title: Simulations of Adiabatic Electrochemical Reduction of the CF3I Molecule-Assessment of Different Models.
abstract: The kinetics and mechanism of electrochemical reduction of the CF3I molecule are studied using molecular dynamics simulations. The potential energy surface used in the simulations is based on the Newns-Anderson-Schmickler Hamiltonian and on the analytical potentials fitted to points obtained from quantum calculations for the CF3I neutral molecule and anion. Two different sets of points were used for fitting: the first obtained in vacuo1 and the second in dimethyl sulfoxide,2 which yields two models, named respectively "VAC" and "SOLV." Additionally, each model was tested with two different values of the solvent reorganization energies: λ = 0.624 eV and λ = 1 eV. The results show that both models provide results which are qualitatively similar but differ quantitatively, mainly due to a shift in the overpotential η. The electron transfer coefficient is found to vary linearly at a certain range of overpotentials, but this relation changes for larger η, where it takes a parabolic-like form. The transfer coefficient is very sensitive to the λ value: at T = 298 K and η = 0.9 V, we report values α = 0.204 obtained for λ = 0.624 eV and α = 0.28 for λ = 1 eV.
authors.affiliation: Department of Theoretical and Structural Chemistry, University of Lodz , ul. Pomorska 163/165, 91-236 Łódź, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Ignaczak