Here, ϵ ϵ L J is the Lennard-Jones energy parameter and σ σ i j = ( σ σ i + σ σ j ) / 2 is the average of the individual Lennard-Jones distance parameters for particles i and j. Using a truncated form of the potential is computationally efficient while preventing the ions from overlapping or coalescing, something that would be clearly unphysical.