The situation for electrical conductivity is slightly more complicated as multiple methods exist to compute electrical conductivity in electrolyte. In previous studies, one often first determines the self-diffusion coefficient from the mean square displacement (MSD), then use the Nernst-Einstein relationship to obtain the conductivity. This approach is not rigorous because the Nernst-Einstein equation is only applicable to ideal dilute solutions, when the correlation between the diffusion of positive and negative ions can be neglected. Although more accurate methods exist (such as the mutual diffusion coefficient method ), but they have relatively poorer convergence in our systems. (TCF). The instantaneous ionic current is computed as: