The polarization-selected two-photon resonant multiphoton ionization spectra of cyclopentadiene and cyclopentadiene-d6 have been measured in the 3p-Rydberg ← X̃ region of the spectrum. The spectra were analyzed to provide experimental assignments for all three 3p-Rydberg origins and three a1, three b1, and one a2 fundamental vibrational frequencies in the 3p-Rydberg states. The allowed origins of the B1 and A1 3p-Rydberg ← X̃ transitions were not observed; Herzberg-Teller induced false origins were observed from the ground to these states in their stead. The false origins were deduced to arise from coupling of the intermediate state of the two-photon transition to a state of A1 symmetry, probably the 3A1 valence state.
|Number of pages||7|
|Journal||Journal of Physical Chemistry|
|State||Published - 1992|