Study on the [1 + 1′] photodissociation spectra of via transitions

By preparing CO 2 + ions in the X 2 Π g , 1 / 2 ( 0 0 0 ) state via [3 + 1] multiphoton ionization of CO 2 molecules at 333.06 nm, we have obtained the mass-resolved [1 + 1′] two-photon dissociation spectra of CO 2 + via the C 2 Σ g + ( υ 1 , υ 2 , 0 ) ← B 2 Σ u + ( 0 0 0 ) / A 2 Π u , 1 / 2 ( 0 0 0 ; 1 0 0 ) ← X 2 Π g , 1 / 2 ( 0 0 0 ) transitions by fixing the first dissociation laser at 289.77 nm, 351.24 nm, 337.90 nm to excite the CO 2 + to B 2 Σ u + ( 0 0 0 ) , A 2 Π u , 1 / 2 ( 0 0 0 ) , A 2 Π u , 1 / 2 ( 1 0 0 ) state, separately, and scanning the second dissociation laser in the wavelength range of 557–759 nm. The original CO 2 + ( C 2 Σ g + ( 0 0 0 ) ) position of 45 120 ±3 cm−1 above CO 2 + ( X 2 Π g , 1 / 2 ( 0 0 0 ) ) and the spectroscopic constants of ν 1 = 1400 ± 5 cm - 1 , ν 2 = 620 ± 8 cm - 1 and ν 3 = 2909 cm - 1 for CO 2 + ( C 2 Σ g + ) are deduced from the C 2 Σ g + ( υ 1 , υ 2 , 0 ) ← B 2 Σ u + ( 0 0 0 ) / A 2 Π u , 1 / 2 ( 0 0 0 ; 1 0 0 ) ← X 2 Π g , 1 / 2 ( 0 0 0 ) transition data. The dependence of the product branching ratios [ CO + ] / [ O + ] of CO 2 + ( C 2 Σ g + ) on the vibration levels has been observed and the dissociation dynamics of CO 2 + via C 2 Σ g + state is discussed.