在密度校正密度函数理论的框架内,简单而有效的途径,以改善能量学
1Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom.
Journal of chemical theory and computation
|August 1, 2023
概括
我们开发了一种新的动能指标,以有效地确定何时在密度校正 (DC(HF) -DFT) 计算中使用哈特里-福克 (HF) 密度. 这种方法还允许纠正密度函数本身,创建纠正的 (C(HF) -DFT).
科学领域:
- 量子化学 是一个量子化学.
- 计算材料科学科学 计算材料科学
- 理论物理 理论物理
背景情况:
- 密度校正的哈特里-福克密度函数理论 (DC(HF) -DFT) 需要从密度函数中识别错误的密度.
- 精确的电子密度对于可靠的电子结构计算至关重要.
研究的目的:
- 引入一种新型指标,可靠地检测何时哈特里-福克 (HF) 密度高于密度函数理论 (DFT) 密度.
- 开发一种高效的程序来纠正DC(HF) -DFT计算中的电子密度和功能.
主要方法:
- 提出了基于DFT和HF计算之间的非相互作用动能差异的新指标.
- 该指标直接将自相一致的DFT密度与HF密度进行比较.
- 引入了评估相关混合函数的程序,以纠正函数与密度一起.
主要成果:
- 动能指标是大小密集的,可靠的,高效的.
- 拟议的指标准确地确定了使用高频密度的必要性.
- 在C(HF) -DFT程序纠正密度和功能.
结论:
- 开发的动能指标提供了一种有效和可靠的方法来改进DC (HF) -DFT.
- 在C ((HF) -DFT程序提供了更全面的校正通过提炼密度和功能,提高电子结构预测的准确性.
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