. Author manuscript; available in PMC: 2019 Sep 28.

Published in final edited form as: J Phys Chem B. 2018 Oct 29;122(44):10126–10142. doi: 10.1021/acs.jpcb.8b09678

Table 2.

Coefficient of self-diffusion for sodium and potassium in NaCl and KCl solutions

Concentration	D_Na+ (Å²/ps)	D_K+ (Å²/ps)	D_Na+/D_K+
0.1 M	0.236	0.301	0.78
0.5 M	0.190	0.300	0.63
1.0 M	0.186	0.288	0.65

MD results no salt solutions taken from Wonpil Im.⁸³ All the simulated systems consist of 2750 water molecules in a periodic cubic box of ~44 Å with different number of ions according to different concentrations; 5 ion pairs (0.1M), 25 (0.5M), 50 (1M). The MD simulations were performed using the CHARMM program⁴⁸ with the TIP3 water model⁴⁹ and LJ parameters for the ions from Beglov and Roux.⁵² Water geometry was kept fixed with SHAKE.⁵⁷ MD trajectories were generated with a time step of 2 fs at constant pressure (1 atm) and temperature (300 K) in the CPT ensemble using PME.⁵⁸