亚博-13-皇冠乙醇的光化学trans → cis和热 cis → trans异构化途径:对应力循环亚博系统的计算研究
Dilawar Singh Sisodiya1, Anjan Chattopadhyay1
1Department of Chemistry, Birla Institute of Technology and Science (BITS), Pilani, K. K. Birla Goa Campus, Zuarinagar, India.
The Journal of chemical physics
|July 17, 2024
概括
阿佐-13-皇冠乙烯的异体化受到其结构的阻碍,影响 cis 同体的形成. 这种阿佐冠衍生物显示出强大的Li+结合,表明了潜在的实际应用.
科学领域:
- 摄影化学的使用.
- 超分子化学 超分子化学
- 计算化学的计算化学
背景情况:
- 阿佐二烯衍生物以其光异构化特性而闻名.
- 皇冠乙烯是宏环化合物,在离子结合中具有应用.
- 亚博和皇冠的组合呈现出独特的光化学和结合特性.
研究的目的:
- 为了研究亚博-13-皇冠乙烯的光异构化机制.
- 为了比较其异构化行为与相关的阿佐烯系统.
- 为了探索亚博-13-皇冠以太的离子结合特性.
主要方法:
- 使用混合参考旋转翻转时间依赖密度函数理论 (MR-SF-TD-DFT) 的计算.
- 对光激发状态 (S1和S2) 潜在能量表面的分析.
- 热异构化路径和吉布斯自由活化能量的计算建模.
主要成果:
- 亚博-13-皇冠以太的跨异构体在S1表面呈现异构化障碍 (2.5-5.0kcal/mol),通过扭形形交叉导致cis异构体的形成.
- S2状态呈现旋转最小值,并经历内部转换,具有S2-S1特征的9kcal/mol的能量差距.
- 与二甲基替代类似物相比,阿佐-13-皇冠以太显示出更紧张的旋转路径,可能导致更低的trans → cis产量.
结论:
- 亚博-13-皇冠以太中的聚氧乙烯连接会影响其光异构化动态,产生障碍并影响异构体产量.
- 热 cis → trans 异构化具有 26 kcal/mol 的吉布斯自由活化能量.
- 转变异构体对Li+离子具有强烈的结合亲和力,这表明其在离子识别和传感方面的应用潜力.
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