Dielectric dispersion and hydrogen bonding interactions study of aqueous D-mannitol using time domain reflectometry

Abstract

The measurement of complex dielectric permittivity of binary mixtures of D-mannitol and water have been carried out in the frequency range of 10 MHz to 30 GHz using time domain reflectometry (TDR) technique. Measurements were done at different temperatures ranging from 5°C to 25°C for different weight fractions of D-mannitol (0 < W_M ≤ 0.18) in water. The dielectric relaxation behaviour of these mixtures is explained using Cole–Davidson model. The dielectric parameters such as static dielectric constant and relaxation time for the mixtures have been evaluated. The activation energy decreases with increased D-mannitol content in the mixture. The molecular interaction between D-mannitol and water molecules is discussed using the Kirkwood correlation factor and Thermodynamic parameters.

Keywords:

• dielectric relaxation
• time domain reflectometry
• Kirkwood correlation factor

Acknowledgements

We thank Prof. S.C. Mehrotra, Dept. of Computer Science, Dr B.A.M. University, Aurangabad, for fruitful discussion. We are thankful to Dr G.N. Shinde, Principal, Indira Gandhi College, CIDCO, Nanded, for encouragement.