We have disabled this feature in our calculations, as leaving it enabled would result in longer optimization trajectories; instead, these calculations are allowed to crash and are therefore omitted from figure 6c. While this feature improves the robustness of the optimization algorithm implemented in Q-Chem, it does so at the cost of longer trajectories for these pathological systems. In this scenario, our optimization algorithm will instead automatically reconstruct a new internal coordinate system, rather than falling back on Cartesian optimization. This results in a robust optimization algorithm similar to Q-Chem, without the additional cost of switching to a Cartesian optimization scheme.