π-Stacked polyphenolic dimers: A case study using dispersion-corrected methods

• Published in: Chemical physics letters 2013-07, Vol.578, p.120-125
• Main Authors: Bayach, I., Sancho-García, J.C., Di Meo, F., Weber, J.-F.F., Trouillas, P.
• Format: Article
• Language: English
• Subjects: Chemical Sciences; or physical chemistry; Theoretical and
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/j.cplett.2013.05.064

[Display omitted] •π-Stacking complexation in natural compound prototypes is described.•DFT-D2/D3 and DFT-NL are assessed with respect to SCS-MP2.•A new b-parameter is proposed for the B(3)P86-NL functional.•The strategy DFT-NL//DFT-D is relevant and reliable enough. The accuracy of dispersion-corrected calculations (DFT-D2, DFT-D3 and DFT-NL) is assessed here, with large basis sets (def2-QZVP) to avoid incompleteness effects, for the most stable structure of a real-world polyphenol dimer chosen as an appropriate model. Natural polyphenols form such complexes with π-stacking playing a key stabilizing role. Our benchmark calculations predict its existence favored by 22–24kcal/mol with respect to the isolated monomers, mainly driven by both π–π and H-bonding interactions. The adequate comparison of lower-cost DFT-based methods allowed bracketing their expected accuracy. These results thus pave the way towards reliable studies of challenging aggregation processes of natural products.