高精度和强大的基于约束的轨道优化的核心激发
Yannick Lemke1, Jörg Kussmann1, Christian Ochsenfeld1,2
1Chair of Theoretical Chemistry, Department of Chemistry, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, Munich D-81377, Germany.
The journal of physical chemistry. A
|November 4, 2024
概括
我们适应了基于约束的轨道优化激发状态方法 (COOX) 进行核心激发. 这种方法准确地预测了X射线吸收光谱,性能优于现有的方法.
科学领域:
- 计算化学计算化学
- 量子化学 是一个量子化学.
- 频谱学是一种光谱学.
背景情况:
- 核心激发,如K和L边缘,对于理解材料特性和化学过程至关重要.
- 传统的方法,如线性响应时间依赖的DFT (LR-TDDFT),在准确计算核心激发能量方面面临挑战.
- 基于约束的轨道优化激发状态方法 (COOX) 已经显示出对价值激发的承诺.
研究的目的:
- 适应和验证COOX方法用于准确计算核心级电子激发.
- 将COOX的适用性扩展到各种元素的K,L和M边缘激发.
- 为了比较适应的COOX方法的性能与已建立的技术,如 ΔSCF 方法.
主要方法:
- 开发一种COOX方法的旋转不受限制的变体,以处理核心激发.
- 整合了三重净化方案和受约束的不受限制的哈特里-福克形式主义.
- 包括标量相对论纠正和半经验旋转轨道合处理.
主要成果:
- 适应的COOX方法在第二和第三周期原子的K和L边缘激发中实现了亚电子电压的准确性.
- 该方法证明了对包括在内的较重元素的L和M边缘激发的计算可行性和数值稳定性.
- COOX 显示了与 ΔSCF 方法相当或优于该方法的性能,并且具有更好的收性质.
结论:
- 旋转不受限制的COOX方法是模拟核心激发的可靠和高效工具.
- COOX提供了一个有前途的替代方案,可以准确和经济有效地预测X射线吸收光谱.
- 这一进步有助于更深入地了解通过X射线光谱检测到的电子结构和化学动态.
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