Determination of the CO3− bond strength via the resonant two-photon photodissociation threshold: Electronic and vibrational spectroscopy of CO3−∙Arn

摘要: We use a two-laser pump-probe technique coupled with messenger atom tagging to determine the bond energy of O− CO2 in CO3− ion, prevalent species upper atmosphere. In this technique, argon-tagged ion is first electronically excited using visible laser, then irradiated tunable near-infrared beam across CO2⋯O− dissociation threshold while products are monitored. This method yields 2.79±0.05eV, which about 0.5eV higher than previously reported. Combining well-known heats formation and CO2, 105.6 −393.1kJ∕mol, respectively [Thermodynamic Properties Individual Substances, edited by L. V. Gurvich, I. Veyts, C. B. Alcock (Hemisphere, New York, 1989), Vol. 1 CODATA Thermodynamic Tables, O. Garvin, Parker, J. H. White 1987)], heat formation: ΔH00=−556.7±4.8kJ∕mol. The one-photon (i.e., linear) infrared electronic spectra also presented and...