Figure shows the decay of the RAE (Equation ) on a double logarithmic scale. For order 6 the RAE is approximately 0.05. For higher orders than 6 the improvement becomes slower. The orange line is fitted to the RAE values for orders 1 to 6. Its slope and offset are inserted in the inset. Fig. . Normalized error of the interaction energy of all the geometric configurations shown in Figure for their respective approximation order. Overall, our (order 10) model is able to predict the interaction energies of the O - 2 -O - 2 dimer in the triplet state (Figure ) for interatomic distances equal or higher 2.5 Å where the interaction energies are below 400 kJ/mol quite successfully despite it solely being calibrated from neutral water dimer calculations. However, the lowest energy state according to our ROCCSD(T) calculations is in its singlet state and not a triplet. The reduced accuracy for the singlet state might suggests that our model is not capable to reproduce covalent bond cleavage/formation accurately. To make our model more accurate and universal, a broader collection of dimer interactions containing neutrals, anion and cation interactions would be necessary. A similar comparison with the interaction energies in the neutral O 2 dimer (Figure ) is in good agreement with our ROCCSD(T)/cc-pVTZ calculations (triplet spin, if the total spin of the interacting system equals the sum of the spins of the non-interacting system). Our model struggles, however, to reproduce covalent bond cleavage/formation. Lower spin states (singlet and triplet) ROCCSD(T)/cc-pVTZ calculations for this neutral dimer failed due to convergence problems. Fig. . Interaction energy of an O 2 + O 2 complex in the reaction coordinate shown in Figure obtained from CCSD(T)/cc-pVTZ level of theory and our calibrated model from neutral water dimer calculations (same level of theory) using an order 10 approximation.