在密度函数理论中,激发状态的直接无约束优化
Hanh D M Pham1, Rustam Z Khaliullin1
1Department of Chemistry, McGill University, 801 Sherbrooke St West, Montreal, Québec H3A 0B8, Canada.
Journal of chemical theory and computation
|April 2, 2025
概括
一种新的方法,变量度量时间独立的DFT (VM TIDFT),可以实现精确的兴奋状态优化. 这种方法克服了变量崩,改善了对具有挑战性的电子状态的计算.
科学领域:
- 量子化学 是一个量子化学.
- 计算化学的计算化学
- 理论化学 理论化学
背景情况:
- 轨道优化密度函数理论 (DFT) 为激发状态提供了取决于时间的 (TD) DFT的替代方案.
- TDDFT与涉及显著电子密度再分配的兴奋状态作斗争,如电荷转移和双电子激发.
研究的目的:
- 开发一种简单而强大的激发状态优化方法.
- 为了解决与兴奋状态计算固有的变化崩问题.
- 为了提高计算具有挑战性的兴奋状态的准确性.
主要方法:
- 引入了变量度量时间独立的DFT (VM TIDFT).
- 在优化过程中允许非对角电子状态,逐渐强制执行对角性,并具有惩罚函数.
- 利用分子轨道系数作为封闭形式梯度的独立变量.
主要成果:
- VM TIDFT成功克服了变化崩.
- 该方法在各种分子系统的数值测试中证明了它的稳定性和准确性.
- 准确的能量得到了标准和具有挑战性的激发 (电荷转移,双电子).
结论:
- VM TIDFT 提供了一种可靠的激发状态优化方法.
- 这种方法扩展了DFT用于描述复杂电子激发的功能.
- VM TIDFT 是 TDDFT 的一个有希望的替代方案,用于挑战激发状态问题.
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