在时间依赖密度函数理论中,振荡器强度和激发状态合用于双激发
Davood B Dar1, Neepa T Maitra1
1Department of Physics, Rutgers University, Newark, New Jersey 07102, USA.
The Journal of chemical physics
|December 1, 2023
概括
这项研究引入了时间依赖密度函数理论的新核心,以准确计算激发能量和振荡器强度,以挑战电子状态. 这一进步改善了分子性质和动态的模拟.
科学领域:
- 计算化学的计算化学
- 量子力学就是量子力学.
- 理论物理 理论物理
背景情况:
- 时间依赖密度函数理论 (TDDFT) 中的传统的亚亚巴特式近似通常无法捕获具有双激发特征的状态的激发能量.
- 现有的取决于频率的核,虽然可以改善激发能量的计算,但不能产生振荡器强度,这对于光谱特性和动力学至关重要.
研究的目的:
- 在TDDFT中开发一个修改后的非adiabatic内核,可以准确计算激发能量和振荡器强度.
- 为了解决描述复杂电子状态的先前方法的局限性.
主要方法:
- 对TDDFT进行修改的非adiabatic内核的导出.
- 在模型两电子系统 (原子) 上应用和验证新核.
- 在拉伸的几何形状下测试化 (LiH) 分子的激发状态过渡二极体上的核.
主要成果:
- 修改后的内核成功地计算了准确的激发能量和振荡器强度,用于以前通过adiabatic近似错过的状态.
- 与两种模型系统的传统近似相比,观察到显著的改进.
- 该方法在预测激发状态属性方面表现出增强的能力.
结论:
- 开发的非adiabatic内核提供了在TDDFT中电子激发的更完整的描述.
- 这一进步对于精确的线性吸收光谱,激发到激发状态合以及其他响应特性至关重要.
- 改进的方法为化学和物理学中的计算研究提供了更强大的工具.
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