对于时间依赖密度函数理论加密结合 (TDDFT + TB) 的分析兴奋状态梯度
Shana Havenridge1, Robert Rüger2, Christine M Aikens1
1Department of Chemistry, Kansas State University, Manhattan, Kansas 66502, USA.
The Journal of chemical physics
|June 8, 2023
概括
这项研究引入了一种更快的分析方法,使用时间依赖密度函数理论加紧结合 (TDDFT + TB) 来探索激发状态的潜在能量表面. 这加速了光发光材料的计算化学.
科学领域:
- 计算化学计算化学
- 量子力学就是量子力学.
- 材料科学 材料科学 材料科学
背景情况:
- 光发光机制对于各种应用至关重要,包括光催化,生物学和电子学.
- 分析激发状态潜在能量表面 (PESs) 使用传统方法,如时间依赖密度函数理论 (TDDFT),对于大型系统来说是计算密集的.
- 像TDDFT+TB这样的更快的近似方法可以高效地复制TDDFT结果,特别是对于大型纳米粒子.
研究的目的:
- 在TDDFT+TB框架内开发一种有效的分析方法来计算垂直激发能量的导数.
- 为了使光化学过程中激发状态潜在能量表面 (PESs) 的更有效的探索.
- 为研究大型系统的光发光特性提供一个计算上可行的方法.
主要方法:
- 使用Z-向量方法推导垂直激发能量的分析梯度.
- 使用辅助拉格朗来描述激发能量及其衍生物.
- 在将福克的导数,合和重叠矩阵纳入辅助拉格朗日数中后,解决拉格朗日乘数.
- 在阿姆斯特丹建模套件中实施该方法.
主要成果:
- 成功导出了TDDFT + TB中垂直激发能量的分析梯度.
- 通过分析辐射能量和优化激发状态几何学来证明该方法的概念证明.
- 实现了小型有机分子和贵金属纳米集群的高效激发状态PES探索.
结论:
- 在TDDFT + TB中开发的分析梯度为探索激发状态PES提供了一个计算效率高的替代方案.
- 与传统的TDDFT相比,这种方法在大型系统中显著加快了对光发光机制的研究.
- 该方法已在有机分子和纳米集群中得到验证,为光化学和材料科学中的更广泛应用铺平了道路.
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