Bednarska Joanna, Zaleśny Robert, Bartkowiak Wojciech, Ośmiałowski Borys, Medved' Miroslav, Jacquemin Denis
Department of Physical and Quantum Chemistry, Faculty of Chemistry, Wrocław University of Science and Technology , Wyb. Wyspiańskiego 27, PL-50370 Wrocław, Poland.
Faculty of Chemical Technology and Engineering, UTP University of Science and Technology , Seminaryjna 3, PL-85326 Bydgoszcz, Poland.
J Chem Theory Comput. 2017 Sep 12;13(9):4347-4356. doi: 10.1021/acs.jctc.7b00469. Epub 2017 Aug 24.
This article aims at a quantitative assessment of the performances of a panel of exchange-correlation functionals, including semilocal (BLYP and PBE), global hybrids (B3LYP, PBE0, M06, BHandHLYP, M06-2X, and M06-HF), and range-separated hybrids (CAM-B3LYP, LC-ωPBE, LC-BLYP, ωB97X, and ωB97X-D), in predicting the vibrationally resolved absorption spectra of BF-carrying compounds. To this end, for 19 difluoroborates as examples, we use, as a metric, the vibrational reorganization energy (λ) that can be determined based on the computationally efficient linear coupling model (a.k.a. vertical gradient method). The reference values of λ were determined by employing the CC2 method combined with the cc-pVTZ basis set for a representative subset of molecules. To validate the performances of CC2, comparisons with experimental data have been carried out as well. This study shows that the vibrational reorganization energy, involving Huang-Rhys factors and normal-mode frequencies, can indeed be used to quantify the reliability of functionals in the calculations of the vibrational fine structure of absorption bands, i.e., an accurate prediction of the vibrational reorganization energy leads to absorption band shapes better fitting the selected reference. The CAM-B3LYP, M06-2X, ωB97X-D, ωB97X, and BHandHLYP functionals all deliver vibrational reorganization energies with absolute relative errors smaller than 20% compared to CC2, whereas 10% accuracy can be achieved with the first three functionals. Indeed, the set of examined exchange-correlation functionals can be divided into three groups: (i) BLYP, B3LYP, PBE, PBE0, and M06 yield inaccurate band shapes (λ < λ), (ii) BHandHLYP, CAM-B3LYP, M06-2X, ωB97X, and ωB97X-D provide accurate band shapes (λ ≈ λ), and (iii) LC-ωPBE, LC-BLYP, and M06-HF deliver rather poor band topologies (λ > λ). This study also demonstrates that λ can be reliably estimated using the CC2 model and the relatively small cc-pVDZ basis set. Therefore, the linear coupling model combined with the CC2/cc-pVDZ level of theory can be used as a very efficient approach to determine λ values that can be used to select the most adequate functional for more accurate vibronic calculations, e.g., including more refined models and environmental effects.
本文旨在对一组交换关联泛函的性能进行定量评估，这些泛函包括半局域泛函（BLYP和PBE）、全局杂化泛函（B3LYP、PBE0、M06、BHandHLYP、M06 - 2X和M06 - HF）以及范围分离杂化泛函（CAM - B3LYP、LC - ωPBE、LC - BLYP、ωB97X和ωB97X - D），用于预测含BF化合物的振动分辨吸收光谱。为此，以19种二氟硼酸盐为例，我们使用基于计算效率高的线性耦合模型（又称垂直梯度法）确定的振动重组能（λ）作为衡量标准。λ的参考值通过将CC2方法与cc - pVTZ基组结合用于分子的代表性子集来确定。为了验证CC2的性能，也已与实验数据进行了比较。本研究表明，涉及黄 - 里斯因子和简正模式频率的振动重组能确实可用于量化泛函在吸收带振动精细结构计算中的可靠性，即准确预测振动重组能会使吸收带形状更符合所选参考。与CC2相比，CAM - B3LYP、M06 - 2X、ωB97X - D、ωB97X和BHandHLYP泛函给出的振动重组能的绝对相对误差均小于20%，而前三种泛函可实现10%的精度。实际上，所研究的交换关联泛函集可分为三组：（i）BLYP、B3LYP、PBE、PBE0和M06给出的带形状不准确（λ < λ），（ii）BHandHLYP、CAM - B3LYP、M06 - 2X、ωB97X和ωB97X - D提供准确的带形状（λ ≈ λ），（iii）LC - ωPBE、LC - BLYP和M06 - HF给出的带拓扑相当差（λ > λ）。本研究还表明，使用CC2模型和相对较小的cc - pVDZ基组可以可靠地估计λ。因此，线性耦合模型与CC2/cc - pVDZ理论水平相结合可作为一种非常有效的方法来确定λ值，该值可用于选择最适合的泛函以进行更精确的振动电子计算，例如包括更精细的模型和环境效应。
