Comparative dielectric studies of aqueous D-arabitol and xylitol solution using a time domain reflectometry technique (TDR)

Abstract

This research employs TDR to demonstrate the complex permittivity spectra for aqueous xylitol and d-arabitol solution across an extensive frequency spectrum span from 10 MHz to 30 GHz and this data were subjected to analysis through the application of the Cole-Davidson Model, utilizing a non-linear Least Squares fitting approach to determine the parameters associated with dielectric relaxation. The experimental measurements were performed at four different temperatures and different volume fractions of water. The comparative analysis of the dielectric parameters reveals that there is increase dielectric constant (ε₀) with increasing volume fraction of water and the relaxation time (τ) decreases for both the system, having greater magnitude for aqueous xylitol than aqueous D-arabitol suggesting increased interaction with solutes. This study investigates intermolecular interactions through the application of the Kirkwood correlation factor in conjunction with thermodynamic parameters and higher hydration parameter in aqueous xylitol solution than D-arabitol signifies effect of conformation of OH group. The theoretical dielectric constant of the mixture was calculated utilizing the hydrogen bonding framework given by Alenka Luzar.