环辛四烯的芳香性与反芳香性  

Aromaticity and Antiaromaticity of Cyclooctetraene(C_(8)H_(8))

作　　者：程学礼[1] 赵燕云[1] 韩银锋[1] CHENG Xue-li;ZHAO Yan-yun;HAN Yin-feng(School of Chemistry and Chemical Engineering,Taishan University,Taian,Shandong 271021)

机构地区：[1]泰山学院化学化工学院,山东泰安271021

出　　处：《泰山学院学报》2024年第6期29-33,共5页Journal of Taishan University

基　　金：2024年度山东省教育规划重点课题“中学生创造性思维评价模型构建及监测研究”(2023ZD068);泰山学院2022年度教师教育研究专项课题“基于大概念下核心素养为导向的初中化学整体教学模式——项目式学习实践研究”(JY-01-202210)。

摘　　要：由于良好的稳定性和特殊的光、电、热和力学性质,含有共轭体系和离域π键的芳香性化合物广泛应用于光电功能材料、太阳能电池等领域,一直是化学家和物理学家研究的热点。在M06-2X-D3/def2-TZVP水平上研究了环辛四烯(C_(8)H_(8))的结构,用可视化方法展示了其非芳香性基态构型和三线态的芳香性。用LOL-π分析和轨道权重双描述符阐明,在基态C_(8)H_(8)的最稳定船式结构中,4个C=C双键是等同的,且亲核位点(4个C=C双键)和亲电位点(4个C-C单键)平均分布,为非芳香性结构;用约化密度梯度函数(RDG)揭示了船式构型稳定存在的原因;用自旋密度平面填色图和等值线图说明了三线态中单电子平均分散到8个C原子上。Due to their excellent stability and unique optical,electrical,thermal,and mechanical properties,aromatic compounds containing conjugated systems and delocalizedπbonds are widely used in fields such as optoelectronic functional materials and solar cells,and have always been a hot topic of research for chemists and physicists.The structures of cyclooctetraene(C_(8)H_(8))were investigated at M06-2X-D3/def2-TZVP level,and visualization methods were employed to reveal the most stable nonaromatic ground-state geometry.The localized orbital locator purely contributed byπelectrons(LOL-π)analysis and orbital-weighted dual descriptors were adopted to elucidate that,in the most stable ship-shaped C_(8)H_(8)configuration,the 4 C=C double bonds are equivalent,and the nucleophilic sites(4 C=C double bonds)and electrophilic sites(4 C-C single bonds)are distributed equally,so this D2d geometry is nonaromatic.The reduced density gradient(RDG)analysis was carried out to explain why the ship-shaped configuration is the most stable species.Then,the spin density color-filled plane map and contour map along with the isosurface map illustrate that the single electrons averagely disperse on the 8 C atoms in triplet C_(8)H_(8).

关 键 词：非芳香性 LOL-π分析 轨道权重双描述符 约化密度梯度函数 自旋密度 

分 类 号：O6[理学—化学] G64[文化科学—高等教育学]