As the second test, we compute the Pourbaix diagram for 2,2-propionate ether anthraquinone (abbreviated 2,2PEAQ), which is recently experimentally investigated by Amini et al. Our database contains the core structure, but not the functional group in ref. We only look at two-proton two-electron transfer reactions. Figure shows its molecular structure as well as the square-scheme representation of reactions. In addition to DFT, structural models using FPs were used to calculate the related quantities.