While the ∆SCF approach is a non-empirical method for tuning functionals, experimental results can also provide valuable guidance for justifying the chosen computational scheme. As excited state properties are of particular interest for such complexes, the natural choice of experimental reference is the absorption spectra. Fig. compares the experimental absorption spectrum against spectra computed with LC-BLYP and combinations of (α, ω) along the minimal valley in the J * plot with steps 0.05 in α (see Fig. ) as well as with the popular B3LYP functional. For the Set A and Set B of optimal parameters, the transitiondensity-matrix analysis of singlet and triplet spectra is also shown.