Do all molecules have a measurable redox potential?
Although all molecules do have frontier orbitals, in practice these are not always accessible in a voltammetry experiment. Molecules for which a redox potential can be measured are referred to as electrochemically active. Examples of electrochemically active molecules include organic molecules with extended p-systems (e.g., aromatic molecules) and transition metal complexes. It should also be noted that some systems have the ability to undergo more than one oxidation or reduction, and hence have more than one redox potential.
