When comparing the distributions from the reference atomistic simulations and the CG data, some discrepancies can be observed. Most of the discrepancies here are connected to bimodal distributions of bonded terms. Symmetrical periodic dihedrals can potentially be better fitted in GROMACS exploring the different multiplicities, including combinations of proper cosine dihedrals or by using the Ryckaert-Bellemans function. However, the accurate fitting of nonsymmetrical dihedrals as presented in Figure can be challenging. Further refinement could be achieved via tabulated potentials in GROMACS or direct implementation of more complex functional forms directly in codes such as OpenMM .