Dielectric Properties of Aqueous Solutions of Alkali Metal Sulfates in the Centimeter and Millimeter Bands

Abstract

The complex permittivity spectra of aqueous solutions of sulfates of Li⁺, Na⁺, K⁺, and Cs⁺ at 298 K were analyzed. It was found that, within the frequency range 7–110 GHz, only one Debye component is observed (which characterizes the total change in the hydration state of water in salt solutions), and there is no separation into hydration shell, transition layer, and bulk water. High-frequency data were used to determine the static permittivities of the solutions over a wide concentration range and the relaxation times, which represent the structural dynamics of water molecules in the studied solutions.