Effect of basis set superposition error on the water dimer surface calculated at Hartree-Fock, Moller-Plesset, and density functional theory levels
Effect of basis set superposition error on the water dimer surface calculated at Hartree-Fock, Moller-Plesset, and density functional theory levels
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DOI：
10.1021/jp9842188
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发表时间：
1999-03-18
影响因子：
2.9
通讯作者：
Dannenberg, JJ
中科院分区：
文献类型：
--
作者：
Simon, S;Duran, M;Dannenberg, JJ
提出了使用 D95++(d,p) 基组在不同 MP 和 DFT 水平下对水二聚体进行平衡 (CP) 校正优化。 MP2（完整）计算预测相互作用能为 -4.75 kcal/mol，接近“MP2 极限”并报告具有大基组的 MP2 计算。 DFT (B3PLYP) CP 校正优化提供了最佳相互作用能 (-5.22 kcal/mol)。正如预期的那样，优化的 O ... O 分离在 CP 优化的表面上比在未校正的表面上更大。这些增加改善了 DFT 预测的分离，并使 MP 方法预测的分离恶化。然而，MP2 表面非常平坦，以至于计算结果与实验值一致所需的 O ... O 分离畸变需要小于 0.1 kcal/mol。
Counterpoise (CP) corrected optimizations of water dimer using the D95++(d,p) basis set at various levels of MP and DFT are presented. The MP2(full) calculations predict an interaction energy of -4.75 kcal/mol, close to the "MP2 limit" and to reported MP2 calculations with much large basis sets. DFT (B3PLYP) CP-corrected optimization provided the best interaction energy (-5.22 kcal/mol). The optimized O ... O separations are larger on the CP-optimized than on the uncorrected surface, as expected. These increases improve the separations predicted by DFT and worsen those predicted by the MP methods. However, the MP2 surface is so flat that the distortions of the O ... O separations needed to make the calculations agree with the experimental value require less than 0.1 kcal/mol.