In the 15 Å box, electrostatic interaction cut-offs were 0.7 nm with a 0.12 nm spacing with CHARMM and 0.7 nm with a 0.125 nm spacing with Amber. For CHARMM the Lennard-Jones interactions were force switched off between 0.5 and 0.7 nm, while for Amber they were cut off at 0.7 nm and a dispersion correction was applied to the energy and pressure. We used the CHARMM TIP3P water model with the non-zero Lennard-Jones parameters on hydrogen atoms (i.e., mTIP3P) and plain TIP3P for the CHARMM and Amber systems, respectively. In the case of CHARMM we also assessed the impact of using the OPC water model on the solvation structure and measured free energies.