ON THE ABSORPTION-SPECTRUM OF THE 3S RYDBERG STATE OF ACETONE

The optical absorption spectra of acetone and acetone-d6 in the 3s Rydberg region have been remeasured and reanalyzed. Activity is observed in the a1 CH3 deformation, CH3 rock, and CC stretching vibrations, as before. The two low frequency displacement subbands of the transition, + 250 and + 309 cm-1 have been reassigned; the former is twice the a2 CH3 torsion, the latter cannot be assigned. Possible photophysical implications of the large frequency shifts in the methyl-centered modes are discussed.