Driving forces and electronic structure in β-cyclodextrin/3,3′-diaminodiphenylsulphone complex

The complexation of 3,3'-diaminodiphenylsulphone (3DADPS) by beta-cyclodextrin (beta-CD) was analyzed using PM6 method and several combinations of ONIOM2 hybrid calculations in vacuum and in water. The objective was to elucidate electronic structure, driving forces and energy changes that accompany the complexation. Complexation and interaction energies, thermodynamic parameters, chemical reactivity and site selectivity of the molecular systems have been investigated. The results show that the inclusion process is exothermic. NBO calculations reveal that hydrogen bonding between beta-CD and 3,3'-diaminodiphenylsulphone is a major factor contributing to the overall stability of the complex. (C) 2014 Elsevier B.V. All rights reserved.