Both one‐ and two‐color zero kinetic energy‐pulsed field ionization (ZEKE‐PFI) spectra of the first electronically excited state of I+2 (A2Π3/2,u) as well as a new electronic state, the a4Σu state, have been recorded for the first time. In the one‐color (two photon) experiment, transitions to the quartet state are formally spin‐forbidden and this is reflected in the weak transition intensity observed compared with the A2Π3/2,u state. However, in the two‐color (1+2′) experiment, which used the valence B3Π0+u state as an intermediate, transitions into both A2Π3/2,u and a4Σu states are fully allowed and appear in the spectrum with comparable intensity. The a4Σu state appears in the one‐color experiment by virtue of spin–orbit coupling with excited electronic states for which direct ionization from the neutral ground state is fully allowed. Values for ω̄exe of 0.46±0.01 cm−1 for the A2Π3/2,u state and 0.38±0.02 cm−1 for the a4Σu state were derived, together with lower limits for ω̄e of 138±2 and 128±2 cm−1, respectively. In addition, highly vibrationally excited levels of the X2ΠΩ,g state have been probed in the one‐color experiments, by exploiting a propensity for extensive electronic autoionization involving Rydberg states based on the excited X2Π1/2,g and A2ΠΩ,u states as well as the dissociative B2Σ+g state. In the case of the X2Π3/2,g ground state, the vibrational progression extends as far as v+=90 while that associated with the X2Π1/2,g state extends as far as v+=40.

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