The WT-MetaD simulation of system 4 has been run using the difference between the distance between the center of geometry of CBPQT 4+ and the oxygen atom of the last PEG of one lateral chain and the distance between the center of geometry of the ring and the oxygen atom of the last PEG of the other lateral chain (CV1) and the torsional angle ψ between the two naphthalenes (CV2) as CVs. The bias has been added every 2 ps, using Gaussians with an initial height of 1 kJ/mol, a width of 0.2 nm for CV1 and 0.2 rad for CV2, and a bias factor of 20.