2023/07/10 by S M Rezwanul Islam, Islam, S M Rezwanul, Foroogh Khezeli +5
Chemistry · Engineering · Physics and Astronomy · #Chemical Physics (physics.chem-ph) #FOS: Physical sciences #Molecular Junctions and Nanostructures #Photochemistry and Electron Transfer Studies #Spectroscopy and Quantum Chemical Studies
paper · pdf · doi:10.48550/arxiv.2307.04551
openalex publication_date 2023/07/10 · openalex created_date 2023/07/12 · openalex updated_date 2026/07/28
We have developed and implemented an implicit electrolyte model in the Vienna Ab initio Simulation Package (VASP) that includes nonlinear dielectric and ionic responses as well as a nonlocal definition of the cavities defining the spatial regions where these responses can occur. The implementation into the existing VASPsol code is numerically efficient and exhibits robust convergence, requiring computational effort only slightly higher than the original self-consistent continuum solvation (SCCS) model. The nonlinear+nonlocal model is able to reproduce the characteristic `double hump' shape observed experimentally for the differential capacitance of an electrified metal interface while preventing the `leakage' of the electrolyte into regions of space too small to contain a single water molecule or solvation ion. The model also gives a reasonable prediction of molecular solvation free energies as well as the self-ionization free energy of water and the absolute electron chemical potential of the standard hydrogen electrode. All of this, combined with the additional ability to run constant potential density functional theory calculations, should enable the routine computation of activation barriers for electrocatalytic processes.