Photodissociation Dynamics of Carbon Dioxide Cation via the Vibrationally Mediated òΠ_u,1/2 State: A Time-Sliced Velocity-Mapped Ion Imaging Study

We report on the photodissociation dynamics of CO₂⁺ via its òΠ_u,1/2 state using the scheme of 1+1 photon excitation that is intermediated by the mode-selected òΠ_u,1/2( u1,u2,0) vibronic states. Photodissociation fragment exciation spectrum and images of photofragment CO⁺ have been measured to obtain reaction dynamics parameters such as the available energy and the average translational energy. Combining with the potential energy functions of CO₂⁺, the dissociation mechanism of CO₂⁺ is discussed. The conformational variation of CO₂⁺ from linear to bent on the photodissociation dynamics of CO₂⁺ is verified.