Electrical conductivity variations of aqueous NaCl solutions with microwave field: A molecular dynamics study

[Display omitted] •Evolution of hydration shells in NaCl solutions with microwave field was simulated.•The application of microwave field causes the EC variations in NaCl solutions.•The calculated results met with the measured results in the experiment. The slight electrical conductivity variations of sodium chloride aqueous solutions under the microwave field have been found in experiment, but the mechanism is still unclear. By applying molecular dynamics simulations, the number of water molecules in the hydration shells of sodium are examined quantitatively, we demonstrate that the outer water molecules of shell are stripped away due to the oscillations and collisions among water molecules under the microwave field, this is a microwave desolvation effect. By further study on calculating diffusion coefficient of ions, the electrical conductivity of solutions has been estimated. The result showed that as the diffusion coefficient increased by the desolvation effect, the electrical conductivity of solutions slightly enhanced. The electrical conductivity of solutions at different temperatures and concentrations agree with the measured results in the experiment.