Density‐functional‐theory study of α‐cyclodextrin inclusion complexes

Abstract

AbstractWe apply the density functional theory on the description of the α‐cyclodextrin (α‐CD) and the analysis of the molecular electrostatic potential (MEP) for complexes of this system with Na+, F−, CO, and N,N‐dimethyl formamide, as substrates. Four exchange‐correlation functionals were considered: one of the local density approximation, two of the generalized gradient approximation (BLYP and PBE), and one of the hybrid family. These exchange‐correlation functionals were coupled with the DZVP/A1, DZVP, and TZVP basis set functions. All complexes were fully optimized by all methods. The experimental molecular structure of the α‐CD compares better with that described by the PBE exchange‐correlation functional. The MEP analysis shows that the electrostatic is quite relevant on the intermolecular interaction for the α‐CD complexes in gas phase. Some of our results are in disagreement with those published previously with the PM3 semiempirical method and the B3LYP//PM3 method. © 2012 Wiley Periodicals, Inc.