DIELECTRIC INVESTIGATION OF BETA-CYCLODEXTRIN HYDRATES AND INCLUSION COMPLEXES

The dielectric behavior of beta-CD hydrates and beta-CD inclusion complexes with various organic guest molecules has been studied mainly by the thermally stimulated depolarization current (TSDC) method in the temperature range 80 to 300 K. Some preliminary measurements have also been carried out by conventional ac techniques at room temperature. Results are discussed in relation to the corresponding structure as determined by X-ray diffraction and are compared with differential scanning calorimetry data reported in the literature. The main high-temperature (200 to 280 K) peak recorded with the TSDC method is shown to be directly related to a phase transition occurring near the peak temperature. Water enclosed in the beta-CD cavity seems to play a very important role as far as this transition is concerned.