Therefore, for every stoichiometrically balanced reaction, it is evident that k ∈ products and k ∈ reactants will be equivalent and ∑ k n k µ A k will cancel, making the choice of µ A k arbitrary. This invariance proves that as long as a dataset is anchored to the same set of atomic reference species, it is internally consistent and the relative quantities required for microkinetic models will be identical regardless of the anchors selected. The following techniques for comparison and conversion of enthalpies of formation exploit this invariance, selecting "convenient" µ A k that allow for comparison of energies under different thermodynamic scenarios or between different levels of theory and for conversion of energies between relative and absolute reference states.