为了生成弱结的中型分子系统的潜在能量表面:氏-复合物的案例
Eya Derbali1, Yosra Ajili1, Bilel Mehnen2
1Laboratoire de Spectroscopie Atomique, Moléculaire et Applications LSAMA, Université de Tunis Al Manar, Tunis, Tunisia. yosra-aji@hotmail.fr.
Physical chemistry chemical physics : PCCP
|October 9, 2023
概括
准确的潜在能量表面 (PES) 对于理解分子相互作用至关重要. 本研究引入了对称性调整扰乱理论与密度功能理论 (SAPT(DFT)) 作为绘制复杂有机分子 PES 的有效方法,例如与相互作用的二.
科学领域:
- 计算化学计算化学
- 物理化学 物理化学
- 天体化学是天体化学.
背景情况:
- 显式相关联的合集群方法是准确的,但对于大分子来说,计算成本昂贵.
- 星际介质中的复杂有机分子 (COM) 需要精确的潜在能量表面 (PES) 来进行相互作用研究.
- 目前的方法在绘制大型系统的范德瓦尔斯复合体的多维PES (mD-PES) 方面遇到了困难.
研究的目的:
- 评估后哈特里-福克和对称性调整的扰动理论 (SAPT) 方法来生成mD-PESs.
- 确定与气体相互作用的COM的mD-PES映射的计算效率高和准确的方法.
- 为了生成一个3D-PES的酸-复合体,并将其应用于量子动态计算.
主要方法:
- 调查了MP2,可区分集群近似 (DCSD) 和它们明确相关的F12版本.
- 采用对称性调整的扰动理论与密度函数理论 (SAPT).
- 使用CCSD(T) -F12/aug-cc-pVTZ作为一个比较的基准.
主要成果:
- 发现MP2和DCSD方法不适合准确的PES生成.
- 明确相关的MP2-F12和DCSD-F12为准确的PES提供了更低的计算成本.
- SAPT ((DFT) 的表现与CCSD ((T) -F12/aug-cc-pVTZ的表现相当,因此它非常适合COMs.
- 用SAPT (DFT) 成功生成了氏-复合物的3D-PES.
结论:
- SAPT ((DFT) 是一种高效且计算可行的方法,用于绘制COMs的mD-PES.
- 生成的甲PES被用于量子动态计算.
- 这种方法可以准确地确定星际分子的旋转 (解刺激) 截面.
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