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Mesoscopic nonequilibrium thermoydnamics. Application to interfacial phenomena. Miguel Rubi. Dynamics of Complex Fluid-Fluid Interfaces Leiden, 2011. Interfaces. The interface is a thermodynamic system ; excess properties ; Local equilibrium holds .
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Mesoscopicnonequilibriumthermoydnamics Applicationtointerfacialphenomena Miguel Rubi Dynamics of Complex Fluid-Fluid Interfaces Leiden, 2011
Interfaces • The interface is a thermodynamicsystem; excessproperties; Local equilibriumholds. • Transport and activatedprocessestake place • Thestate of thesurface can bedescribedbymeans of aninternalcoordinate shear bound free
Activation shear Examples: Chemicalreactions, adsorption, evaporation, condensation, thermionicemmision, fuel cells…. stick slip Activation: toproceedthesystem has tosurmount a potentialbarrier; nonlinear NET: provides linear relationshipsbetweenfluxes and forces
Nonequilibriumthermodynamics • Global description of nonequilibriumprocesses (k0; ω0) Shorterscales: memorykernels (Ex.generalyzedhydrodynamics, non-Markovian) • Description in terms of averagevalues; absence of fluctuations Fluctuations can beincorporatedthroughrandomfluxes (fluctuatinghydrodynamics) • Linear domain of fluxes and thermodynamicforces
Chemical reactions Law of mass action linearization Conclusion: NET onlyaccountsforthe linear regime.
Activation Unstable substance Final product Naked-eye: Sudden jump Watching closely Diffusion Progressive molecular changes
Translocation of ions (through a protein channel) Biological membrane short time scale: local equilibrium along the coordinate Local, linear Global, non-linear biological pumps, chemical and biochemical reactions Arrhenius, Butler-Volmer, Law of mass action
Protein folding Intermediate configurations, same as for chemical reactions
Molecularmotors Energy transduction, Molecular motors
Activated process viewed as a diffusion process along a reaction coordinate From local to global:
What can we learn from kinetic theory? Boltzmann equation Chapman-Enskog LMA J. Ross, P. Mazur, JCP (1961)
Thermodynamics and stochasticity J.M. Vilar, J.M. Rubi, PNAS (2001) Probability conservation: Entropy production: Fokker-Planck
Molecular changes: diffusionthrough a mesoscopiccoordinate D. Reguera, J.M. Rubi and J.M. Vilar, J. Phys. Chem. B (2005); FeatureArticle Second law
Relaxation equations J.M. Rubi, A. Perez, Physica A 264 (1999) 492 hydrodynamic Fick Maxwell-Cattaneo Burnett
References • A. Perez, J.M. Rubi, P. Mazur, Physica A (1994) • J.M. Vilar and J.M. Rubi, PNAS (2001) • D. Reguera, J.M. Rubi and J.M. Vilar, J. Phys. Chem. B (2005); Feature Article • J.M. Rubi, Scientific American, November, 40 (2008)
1 2 ( ) 2 1 0 Adsorption Chemisorbed Physisorbed
Langmuirequation I. Pagonabarraga, J.M. Rubi, Physica A, 188, 553 (1992)
Evaporation and condensation D. Bedeaux, S. Kjelstrup, J.M. Rubi, J. Chem. Phys., 119, 9163 (2003)
Stick-slip transition shear stick slip C. Cheikh, G. Koper, PRL, 2003
Conclusions • MNET offers a unified and systematicschemetoanalyzedissipativeinterfacialphenomena. • Thedifferentstates of thesurface are characterizedby a reactioncoordinate. • Chemicalreactions, adsorption, evaporation, condensation, thermionicemmision, fuel cells….