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Updated: Sep 10, 2025

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将轨道优化密度函数理论扩展到L-Edge XPS及其他领域:通过非正交准退化扰动理论进行旋转-轨道合

Richard Kang^1,2, Leonardo A Cunha^1,2,3, Diptarka Hait^4,5,6,7

¹Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, United States.

Journal of chemical theory and computation

|August 26, 2025

概括

这项研究引入了一种新的量子力学方法,用于精确计算L边和更高的核心电子结合能 (CEBE),改进X射线光电子光谱 (XPS) 的解释. 这种增强的方法对第三排元素具有很高的准确性, 进步了计算化学.

科学领域:

计算化学
量子力学
光谱学

背景情况:

核心电子结合能 (CEBE) 对于解释X射线光电子光谱 (XPS) 是至关重要的.
轨道优化密度函数理论 (OO-DFT) 准确地预测K边缘CEBE,但在L边缘和更高的轨道合 (SOC) 方面存在困难.
对于内部外轨道的异于零角动量的元素,需要精确的CEBE计算.

研究的目的:

通过结合旋转轨道合 (SOC) 将OO-DFT的适用性扩展到L边和更高的边.
开发一种精确预测CEBE的计算方法,包括重元素的SOC效应.
为解释涉及L和更高边缘光谱的XPS数据提供更可靠的工具.

主要方法:

使用标量相对论,自旋受限制的开放OO-DFT来创建核心孔状态的基础.
使用非直角配置交互 (NOCI) 来计算全哈密尔顿式与SOC的矩阵元素.
使用选的1电子SOC运算符参数化了迪拉克-库伦-布莱特 (DCB) 哈密尔顿式.

主要成果:

这种称为NO-QDPT/SCAN的方法几乎与第三行元素的实验双重分割 (DS) 值达成了定量一致.
根据动态相关性进行校正并以SOC进行分割的计算CEBE显示了第三排原子的L边缘的高精度 (约0.2 eV).
第四行元素的精度下降,特别是从3d过渡金属系列的中间开始,原子数增加.

结论:

开发的NO-QDPT/SCAN方法与DCB选的1电子SOC操作器是计算L边缘CEBE的重要进展.
该方法为具有第三列原子的分子提供了准确的结果,增强了XPS数据的解释.
需要进一步开发方法,以提高第四行及更重元素的精度.

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