Why DFT-Based Tight Binding Gives a Better Representation of the Potential at Metal-Solution Interfaces than DFT Does

In modelling electrochemical interfaces it is important to treat electrode and electrolyte at the same level of theory. Density functional theory, which is usually the method of choice, suffers from a distinct disadvantage: The inner potential is calculated as the average of the total electrostatic...

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Detalles Bibliográficos
Autores: Quaino, Paola Monica, Nuñez, José Luis, Aradi, Bálint, van der Heide, Tammo, Santos, Elizabeth, Schmickler, Wolfgang
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2023
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/226244
Acceso en línea:http://hdl.handle.net/11336/226244
Access Level:acceso abierto
Palabra clave:DFT
INNER POTENTIAL
POTENTIAL OF ZERO CHARGE
TIGHT BINDING
WORK FUNCTION
https://purl.org/becyt/ford/1.4
https://purl.org/becyt/ford/1
Descripción
Sumario:In modelling electrochemical interfaces it is important to treat electrode and electrolyte at the same level of theory. Density functional theory, which is usually the method of choice, suffers from a distinct disadvantage: The inner potential is calculated as the average of the total electrostatic potential. This includes the highly localized potential generated from the nuclei. The resulting inner potential is far too high, of the order of 3.5 V, and not relevant for electrochemistry. In the density functional based tight binding (DFTB) method the electrostatic potential is much smoother, as it stems from atomic charge fluctuations with respect to neutral reference atoms. The resulting values for the electrochemical inner potential are much lower and compare well with those obtained by other, elaborate methods. Thus DFTB recommends itself as a method for treating the electrochemical interface including the inner potential.