This general form allows intuitive change of references. It is possible to use this method to create a thermochemical network that is referenced to the ATcT by defining the enthalpies of formation of the reference species to have the actual experimental values (instead of using the DFT values, which is equivalent to assuming HA = 0). When using gas-phase reference species, this results in the same enthalpies of formation as the method in Section 4.3.2, and when using adsorbates, this is equivalent to Section 4.3.3. Integrating the DFT data into the global thermochemical network allows to replace gas-phase DFT energies with accurate ∆ f H from the ATcT. The interested reader is referred to the SI for a more detailed discussion of the linear algebra of this approach. This approach of calculating enthalpies of formation directly from reaction enthalpies can serve as a convenient framework for new methods of combining data from various sources or identifying discrepancies in existing databases.