Assessment of Density Functionals for Intramolecular Dispersion-Rich Interactions.
Assessment of Density Functionals for Intramolecular Dispersion-Rich Interactions.
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DOI：
10.1021/ct800231f
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发表时间：
2008-09
影响因子：
5.5
通讯作者：
T. Mourik
中科院分区：
文献类型：
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作者：
T. Mourik
一系列的密度泛函理论方法，包括传统的杂化和亚杂化泛函，双杂化泛函，和DFT-D（DFT增强与经验色散项）进行了评估，他们的能力来描述三个最小值沿着的一个特定的Tyr-Gly构象的Gly旋转曲线。先前的工作表明，这些最小值对分子内分散和基组叠加误差敏感，后者使具有小到中等大小基组的MP2计算不适合描述该分子。比较了CCSD（T）/CBS参考曲线的能量曲线，以确定CSCD（T）扭转角的变化。杂合泛函和元杂合PWB 6 K未能预测所有三个最小值;元杂合泛函M05-2X和M06-2X以及非杂合Meta泛函M06-L以及双杂合mPW 2-PLYP和B3 LYP-D方法确实找到了所有三个最小值，但低估了具有旋转C-末端的两者的相对稳定性。最好的性能是由所采用的最精细的密度泛函理论模型mPW 2-PLYP-D提供的。只有M06-2X和mPW 2-PLYP-D预测了三个最小值的稳定性的正确顺序。
A range of density functional theory methods, including conventional hybrid and meta-hybrid functionals, a double-hybrid functional, and DFT-D (DFT augmented with an empirical dispersion term) were assessed for their ability to describe the three minima along the ϕGly rotational profile of one particular Tyr-Gly conformer. Previous work had shown that these minima are sensitive to intramolecular dispersion and basis set superposition error, the latter rendering MP2 calculations with small to medium-sized basis sets unsuitable for describing this molecule. Energy profiles for variation of the ϕGly torsion angle were compared to an estimated CCSD(T)/CBS reference profile. The hybrid functionals and the meta-hybrid PWB6K failed to predict all three minima; the meta-hybrid functionals M05-2X and M06-2X and the nonhybrid meta functional M06-L as well as the double-hybrid mPW2-PLYP and the B3LYP-D method did find all three minima but underestimated the relative stability of the two with rotated C-terminus. The best performance was delivered by the most elaborate density functional theory model employed: mPW2-PLYP-D. Only M06-2X and mPW2-PLYP-D predicted the correct order of stability of the three minima.