Photoisomerization to Dewar benzene

The symmetry analysis that follows is similar to that of Haller [39] and reaches identical conclusions. In Fig. 10.7, the MOs of benzene are relabeled to their right by their irreps in C, those of DB are carried over from Fig. 9.9. The non-correspondence that blocks thermal isomerization of DB on the ground-state potential energy surface was shown in Section 9.3.4.1 to be between 2( 2) and 7T+(ai). Therefore, when an electron is excited out of to 4(01), a 

Bachler has applied his extension of the Bader-Pearson-Salem approach [36] to both isomerization processes. His preliminary results indicate that vibrational modes that would be expected to contribute to the reaction coordinates for isomerization to benzvalene are indeed excited in Si and those leading to Dewar benzene are excited in S2 [41]. 

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