In Fig. we have represented the evolution of the transition probabilities (P S 2 →S 1 ) for the three different levels. From Fig. , it is clear that neither the PBE-LZ probabilities nor the PBE-FS probabilities represent a completely reliable approximation to the reference PBE0-FS transition probabilities. However, a relatively good correlation is observed. In particular, whenever the reference PBE0-FS transition probabilities are large, the PBE-LZ probabilities are also relatively large. For some reason this is less obvious for the PBE-FS curve.