极化一致的介电选在极化连续模型中计算了溶解能量的极化
Roshan Khatri1, Barry D Dunietz1
1Kent State University, Department of Chemistry and Biochemistry, Kent, Ohio 44242, USA.
The Journal of chemical physics
|August 18, 2023
概括
一个新的计算框架在极化连续模型 (PCM) 计算中一致应用介电选. 这种方法提高了溶解能预测的准确性,特别是密度函数理论 (DFT) 方法.
科学领域:
- 计算化学计算化学
- 理论化学 理论化学
- 物理化学 物理化学
背景情况:
- 精确计算溶解能量对于理解溶液中的化学过程至关重要.
- 现有的极化连续模型 (PCM) 方法可能在介电选中表现出不一致.
- 密度函数理论 (DFT) 与PCM相结合,有时会高估溶解能.
研究的目的:
- 开发和验证一个极化一致的计算框架,用于溶解能量计算.
- 调查一致的介电选对电子结构和溶解能量的影响.
- 为了提高DFT-PCM方法的预测准确度.
主要方法:
- 在PCM框架 (SRSH-PCM) 中实施选范围分离混合 (SRSH) 功能.
- 在PCM自相一致反应场 (SCRF) 代和电子结构哈密尔顿式中,对介电选的一致施加.
- 分析Hartree-Fock (HF) 和DFT计算,使用选方法和未选方法.
主要成果:
- 选的HF-PCM计算正确地复制了轨道能量差距与介电常数的线性依赖.
- 未选的HF-PCM计算显示不准确,近乎恒定的轨道能量,与电离能差距不一致.
- 与未经选的方法相比,介电选的计算产生较小的溶解能.
- SRSH-PCM方法减少了DFT-PCM对溶解能量的过高估计,特别是在更高的介电常数和极性溶液中.
结论:
- 在计算框架中,一致的介电选对于准确的电子结构和溶解能计算至关重要.
- SRSH-PCM方法提供了更可靠的溶解能量的描述,减轻了DFT-PCM的高估.
- 这项工作有助于开发可预测的,无参数的求解模型.
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