What's the rationale for choosing L-J parameters for metals? -
On comparison with Ne (rmin/2 = 1.53) in the CHARMM27 prm file with the nonbonded contact distance in the periodic system things look ok. However, for other metals, e.g. zinc, this trend is not obvious, rather it seems a bit ad hoc...so my question actually boils down to: To what extent should we use experimental values in defining force-field parameters?