We have observed a vibrational progression of C2H22+with double charge transfer (DCT) spectroscopy. From an exploratory calculation, the progression is assigned to the symmetric C-C stretching mode of the lowest singlet1Δgstate with linear geometry. The observed structure is well reproduced with the theoretical Franck-Condon (FC) factors obtained from the potential curves of the1Δgand first-excited1Σg+states along the normal C-C stretching coordinate. Multi-reference CI calculations reveal a predominant contribution of the1Δgstate. These results suggest that the DCT process can probe dicationic states of polyatomic molecules like acetylene with resort to the FC principle. © 2001 Elsevier Science B.V.
Furuhashi, O., Kinugawa, T., Masuda, S., Yamada, C., & Ohtani, S. (2001). Double charge transfer spectroscopy of acetylene dication C2H22+at vibrational resolution. Chemical Physics Letters, 342(5–6), 625–630. https://doi.org/10.1016/S0009-2614(01)00636-4