268124.fig.004a
(a)
268124.fig.004b
(b)
Figure 4: (a) A S0/T1-MEPSX curve for           at the CASPT2 level (see Section 2.4 for details of the CASPT2 calculations) and (b) a S0/T1-MEPSX curve for the same reaction at the UB3LYP/aug-cc-pVDZ level.