电荷转移对N,N-二甲基兰氨酸和朱洛利丁第一个超极化性的影响:基于DFT的比较研究
Usha Mandal1, Hasibul Beg2, Ajay Misra3
1Department of Chemistry, Vidyasagar University, Midnapore, 721101, India.
Journal of molecular modeling
|October 27, 2023
概括
这项研究研究了N,N-二甲基氨 (DMA) 和朱洛利丁 (JLD) 衍生物的非线性光学 (NLO) 特性. 由于增强的电荷分布,替代化合物表现出更高的NLO反应,在它们的最大吸收频率下具有最佳性能.
科学领域:
- 计算化学计算化学
- 材料科学 材料科学 材料科学
- 非线性光学是非线性光学.
背景情况:
- 研究了N,N-二甲基乙烯 (DMA) 和朱洛利丁 (JLD) 衍生物的第二阶非线性光学 (NLO) 反应.
- 检查了各种受体组 (X = -CF3, -CN, -NO2) 替换在DMA和JLD的平行位置上,它们充当捐赠者.
- 分析了电子相关性,频率分散和溶剂影响对NLO属性的影响.
研究的目的:
- 以计算方式检查DMA和JLD衍生品的第二阶非线性光学 (NLO) 响应,采用不同的受体替代.
- 为了将电子特征,电荷分布和兴奋状态参数与观察到的NLO参数 (βHRS) 相关联.
- 了解NLO反应的频率和溶剂极性依赖.
主要方法:
- 使用密度函数理论 (DFT) 进行量子力学计算.
- 使用CAM-B3LYP混合函数计算第一个超极化 (βHRS) 值.
- 在DFT/CAM-B3LYP/6-31G+(d,p) 理论层面进行计算.
主要成果:
- 与 -CF3 和 -CN 替代类似物相比,用 (-NO2) 替代的 DMA 和 JLD 呈现出明显更高的 NLO 反应 (βHRS).
- 与其他化合物相比,在-NO2替代化合物 (±443和±449) 中观察到更高的电荷分布.
- NLO反应 (βHRS) 与溶剂极性 (Kirkwood-Onsagar介电因子) 呈现线性关系,并且在每个化合物的 λmax.时达到顶峰.
结论:
- NLO反应受到接受组的性质的强烈影响,电子吸收强度发挥着关键作用.
- 电荷转移特性和电子特性对于确定这些捐赠-接受系统的NLO效率至关重要.
- 这些发现为设计具有增强非线性光学特性的分子提供了潜在应用的见解.
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