“…The planes of the donor and acceptor π systems in molecule 3 are slightly twisted, which has been identified as a contributing factor to the magnitude of the paramagnetic current density response upon π → π* excitation in ref . Indeed, in a recent study of the 2PA strengths of essentially perfectly planar coumarin derivatives, MGGA and cMGGA results obtained using the implementation from GF23 were in much closer agreement than found for the push–pull systems studied here . Importantly, Figure shows no correlation of deviations due to gauge dependence and other method errors (e.g., errors from the density functional approximations or basis sets), emphasizing the fundamentally erratic and arbitrary nature of the former.…”