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Updated: Jan 16, 2026

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常规和量子线性响应中的冗余参数依赖性以及单元参数化的波函数的运动方程理论
Erik Rosendahl Kjellgren1, Peter Reinholdt1, Karl Michael Ziems2,3
1Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark.
The Journal of chemical physics
|October 2, 2025
概括
使用线性响应 (LR) 理论计算分子激发能量可以产生轨道依赖的结果. 赫森矩阵的受约束的痕迹优化提高了LR计算的准确性,特别是对于较小的扩展.
科学领域:
- 量子化学 是一个量子化学.
- 计算化学计算化学
- 理论化学 理论化学
背景情况:
- 分子特性通常使用线性响应 (LR) 或运动方程 (EOM) 形式提取.
- 计算激发能量的轨道依赖性即使在准确的基本状态下也可能出现,如果LR膨胀被截断.
研究的目的:
- 通过LR理论计算的激发能量的轨道依赖性.
- 确定方法来提高LR计算的准确性,特别是对于截断的扩展.
主要方法:
- 对6-31G基数组中的 (He) 进行了计算,使用完整配置交互 (FCI) 基态.
- 测试了线性响应 (LR) 计算的各种参数化 (原始,预测,自相一致,状态转移).
- 为了减轻轨道依赖,采用了赫森矩阵的地面状态受约束的痕迹优化.
主要成果:
- 刺激能量被发现取决于当LR扩张被截断为单个时所选择的轨道,即使对于FCI基本状态.
- 这种轨道依赖性对于更复杂的系统以及单个和双重截断的LR扩张仍然存在.
- 对赫森矩阵的受约束的痕迹优化显著降低了观察到的轨道依赖.
结论:
- 轨道选择影响了激发能量的截止LR计算.
- 基态受约束轨迹优化是提高LR计算准确性的有效方法.
- 在受约束的轨迹优化中针对特定状态进一步细化了小LR扩展的光谱.
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