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Updated: Aug 11, 2026

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Structures of inclusion complexes of halogenbenzoic acids and alpha-cyclodextrin based on AM1 calculations
Martin Pumera1, Lubomír Rulísek
1Department of Chemistry, Autonomous University of Barcelona, Bellaterra, Spain. martin.pumera@uab.es
Abstract:
Semi-empirical quantum mechanics calculations using AM1 (Austin Method 1) were carried out for various host-guest combinations of alpha-cyclodextrin and mono-halogen benzoic acids. The energetically favorable inclusion structures were identified. The AM1 results show that alpha-cyclodextrin complexes with mono-halogen benzoic acid acids (where the halogen is chlorine, bromide, iodine) as guest compounds are more stable in the "head first" position than in the "tail-first" position for meta and para isomers while ortho mono-halogen benzoic acids complexes with alpha-cyclodextrin are more stable in "tail-first" position. The calculated structures were found to be in good agreement with those obtained from crystallographic databases.
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