Effect of Anion Hydrophobicity on the Oxidation of Ferrocene‐Terminated Monolayers

Self‐assembled monolayers (SAMs) terminated with ferrocene () moieties are a popular model system for electron transfer processes at solid‐liquid interfaces. Numerous experimental studies have found a correlation between the hydrophobicity of anions in the electrolyte and the redox potential. In this computational study, the redox potential is calculated for various anion species and SAM configurations using classical molecular dynamics. Thermodynamic integration and the constrained charge method are used to determine the redox potential as the free energy change associated with electron transfers from the moieties to the electrodes. The results show the anticipated lower redox potentials for hydrophobic anions and allow the study of changes at the solid‐liquid interface at the atomistic level.