Theory of strong-field ionization of alignedCO2

Abstract

A theoretical framework for studying strong-field ionization of aligned molecules is presented, and alignment-dependent ionization yields are computed for ${\text{CO}}_{2}$. Our calculations are in unprecedented agreement with recent experiments. We find that the ionization process is affected by intermediate resonance states, and the alignment-dependent ionization yields do not follow the electron density of the initial states. The theory explains the breakdown of semianalytical theories, such as the molecular tunneling theory and strong-field approximation, where excited electronic structure is neglected.