对于TDDFT近似辅助函数 (aas) 方法的能量和梯度的实施
Yuchen Wang1, Shana Havenridge1, Christine M Aikens1
1Department of Chemistry, Kansas State University, Manhattan, Kansas 66506, USA.
The Journal of chemical physics
|July 9, 2024
概括
我们通过简化计算开发了一个更快的近似时间依赖密度函数理论方法 (TDDFT-aas). 这种新方法准确地预测了纳米粒子光谱,并使分子的排放能量计算成为可能.
科学领域:
- 计算化学计算化学
- 量子化学 是一个量子化学.
- 材料科学 材料科学 材料科学
背景情况:
- 时间依赖密度函数理论 (TDDFT) 对于模拟兴奋状态属性至关重要.
- 在TDDFT中精确计算电子积分可能是计算上昂贵的.
- 像TDDFT+TB这样的现有方法依赖于特定的参数,限制了更广泛的适用性.
研究的目的:
- 实施和验证一种新的近似TDDFT方法,TDDFT-aas,以降低计算成本.
- 引入一种独立于紧密结合参数的新型合矩阵配方.
- 为了使分子发射能量的兴奋状态梯度的计算.
主要方法:
- 实施了时间依赖密度函数理论近似辅助s函数 (TDDFT-aas) 方法.
- 在K合矩阵中近似的双中心电子积分,以减少计算费用.
- 在合矩阵中使用了一个新的马函数,独立于紧密结合参数.
主要成果:
- TDDFT-aas与已建立的TDDFT和TDDFT+TB方法对银和金纳米粒子吸收光谱有很好的一致性.
- 该方法成功地降低了与精确的积分计算相比的计算成本.
- 对TDDFT-aas的分析兴奋状态梯度成功实现.
结论:
- TDDFT-aas为激发状态计算提供了一个计算效率高,准确的替代方案.
- 该方法独立于紧密结合参数,增强了其多功能性.
- 这项工作为使用近似的TDDFT方法计算分子排放能量铺平了道路.
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