Benchmarking Semiempirical QM Methods for Calculating the Dipole Moment of Organic Molecules
Benchmarking Semiempirical QM Methods for Calculating the Dipole Moment of Organic Molecules
复制标题
用于计算有机分子偶极矩的半经验 QM 方法的基准测试
DOI：
10.1021/acs.jpca.1c10144
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发表时间：
2022
期刊：
影响因子：
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通讯作者：
Szilvási, Tibor
中科院分区：
文献类型：
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作者：
Soyemi, Ademola;Szilvási, Tibor
偶极矩是电荷分布和极性的简单描述符，对于理解和预测各种分子特性非常重要。半经验 (SE) 方法提供了一种经济有效的方法来计算偶极矩，可用于高通量筛选应用，尽管该方法的准确性仍存在疑问。因此，我们评估了涵盖各种 SE 近似的 AM1、GFN0-xTB、GFN1-xTB、GFN2-xTB、PM3、PM6、PM7、B97-3c、HF-3c 和 PBEh-3c SE 方法，以直接评估 SE 方法在使用 QM7b 数据库中包含的 7211 个有机分子预测分子偶极矩及其方向方面的性能。我们发现 B97-3c 和 PBEh-3c 相对于耦合簇参考值表现最佳，产生偶极矩，平均绝对误差 (MAE) 分别为 0.10 和 0.11 D，这与之前报道的密度泛函理论 (DFT) 方法 (∼0.1 D) 的 MAE 类似。原子组成分析表明，所有 SE 方法对碳氢化合物都表现出良好的性能，误差范围在参考数据的 1 D 以内，而对含硫化合物的性能最差，只有 B97-3c 和 PBEh-3c 表现出可接受的性能。我们还评估了 SE 优化几何结构（而不是基准 DFT 几何结构）的效果，这表明 AM1 和 PM3 的性能急剧下降，误差范围增加了两倍。根据我们的总体发现，我们强调，使用 GFN2-xTB（MAE：0.25 D）在准确性和计算成本之间存在最佳折衷，比 B97-3c 和 PBEh-3c 快 3 个数量级。因此，我们建议使用 GFN2-xTB 来经济有效地计算含有 C、H、O 和 N 原子的有机分子的偶极矩，而对于含硫有机分子，我们建议使用 PBEh-3c。
The dipole moment is a simple descriptor of the charge distribution and polarity and is important for understanding and predicting various molecular properties. Semiempirical (SE) methods offer a cost-effective way to calculate dipole moment that can be used in high-throughput screening applications although the accuracy of the methods is still in question. Therefore, we have evaluated AM1, GFN0-xTB, GFN1-xTB, GFN2-xTB, PM3, PM6, PM7, B97-3c, HF-3c, and PBEh-3c SE methods, which cover a variety of SE approximations, to directly assess the performance of SE methods in predicting molecular dipole moments and their directions using 7211 organic molecules contained in the QM7b database. We find that B97-3c and PBEh-3c perform best against coupled-cluster reference values yielding dipole moments with a mean absolute error (MAE) of 0.10 and 0.11 D, respectively, which is similar to the MAE of density functional theory (DFT) methods (∼0.1 D) reported earlier. Analysis of the atomic composition shows that all SE methods show good performance for hydrocarbons for which the spread of error was within 1 D of the reference data, while the worst performances are for sulfur-containing compounds for which only B97-3c and PBEh-3c show acceptable performance. We also evaluate the effect of SE optimized geometry, instead of the benchmark DFT geometry, that shows a dramatic drop in the performance of AM1 and PM3 for which the range of error tripled. Based on our overall findings, we highlight that there is an optimal compromise between accuracy and computational cost using GFN2-xTB (MAE: 0.25 D) that is 3 orders of magnitude faster than B97-3c and PBEh-3c. Thus, we recommend using GFN2-xTB for cost-efficient calculation of the dipole moment of organic molecules containing C, H, O, and N atoms, whereas, for sulfur-containing organic molecules, we suggest PBEh-3c.