Infrared Photochemistry of Tetramethyldioxetane. 2. The Nature of Electronically Excited Products

The decomposition of tetramethvldioxetane (TMD) following either overtone excitation or infrared multiple photon excitation (IRMPE) under low-pressure conditions is discussed and compared to recent results obtained upon UV photoexcitation of acetone vapor. It is shown that the results are consistent with a mechanism by which IR excitation of TMD results in producing electronically excited acetone, which may be considered as a mixed state containing contributions from both the singlet and the triplet states.