyl Iodide"Journal of Physical Chemistry A. 104. 1009-1019 (2000)

谢东：“旋转态选择碘甲烷的三维光解离动力学”物理化学学报A. 104. 1009-1019 (2000)

Y.Amatatsu: "Ab initio study on the photochemical behavior of styrene"Journal of Computational Chemistry. (印刷中). (2002)

Y.Amatatsu：“苯乙烯光化学行为的从头研究”计算化学杂志（2002 年出版）。

Y. Amatatsu: "Ab initio study on the electronic structures of styrene in the Franck-Condon region"J. Compt. Chem.. (in press).

Y. Amatatsu：“从头开始研究 Franck-Condon 区域苯乙烯的电子结构”J.

Y.Amatatsu: "Ab initio study on the photochemical behavior of 4-dimethylamino, 4'-cyanostilbene"Chemical Physics. 274. 87-98 (2001)

Y.Amatatsu：“从头开始研究 4-二甲氨基、4-氰基芪的光化学行为”化学物理。