3. Bonded distributions: Constraints hold together the aromatic rings, whereas (harmonic) bond potentials connect the polymethine bridge with the benzimidazoles (see Figure ), and the aromatic core with the tails. There are also angles and dihedrals that control the orientation of the aromatic core. A detailed list of the bonded parameters is included in Figure -S6 of the Supplementary Information. The bonded distributions of the CG model were optimised to reproduce the atomistic distributions of the respective chemical groups. To obtain the atomistic distributions, a C8S3 monomer was solvated in a water box together with a counter ion and simulated for a short time. Then, a monomer of the CG model was simulated in the same way, and its bonded parameters were tuned by adapting its reference values and/or its force constants, until there was sufficient overlap. Most bonded distributions are well reproduced, because the current mapping favoured unimodal profiles. When bimodal distributions were encountered, capturing the mean values and the width of distributions was attempted. The comparison of the bonded distributions between the atomistic and the CG model are included in Figure -S6 of the Supplementary Information.