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使用与格拉斯曼尼人一起使用受限制的开放方法绘制无旋转污染的潜在能量表面

Jake A Tan¹, Ka Un Lao²

¹Department of Chemistry, Gottwald Center for the Sciences, University of Richmond, Richmond, VA, USA. jake.tan@richmond.edu.

Physical chemistry chemical physics : PCCP

|December 19, 2023

概括

基于拉格朗奇的扩展格拉斯曼插值 (G-Int) 方法准确地构建了开系统的潜在能量表面. 这种强大的方法为自相一致的场计算提供了优异的初始猜测,确保了无旋转污染的结果.

科学领域:

计算化学的计算化学
量子化学是一个量子化学.
理论化学理论化学

背景情况:

准确的潜在能量表面 (PES) 对于理解化学反应和分子性质至关重要.
传统的用于构建开放系统的 PES 的方法经常面临准确性和计算效率方面的挑战.
开发可靠的初始猜测方案用于自相一致场 (SCF) 计算对于开放系统至关重要.

研究的目的:

扩展基于拉格朗的格拉斯曼插值 (G-Int) 方法,用于使用受限制的开 (RO) 方法的开系统.
评估扩展的G-Int方法在构建准确的PES时的性能.
评估G-Int方法作为SCF计算的初始猜测方案的有效性.

主要方法:

扩展基于拉格朗的格拉斯曼插值 (G-Int) 方法用于开系统.
应用G-Int来构建瓦纳 (II) 氧化物,基和甲硫基化物基离子的PES.
将G-Int生成的密度矩阵与传统的SCF初始猜测方案 (SADMO,GWH,CORE) 的比较.
调查网格采样策略 (均距与不均距) 以减轻朗奇现象.

主要成果:

通过G-Int方法,成功地为研究的开放系统构建了准确的PES.
与传统方案相比,G-Int的密度矩阵显著改善了SCF的融合和准确性.
G-Int 能量满足了变量原理,并且优于基于直接能量的插值.
基于缩放的高斯-切比舍夫方程的不均间隔的网格采样有效地解决了由朗格现象引起的振荡.

结论:

扩展的G-Int方法是一种高效和强大的策略,用于为开系统构建无旋转污染的PES.
G-Int为SCF计算提供了卓越的初始猜测,提高了准确性和趋同.
将G-Int与适当的网格采样技术相结合,为准确的PES构建提供了一种通用方法.

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