The polycrystalline inclusion complexes (beta-CD)(2).TeI7.17H(2)O and (beta-CD)(2).BiI7.17H(2)O have been investigated via dielectric spectroscopy over a frequency range of 0-100 kHz and the temperature range of 140-425 K. Furthermore, a DSC study was carried out in the range of 273423 K, whereas the Raman spectra (303-393 K) of beta-Te were compared to the previously examined ones of beta-Bi. In the case of beta-Te an important percentage of normal H-bonds is transformed into flip-flop ones (T-tans = 216.8 K) as it comes out by the corresponding epsilon' (T), epsilon '' (T) and phi(T) variations at T<250 K (Delta epsilon' = 18.6, epsilon ''(max) = 4.8, phi(min) = 69.9 degrees). In beta-Bi the greatest percentage of normal H-bonds is transformed into those of the flip-flop type (T-trans = 223.6 K, Delta epsilon' = 49.6, epsilon ''(max) = 16, phi(min) = 58.6 degrees) producing a disordered H-bonding network of a much higher density than that of beta-Te. At T>250 K, the ac-conductivity (In sigma vs. 1/T) of these systems follows an Arrhenius behaviour with activation energies 0.54 and 0.46 eV for beta-Te and 0.38, 0.68 and 0.58 eV for beta-Bi. This exponential increment reflects the combined contributions of the water network, the oscillating cations and the dehydration process. The abrupt increase of the ac-conductivity at T>398.5 K is caused by the sublimation of iodine. The temperature-dependent Raman spectra of beta-Te exhibit the band shift of 178 -> 172 cm(-1) which is identical to that of beta-Bi, implying a similar elongation of their I-2 units. The high density flip-flop hydrogen-bonding network in the latter complex seems to play a key role in limiting the Lewis base character of I-3(-). (C) 2008 Elsevier B.V. All rights reserved.