Depending on the selected dimensionality and boundary conditions, the evolutionary algorithms CPSO and DE, as implemented in the stochopy package , were adopted for the force field parameter fitting. The swarm size was adjusted according to the number of parameters to be optimised. For all CPSO calculations, the parameters γ = 1, φ p = φ g = 1.49618, and ω = 0.7298 were chosen. In optimisation runs with the DE algorithm, the 'best2bin' differential evolution strategy (see supplementary material C.4) was used with a mutation constant of F = 0.5 and a crossover constant of CR = 0.9.