Ionic activity in concentrated electrolytes: Solvent structure effect revisited
Abstract
We revisit the role of the local solvent structure on the activity coefficients of electrolytes within a nonlocal dielectric function approach. We treat the concentrated electrolyte as a dielectric medium and suggest an interpolation formula for its nonlocal dielectric response. The water dielectric response is approximated based on MD simulations and experimental data, that gives strong over-screening and oscillations in the potential, which are absent in the standard "primitive model" predictions. We obtain mathematically tractable closed-form expressions for the activity coefficients, in reasonable agreement with experimental data.
- Publication:
-
Chemical Physics Letters
- Pub Date:
- January 2020
- DOI:
- 10.1016/j.cplett.2019.136915
- arXiv:
- arXiv:1905.12076
- Bibcode:
- 2020CPL...73836915L
- Keywords:
-
- Physics - Chemical Physics;
- Condensed Matter - Soft Condensed Matter
- E-Print:
- doi:10.1016/j.cplett.2019.136915