Dependencies of solvation-free energy and coordination number of ions on external electrostatic fields

• Published in: Journal of molecular liquids Vol. 298; p. 112055
• Main Author: Yang, Pei-Kun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.01.2020
• Subjects: Coordination number; External electrostatic field; Local solvent density; Solvation-free energy; Coordination number; External electrostatic field; Local solvent density; Solvation-free energy
• ISSN: 0167-7322; 1873-3166
• DOI: 10.1016/j.molliq.2019.112055

An external electrostatic field (Eext) is applied to water clusters containing Na+, K+, and Ca++ to explore the dependencies of solvation-free energy (ΔGslv) and the coordination number (CN) of ions on Eext. The ΔGslv, radial distribution function [g(r)], and CN of ions are computed from molecular dynamics simulation trajectories. The results demonstrate that ΔEΔGslv [ΔGslv(Eext) − ΔGslv(Eext = 0)] increases with increasing Eext due to dielectric saturation. Eext altered the local solvent density, g(r, θ). However, the g(r) and CN of ions depended slightly on Eext. •An external electrostatic field (Eext) is applied to water clusters containing Na+, K+, and Ca++.•Solvation-free energy (ΔGslv) and coordination number (CN) of ions are computed from the simulation trajectories.•-ΔGslv decreases with increasing Eext owing to dielectric saturation.•The CN of ions depended slightly on Eext.