(ii) a stacked column of TBAP molecules from the TBAP-α structure suggest that the effect of packing on the TBAP potentials should be small (see SI, section 1.5, Table , and Figures and), in keeping with the similarity of the absorption spectra for amorphous and crystalline analogues. These DFT calculations also indicate that TBAP-α and its amorphous counterpart should both have the required driving force for proton reduction and ascorbic acid oxidation.