扩展配置-相互作用单一方法与核心/值分离 (XCIS-CVS):开放分子的核心层次光谱
Avik Kumar Ojha1, John M Herbert1
1Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States.
Journal of chemical theory and computation
|November 19, 2025
概括
扩展的配置-相互作用单元 (XCIS) 与核心/分离 (CVS) 准确地模拟开分子中的激发状态. 这种方法克服了旋转污染问题,提供了与实验X射线过渡数据的半定量一致.
科学领域:
- 量子化学 是一个量子化学.
- 计算光谱学是一种计算光谱学.
- 电子结构理论 电子结构理论
背景情况:
- 核到价值转换探测价值虚拟轨道,对于具有退化的边界轨道的开放系统至关重要.
- 像时间依赖密度函数理论这样的标准方法在开激发状态计算中与旋转污染作斗争.
- 基于Hartree-Fock的受限开配置交互单元 (ROHF-CIS) 由于旋转污染,通常会产生不准确的结果.
研究的目的:
- 实施和应用扩展配置-交互单元 (XCIS) 方法与核心/值分离 (CVS) 近似.
- 准确地建模开放分子中的纯自旋激发状态和核心到值转换.
- 评估XCIS-CVS用于模拟3D过渡金属复合体中的X射线过渡的性能.
主要方法:
- 扩展配置-交互单元 (XCIS) 波函数替代品的实施.
- 纳入核心/值分离 (CVS) 近似值,以关注相关轨道.
- 在各种开放系统中模拟K边和前边X射线过渡的应用.
主要成果:
- XCIS方法有效地消除了在ROHF-CIS计算中存在的旋转污染.
- 与标准CIS方法相比,XCIS-CVS为激发状态提供了更高的准确性.
- 对3D过渡金属复合物的模拟K边缘和前边缘轨道分裂显示了与实验数据的半定量一致.
结论:
- XCIS-CVS是一种强大而准确的方法,用于研究开系统中的激发状态和光谱过渡.
- 该方法成功地解决了单刺激理论对具有挑战性的开分子的局限性.
- XCIS-CVS提供了一种可靠的计算工具,用于解释过渡金属复合物的X射线光谱.
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