Diffusion in binary mixtures: An analysis of the dependence on the thermodynamic factor

We study the diffusion process in binary mixtures using transition probabilities that depend on a mean-field potential. This approach reproduces the Darken equation, a relationship between the intrinsic and the tracer diffusion coefficients, D A and D ∗ A , through the thermodynamic factor Φ (a func...

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Detalles Bibliográficos
Autores: Di Pietro Martínez, Marisel, Hoyuelos, Miguel Luis
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2019
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/122917
Acceso en línea:http://hdl.handle.net/11336/122917
Access Level:acceso abierto
Palabra clave:MEAN FIELD THEORY
MONTE CARLO METHODS
DIFFUSION
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descripción
Sumario:We study the diffusion process in binary mixtures using transition probabilities that depend on a mean-field potential. This approach reproduces the Darken equation, a relationship between the intrinsic and the tracer diffusion coefficients, D A and D ∗ A , through the thermodynamic factor Φ (a function of the derivative of the activity coefficient against the molar fraction). The mean-field approach allows us to go beyond the Darken equation and separately specify the dependence of D A and D ∗ A on the thermodynamic factor. We obtain that Φ appears in the expression for D ∗ A , but the intrinsic diffusivity D A turns out to be independent of Φ . Experimental results taken from the literature on diffusion in metal alloys are consistent with this theoretical prediction.