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为了更好地使SCF-RDMFT程序趋同,利用黑森币

Nicolas G Cartier¹, Klaas J H Giesbertz¹

¹Department of Chemistry & Pharmaceutical Sciences and Amsterdam Institute of Molecular and Life Sciences (AIMMS), Faculty of Science, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands.

Journal of chemical theory and computation

|April 26, 2024

概括

一体减少密度矩阵函数理论为处理静态相关性提供了计算优势. 这项研究引入了一种改进的优化方法,使用Hessian加速融合,显著降低计算成本.

科学领域:

计算化学是一种计算化学.
量子化学是一种量子化学.
材料科学是一种材料科学.

背景情况:

一体减少密度矩阵函数理论 (1-RDMFT) 是密度函数理论 (DFT) 的替代方案.
1-RDMFT可以处理静态关联效应,这对许多化学系统至关重要.
1-RDMFT的一个主要缺点是其自相一致的能量优化的缓慢融合.

研究的目的:

在1-RDMFT中加速缓慢的自我一致的能量优化.
为了降低与1-RDMFT计算相关的计算成本.
为了提高1-RDMFT在电子结构计算中的实际应用性.

主要方法:

利用能源的赫西安,包括合术语,以增强优化趋同.
调查精确的Hessian在减少代数量的有效性.
使用廉价的精确元件与布罗伊登弗莱切尔戈德法尔布沙诺 (BFGS) 更新相结合,为赫西安人开发了一个实用的近似值.

主要成果:

精确的Hessian显著减少了自我一致的融合所需的代数.
提出的赫塞纳近似在实践中被证明是有效的.
新方法大大提高了1-RDMFT计算的效率.

结论:

使用基于赫森的方法,特别是近似方法,可以克服1-RDMFT.中的缓慢融合问题.
本文介绍了一种计算可行的方法来加速1-RDMFT,使其更适用于复杂的系统.
开发的方法为更高效的电子结构和材料科学研究提供了一个有希望的途径.

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