title: Extension of Marcus picture for electron transfer reactions with large solvation changes.
abstract: The standard Marcus theory of charge transfer reaction in solution, relying on a Gaussian solvation picture, or, equivalently, on a linear response approximation, and involving two parameters, the reorganization energy and the reaction free-energy parameter, may fail when the solvation has a different character in the reactant and product state. We propose two complementary theoretical extensions of Marcus theory applying to those cases, based either on a two-Gaussian-states solvation picture, or on a non-Gaussian solvation picture. As illustration, we show that such situations arise even for simple half oxido-reduction reactions involving the Cu(+)/Cu(2+) or Ag(0)/Ag(+) couples, for which electron transfer free-energy surfaces have been generated using first-principle molecular dynamics simulations. The two theoretical extensions are shown to exhibit the correct nonlinear response behavior and to reproduce the simulation results quantitatively, whereas a simple one-Gaussian-state Marcus description breaks down.
authors.affiliation: Ecole Normale Supérieure, Département de Chimie, UMR 8640 ENS-CNRS-UPMC, 24 Rue Lhomond, 75005 Paris, France.
authors.forename: Rodolphe
authors.initials: R
authors.lastname: Vuilleumier
authors.forename: Kafui A
authors.initials: KA
authors.lastname: Tay
authors.forename: Guillaume
authors.initials: G
authors.lastname: Jeanmairet
authors.forename: Daniel
authors.initials: D
authors.lastname: Borgis
authors.forename: Anne
authors.initials: A
authors.lastname: Boutin
mesh_terms: D003300:Copper / Q000737:chemistry; D004583:Electrons; D056004:Molecular Dynamics Simulation; D010084:Oxidation-Reduction; D012834:Silver / Q000737:chemistry; D012997:Solvents / Q000737:chemistry
chemical_list: D012997:Solvents; D012834:Silver; D003300:Copper