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距离分离的局部混合函数与小的分数电荷和分数旋转错误:逃避DFT函数的零和游戏

Susanne Fürst¹, Martin Kaupp¹, Artur Wodyński¹

¹Institut für Chemie, Theoretische Chemie/Quantenchemie, Sekr. C7, Technische Universität Berlin, Straße des 17. Juni 135, D-10623 Berlin, Germany.

Journal of chemical theory and computation

|November 16, 2023

概括

新的范围分离局部混合函数 (scRSLHs) 纠正了强烈的相关性错误. 这些精确的方法可以改善复杂系统的计算,而无需显著的计算成本.

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.
密度函数理论密度函数理论

背景情况:

准确的电子结构计算对于理解分子和凝聚相系统至关重要.
现有的方法经常与强大的静态相关性和移位错误作斗争.
分离范围的局部混合物提供了一个有前途的框架,但需要进一步改进.

研究的目的:

开发和评估一系列新的强相关性纠正范围分离的局部杂交物种 (scRSLHs).
为了提高密度函数理论 (DFT) 的准确性,用于具有强大的静态相关性和移位错误的系统.
为复杂的分子和凝聚相系统创建计算高效的函数.

主要方法:

将现有的强相关性 (sc) 纠正扩展到 ωLH22t 分隔范围的局部混合体.
在强烈相关的区域实施位置依赖的精确交换添加剂的减少.
应用缓冲程序和对局部混合功能的额外校正.

主要成果:

scRSLH保留了弱相关系系统和准粒子能量的 ωLH22t 的性能.
在像拉伸债券这样的情况中,大幅减少静态相关性错误.
由于减少了移位错误,改善了热化学和运动参数.
像 ωLH23tdE 和 ωLH23tdP 这样的函数对复杂系统有很大的前景.
最小化了分数电荷和分数旋转的错误,避免了通常的权衡.

结论:

开发的scRSLH为具有挑战性的系统提供了DFT精度的显著提升.
这些函数在精度和计算成本之间提供了有利的平衡.
预计scRSLHs将在准确的Kohn-Sham DFT计算中实现新的边界.

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