对BIPS螺旋的TD-DFT研究:功能和高极性溶剂对C的作用
Ivan N Dobrovolskiy1, Victor V Kostjukov1
1Physics Department, Sevastopol State University, Sevastopol, Ukraine.
Journal of computational chemistry
|June 9, 2023
概括
这项研究从理论上分析了甲醇中的BIPS光化学循环. 它发现特定的混合函数准确地预测S0 → S1过渡和Cspiro-O键的减弱,这对于理解螺旋的行为至关重要.
科学领域:
- 计算化学计算化学
- 摄影化学的使用.
- 量子力学就是量子力学.
背景情况:
- BIPS的光化学循环 (1',3'-二-1',3',3'-三甲基-6-化[2H-1-二-2,2'-[2H]印]) 是复杂的,需要精确的理论建模.
- 了解这个周期中的电子转换和键动态对于设计光色材料至关重要.
- 以前的研究已经探索了BIPS光化学,但极性溶剂和特定计算方法的影响需要进一步澄清.
研究的目的:
- 用一套全面的混合功能来理论分析BIPS光化学循环.
- 调查极极化溶剂 (甲醇) 对BIPS光化学转换的显著影响.
- 确定最适合的计算函数来准确建模BIPS光化学循环,特别是Cspiro-O键裂变.
主要方法:
- 使用40个混合密度函数进行了BIPS光化学循环的理论分析.
- 在计算中纳入了极性强溶剂 (甲醇) 的作用.
- 分析了电子过渡 (S0 → S1,S0 → S2),Cspiro-O键的增强/减弱,振荡器的强度和结构的扭曲.
主要成果:
- 具有中高哈特里-福克交换率 (%HF) 的函数准确预测了主导的S0 → S1过渡和Cspiro-O债券减弱,与实验数据保持一致.
- 极性溶剂甲醇显著影响了光化学循环,减少了预测Cspiro-O键解离的功能数量,并增加了振荡器强度.
- 甲醇和BIPS之间的键改变了主导过渡,并进一步降低了特定函数的Cspiro-O键解离 (M052X,CAM-B3LYP).
结论:
- 建议使用M052X和CAM-B3LYP函数来建模BIPS光化学循环,因为它们可以准确地预测主导的HOMO-1 → LUMO配置.
- 该研究量化描述了电子密度的再分配,并确定了在循环期间驱动Cspiro和氧原子接近的静电机制.
- 极地溶剂效应和键在螺旋的光化学中起着至关重要的作用,影响电子过渡和键动态.
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