Investigating the Electrochemical Double Layer with Quantum-Chemical Simulations and Implicit Solvation Models
Alessandro Mangiameli1, Christopher J Stein1,2
1Department of Chemistry and Catalysis Research Center, TUM School of Natural Sciences, Technical University Munich, Garching, Germany.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|August 11, 2026
Summary
The dielectrically consistent reference interaction site model (DRISM) shows promise for modeling electrochemical double layers. Adjusting metal-ion parameters improves accuracy over default mixing rules, enhancing model performance.
Area of Science:
- Computational chemistry
- Physical chemistry
- Electrochemistry
Background:
- Implicit electrolyte models are crucial for simulating electrochemical interfaces.
- Accurate modeling of the electrochemical double layer requires precise parameterization of ion-solvent and ion-electrode interactions.
Purpose of the Study:
- To evaluate the dielectrically consistent reference interaction site model (DRISM) as an implicit electrolyte framework.
- To compare DRISM with the Poisson-Boltzmann model and explicit molecular dynamics for electrochemical double layer simulations.
- To investigate the impact of Lennard-Jones parametrization on DRISM performance.
Main Methods:
- Utilized the DRISM framework for implicit electrolyte modeling.
- Employed the gold-electrolyte interface as a test case.
- Analyzed solvent and ionic density profiles, differential capacitance, and CO adsorption solvation energy.
Main Results:
- DRISM performance is highly sensitive to Lennard-Jones parameters for metal-ion and metal-water interactions.
- Default Lorentz-Berthelot mixing rules lead to inaccurate Na+ accumulation and increased differential capacitance.
- Pair-specific metal-ion parameters improve model symmetry and flexibility.
Conclusions:
- Pair-specific parameters enhance DRISM accuracy for electrochemical double layer modeling compared to standard mixing rules.
- DRISM with optimized parameters offers a more flexible and accurate approach for future electrochemical studies.
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