. Author manuscript; available in PMC: 2019 Oct 9.

Published in final edited form as: J Chem Theory Comput. 2018 Sep 14;14(10):5290–5302. doi: 10.1021/acs.jctc.8b00604

Table 1.

Force field parameters and the experimental hydration free energy values for the eleven ions.

Ions	LJ parameters		Exp HFE^c
	R_min/2 (Å)	ε (kcal/mol)	(kcal/mol)
Li⁺^a	1.29591	0.04079	−113.52
Na⁺^a	1.40811	0.82103	−87.23
K⁺^a	1.76154	1.52302	−70.51
Rb⁺^b	1.81203	5.73877	−65.72
Cs⁺^a	2.09814	3.32611	−59.75
F⁻^b	2.30010	0.05887	−111.13
Cl⁻^a	2.26644	2.62588	−81.26
Br⁻^a	2.60865	1.02679	−75.28
I⁻^b	2.85549	0.93972	−65.72
Ca²⁺^a	1.36323	2.10070	−359.70
Mg²⁺^a	1.18372	0.26259	−437.38

Parameters are from the CHARMM force field³¹ as reported in the 2017 version of the CHARMM36 GROMACS toppar files following conversion to R_min/2 in Å and epsilon in kcal/mol.

Parameters are from ref³².

Experimental HFE values are from ref³³.