通过将Piris自然轨道函数与扩展随机阶段近似相结合,激发状态
Juan Felipe Huan Lew-Yee1,2, Iván Alejandro Bonfil-Rivera1, Mario Piris2,3,4
1Departamento de Física y Química Teórica, Facultad de Química, Universidad Nacional Autónoma de México, México City C.P. 04510, Mexico.
Journal of chemical theory and computation
|February 14, 2024
概括
本研究介绍了Piris自然轨道函数扩展随机相近似 (PNOF-ERPA) 方法,用于计算激发状态能量. 对于各种分子系统来说,PNOF-ERPA方法显示出有希望的准确性,特别是随着电子相关性的增加.
科学领域:
- 量子化学 是一个量子化学.
- 计算化学计算化学
- 理论化学 理论化学
背景情况:
- 计算激发状态能量对于理解分子特性和反应至关重要.
- 对于较大的系统,传统方法在计算上可能昂贵.
- 皮里斯自然轨道函数 (PNOF) 为电子结构计算提供了一个有前途的途径.
研究的目的:
- 开发和评估一种新的方法,PNOF-ERPA,用于计算激发状态能量.
- 评估不同PNOF变体 (PNOF5,PNOF7,GNOF) 与ERPA一起的性能.
- 调查电子相关性对兴奋状态能量计算的影响.
主要方法:
- 将从PNOF中重建的第二阶段减少密度矩阵与扩展随机相近似 (ERPA) 合起来.
- 实施和测试PNOF-ERPA,包括特定的变体PNOF-ERPA0,PNOF-ERPA1和PNOF-ERPA2.
- 将结果与已建立的配置交互 (CI) 方法进行比较以进行验证.
主要成果:
- 对于小分子 (H2,HeH+,LiH,Li2,N2) 的第一个激发状态,PNOF-ERPA方法表现出很好的准确性.
- 通过更高阶的ERPA近似来提高准确性 (ERPA0 < ERPA1 < ERPA2).
- 全球NOF (GNOF) 通过包括更多的电子相关性,为较大的系统提供了更好的结果,而PNOF5则对较小的系统有效.
结论:
- 通过PNOF-ERPA将PNOF扩展到激发状态计算是成功的.
- PNOF-ERPA提出了一种可行的和有前途的计算方法,用于激发状态化学的未来应用.
- 选择PNOF的功能对于准确性很重要,特别是在较大的分子中的电子相关性方面.
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