电子光谱中振荡器强度的理论与实验相比如何? 提出范围分离的混合动力,可靠的问责制
Mahdi Soltani Nejad1, Mojtaba Alipour1
1Department of Chemistry, School of Science, Shiraz University, Shiraz 71946-84795, Iran. malipour@shirazu.ac.ir.
Physical chemistry chemical physics : PCCP
|December 13, 2023
概括
准确计算电子光谱的振荡器强度是一个挑战. 这项研究引入了与溶解模型相结合的最佳调范围分离混合体 (OT-RSH),为预测光谱强度提供了可靠且负担得起的替代方案.
科学领域:
- 原子和分子光谱学 原子和分子光谱学
- 计算化学的计算化学
- 理论化学 理论化学
背景情况:
- 振荡器强度对于理解原子和分子光谱学至关重要,它与光谱峰值强度直接相关.
- 准确计算振荡器强度在理论和实验方法中仍然是一个重大挑战.
- 对于振荡器强度的现有理论治疗方法是有限的,并且在计算上很苛刻.
研究的目的:
- 用先进的计算方法研究有机化合物的电子光谱中的振荡器强度.
- 开发和评估新的理论方法,可靠地预测振荡器强度.
- 确定理论参数的最佳组合,以准确计算振荡器强度.
主要方法:
- 使用最佳调的范围分离混合动力 (OT-RSHs) 与极化连续模型 (PCM) 相结合.
- 引入了选版本 (OT-SRSHs-PCM),以考虑电子相关性选效应.
- 检查了密度函数近似,Hartree-Fock交换和范围分离参数的影响.
主要成果:
- 为了准确预测振荡器强度,需要在方法参数之间做出特定的妥协.
- 基于概括梯度近似的优化OT-RSHs-PCM方法显示出卓越的性能.
- 最好的近似准确地预测了开发集中不包括的化合物的振荡器强度.
结论:
- 拟议的OT-RSHs-PCM和OT-SRSHs-PCM方法可提供可靠的振荡器强度预测.
- 开发的方法提供了一个负担得起的替代方案,以计算昂贵的基于波函数的方法.
- 这项工作促进了电子光谱学中的理论建模和实验验证.
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