Double charge transfer spectroscopy of NO2+ at vibrational resolution: application of Franck–Condon analyses to a dicationic system

Double-charge-transfer spectroscopy ofO22+: Band analyses of low-lying repulsive states

“…Details of the apparatus are described elsewhere [16]. By using this energy selector, the resolution in the present work has been much improved in comparison with the previous DCT spectrum [5]; the overall instrumental resolution of the present experiment was about 140 meV (full width at half maximum) as estimated from the measured width of argon peaks.…”

“…In comparison with other methods at vibrational resolution, this method has the following advantage: direct comparison between the experimental and theoretical spectrum may be possible by virtue of the apparent propensity rules underlying the DCT process, i.e., the spinconservation rule and the Franck-Condon (FC) principle. The validity of these propensity rules has been confirmed and the unique opportunity of DCT spectroscopy to study molecular dications has been demonstrated for N 2 2+ , CO 2+ [15], and NO 2+ [16].…”

“…For comparison with the experimental band shapes, we have calculated the theoretical FC profiles using the wavepacket method [23], as in the case of N 2 2+ , CO 2+ [15], and NO 2+ [16]. This method has two major advantages.…”

Computed lifetimes of metastable states of the NO2+ dication

“…Consequently, the coupling does not seem to play any decisive role in the decays of the states examined. Table I lists the icMRCI vertical transition energies and their experimental counterparts measured by Furuhashi et al 7 using DCT spectroscopy. For the X, A, and B states, our theoretical values are lower by approximately 0.3 eV than the experimental ones.…”

“…By employing Doppler-free kinetic energy release spectroscopy, Edvardsson et al 6 probed the mechanisms behind the dissociation of the B 2 ⌺ + , C 2 ⌺ + , and 2 4 ⌸ states. By utilizing the double charge transfer ͑DCT͒ technique, Furuhashi et al 7 estimated the bond lengths for the X 2 ⌺ + and A 2 ⌸ states and determined the vertical transition energies of the X 2 ⌺ + , A 2 ⌸, B 2 ⌺ + , and 2 ⌸ states. By relying on a smooth variation of the spectral intensities with the vibrational quantum numbers in the time-of-flight photoelectron-photoelectron coincidence ͑TOF-PEPECO͒ spectra, Eland et al 8 reassigned the v = 0 level of the A 2 ⌸ state and confirmed the assignments in the literature for the X 2 ⌺ + and B 2 ⌺ + electronic states.…”