Energy landscapes of nucleophilic substitution reactions: A comparison of density functional theory and coupled cluster methods
Energy landscapes of nucleophilic substitution reactions: A comparison of density functional theory and coupled cluster methods
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亲核取代反应的能量景观：密度泛函理论和耦合簇方法的比较
DOI：
10.1002/jcc.20653
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发表时间：
2007
影响因子：
3
通讯作者：
F. Bickelhaupt
中科院分区：
文献类型：
--
作者：
M. Swart;M. Solà;F. Bickelhaupt
我们对密度泛函理论（DFT）的性能进行了详细的评估，以描述广泛的亲核取代（SN2）反应的势能面（PES），其中包括对碳、氮、硅和硫的亲核攻击。特别地，我们研究了局部密度近似（LDA）、广义梯度近似（GGA）、元GGA以及混合DFT再现接近基集极限的高水平耦合簇（CCSD(T)）基准的能力。最精确的GGA、meta - GGA和杂化官能团在反应物络合、中心势垒、总势垒和反应能方面，相对于耦合簇数据的平均绝对偏差约为2 kcal/mol。对于三个非局部DFT类，发现最好的泛函是OPBE (GGA), OLAP3 （meta - GGA）和mPBE0KCIS（混合DFT）。流行的B3LYP函数还不错，但性能比最好的GGA函数差得多。此外，我们还将几个密度泛函的几何形状与参考CCSD(T)数据进行了比较。对于能量（OPBE， OLYP）表现最好的GGA官能团，对于键长平均绝对偏差为0.06 Å和0.6°的几何形状也表现最好，甚至优于最佳的元GGA官能团和杂化官能团。考虑到gga相对于meta - gga和杂化官能团（更不用说耦合簇）的计算量减少，我们推荐使用精确的gga，如OPBE或OLYP来研究SN2反应。©2007 Wiley期刊公司计算机学报，2007
We have carried out a detailed evaluation of the performance of all classes of density functional theory (DFT) for describing the potential energy surface (PES) of a wide range of nucleophilic substitution (SN2) reactions involving, amongst others, nucleophilic attack at carbon, nitrogen, silicon, and sulfur. In particular, we investigate the ability of the local density approximation (LDA), generalized gradient approximation (GGA), meta‐GGA as well as hybrid DFT to reproduce high‐level coupled cluster (CCSD(T)) benchmarks that are close to the basis set limit. The most accurate GGA, meta‐GGA, and hybrid functionals yield mean absolute deviations of about 2 kcal/mol relative to the coupled cluster data, for reactant complexation, central barriers, overall barriers as well as reaction energies. For the three nonlocal DFT classes, the best functionals are found to be OPBE (GGA), OLAP3 (meta‐GGA), and mPBE0KCIS (hybrid DFT). The popular B3LYP functional is not bad but performs significantly worse than the best GGA functionals. Furthermore, we have compared the geometries from several density functionals with the reference CCSD(T) data. The same GGA functionals that perform best for the energies (OPBE, OLYP), also perform best for the geometries with average absolute deviations in bond lengths of 0.06 Å and 0.6°, even better than the best meta‐GGA and hybrid functionals. In view of the reduced computational effort of GGAs with respect to meta‐GGAs and hybrid functionals, let alone coupled cluster, we recommend the use of accurate GGAs such as OPBE or OLYP for the study of SN2 reactions. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2007