Besalú-Sala Pau, Bruneval Fabien, Pérez-Jiménez Ángel José, Sancho-García Juan Carlos, Rodríguez-Mayorga Mauricio
Department of Chemistry and Pharmaceutical Sciences, Amsterdam Institute for Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, De Boelelaan 1083, HV Amsterdam 1081, The Netherlands.
Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona, Girona 17003, Spain.
J Chem Theory Comput. 2023 Sep 26;19(18):6062-6069. doi: 10.1021/acs.jctc.3c00674. Epub 2023 Sep 11.
The accurate computation of static nonlinear optical properties (SNLOPs) in large polymers requires accounting for electronic correlation effects with a reasonable computational cost. The Random Phase Approximation (RPA) used in the adiabatic connection fluctuation theorem is known to be a reliable and cost-effective method to render electronic correlation effects when combined with density-fitting techniques and integration over imaginary frequencies. We explore the ability of the RPA energy expression to predict SNLOPs by evaluating RPA electronic energies in the presence of finite electric fields to obtain (using the finite difference method) static polarizabilities and hyperpolarizabilities. We show that the RPA based on hybrid functional self-consistent field calculations yields accurate SNLOPs as the best-tuned double-hybrid functionals developed today, with the additional advantage that the RPA avoids any system-specific adjustment.
在大型聚合物中精确计算静态非线性光学性质（SNLOPs）需要以合理的计算成本考虑电子相关效应。绝热连接涨落定理中使用的随机相位近似（RPA），当与密度拟合技术和对虚频率进行积分相结合时，已知是一种可靠且具有成本效益的方法来呈现电子相关效应。我们通过在有限电场存在的情况下评估RPA电子能量以获得（使用有限差分法）静态极化率和超极化率，来探索RPA能量表达式预测SNLOPs的能力。我们表明，基于杂化泛函自洽场计算的RPA产生的SNLOPs与当今开发的最佳调谐双杂化泛函一样准确，另外一个优点是RPA避免了任何特定于系统的调整。
