Electron attachment in the field of the ground and excited electronic states of the azulene molecule

Azulene attaches thermal and near-thermal energy electrons forming a long-lived parent negative ion in the field of the ground state with a mean autoionization lifetime of 7±1.5 μsec and a mean thermal attachment cross section of 3.5X10^-15cm². The cross section for the thermal process is sharp. Evidence is presented also for electron attachment in the field of a low-lying excited electronic state (possibly the lowest x-triplet state) of azulene in addition to the thermal (∼0.0-eV) process. Using the present values of the thermal attachment rate and lifetime, the electron affinity of azulene in the ground state is estimated to be ≥0.46eV.