Both molecules show a lowest unoccupied molecular orbital (LUMO) centered on the BT core. In contrast, the highest occupied molecular orbital (HOMO) of both molecules consists of a conjugated π-electron system delocalized along the caffeine motifs and the BT center (Figures and). To gather understanding of the location of the electrons injected into BT-DCAF during the three different reduction processes that were observed in the electrochemical measurements, we modelled the HOMO of the three presumed species derived from BT-DCAF. These models suggest that upon each additional electron injection the HOMO expands gradually from the BT core towards the caffeine side units of BT-DCAF (Figure ). It has been proposed that for H2 evolution to take place under reasonable electrocatalytic conditions (mild electrochemical potentials), a hydride donor should have a 𝜟𝑮 𝑯 -equal or below 76 kcal/mol. The calculated 𝜟𝑮 𝑯 -of the BT-DCAFH4 species was 50.8 kcal/mol (Table ). The 𝜟𝑮 𝑯 -of BT-DCAFH4 hydride species corresponds to an organic hydride with moderate to strong H - donating ability. Therefore, electrocatalytic H2 evolution should be feasible using the hydride BT-DCAFH4 electrochemically generated from BT-DCAF molecule.