Theoretical and experimental report on the determination of oxidation potentials of dihydroxyanthracene and thioxanthens derivatives

Abstract

The oxidation potentials of dihydroxyanthracene (AN) and thioxanthens (TH 1–TH 3) in acetonitrile have been calculated. The calculations have been performed using ab initio molecular orbital calculations (HF), and density functional theory (DFT) with the inclusion of entropic and thermochemical corrections to yield free energies of the redox reactions. The polarizable continuum model (PCM) was used to describe the solvent. The data were also obtained experimentally, with the aid of an electrochemical technique (cyclic voltammetry). The root-mean-square errors between the observed and calculated changes in the oxidation potential differences of TH group compounds in compare to those of the reference compound (AN) is just 0.043 V and 0.024 V for B3LYP and HF methods, respectively that provide a method by which the reduction potentials of the related molecules can be predicted more accurately. Correlation analysis between the experimental and the theoretically calculated oxidation potentials revealed that notable relations existed between the obtained oxidation potentials and the ionization potential (IP) of thioxanthens derivatives.