CRYSTAL STRUCTURE OF A β-CYCLODEXTRIN·ETHANOL·OCTAHYDRATE

Abstract
Ring-shaped β-cyclodextrin(β-CD) molecules as hosts enclosing ethanol and three water molecules as guests are arranged in cage-type structure produced by the twofold screw axis of the monoclinic crystal system; space group P21, a=21.115, b=10.190, c= 15.214Å, β=111.4°, Z=2. Between the β-CD, five waters are located. Each of the guest ethanol, two waters and three primary hydroxyls are distributed at two alternative sites. The possibility of a structural transition from cage to channel type is considered.