The following simulation parameters were based on the recommended Martini run parameters . The Verlet cutoff scheme with a straight cutoff of 1.1 nm was used. Coulomb interactions were treated with the reactionfield approach, using the same cutoff radius and a relative dielectric constant of ϵ r = 15. Constraints were included using the LINCS algorithm. Periodic boundary conditions were applied for all the coarse-grained simulations. The optimized models produced by Swarm-CG were subsequently used for the free energy calculations. As in the Martini 3 main publication, only neutral molecules were considered for these calculations . The coarse-grained fragments were respectively solvated in water, hexadecane, chloroform and water-saturated octanol, with a mole fraction of 0.25:0.75 for the latter. The cubic simulation box had an edge length of 5 nm in each case.