An analytical expression for dielectric decrement law

Abstract

Dielectric decrement means that the dielectric constant declines with the increase in the ionic concentration of the system, and it is found that, in the dilute solution, the law of the dielectric decrement is linear. However, the dielectric decrement law is unknown when the concentration of the solution is very high, and the current nonlinear fitting formula about the law of dielectric decrement is only correct in the cases of low or not very high concentrations. However, in the case of extremely high concentrations, its prediction is zero and is obviously unreasonable or incorrect. Therefore, a new expression should be and has been proposed to describe the relation between the dielectric constant and the concentration in this paper. In addition, the numerical calculations show that almost the same results can be obtained by the new and previous formulas when the concentration is not very high, but unlike the previous ones, the dielectric constant predicted by the new formula will tend to be fixed and greater than the zero value in the case of extremely high concentrations.