Transferable Ion Force Fields in Water from a Simultaneous Optimization of Ion Solvation and Ion–Ion Interaction

• DOI: 10.1021/acs.jpcb.1c05303
• Publication Date: 2021-07-22T17:35:06Z
• Authors: Philip Loche; Patrick Steinbrunner; Sean Friedowitz; Roland R. Netz; Douwe Jan Bonthuis
• Keywords: Force Field; Point particle

The poor performance of many existing nonpolarizable ion force fields is typically blamed on either the lack explicit polarizability, absence charge transfer, or use unreduced Coulomb interactions. However, this analysis disregards large and mostly unexplored parameter range offered by Lennard-Jones potential. We a global optimization procedure to develop water-model-transferable for ions K+, Na+, Cl–, Br– in complete space all interactions using standard mixing rules. No extra-thermodynamic assumption necessary simultaneous four pairs. After an with respect experimental solvation free energy activity, reproduce concentration-dependent density, ionic conductivity, dielectric constant high accuracy. field fully transferable between simple point charge/extended intermolecular potential water models. Our results show that thermodynamically consistent these needs only