Strong-field-driven dissociation dynamics in CO₂⁺

We theoretically investigated strong-field XUV-IR pump-probe dissociative ionization of CO₂ in full dimensionality by solving in full (3D) dimensionality the coupled-channel Schrödinger equation for the nuclear motion on five coupled Oppenheimer (BO) potential-energy surfaces. Including ab initio calculated non-BO coupling, laser dipole, and spin-orbit couplings calculated using a multi-configurational self-consistent-field quantum-chemistry code, we provide kinetic energy release (KER) spectra for the O(³P_g) + CO⁺( X²Σ⁺) and O⁺(⁴S_u) + CO(X¹Σ⁺) dissociation channels and their branching ratio. Our KER spectra identify the ro-vibrational excitations of CO⁺ fragments along a dominant 3ω dissociation paths. Mediated by the nuclear dynamics near a A²Π_u and B²Σ_u⁺ conical intersection and in good agreement with the experiment of Timmers et al., Phys. Rev. Lett. 113, 113003 (2014), we reproduce a core-hole oscillation period 115 fs. In addition, we find and race as due to quantum beats between specific pairs of vibration and electronic CO₂⁺ states a slower oscillations 62 fs in the CO⁺ fragmentation channel.