Imaging of direct photodetachment and autodetachment of (OCS)₂^-: Excited-state dynamics of the covalent dimer anion

Ion clusters are excellent vehicles for the study of the transition between the gas-phase and bulk properties of matter as they allow examination of molecular ensembles under well-defined conditions. Thus, photoelectron imaging experiments in which both the molecular and "bulk" properties are manifest in the excitation of a small disintegrating anion is reported. The results show that th applicability of the bulk description to such a highly dynamic system is dependent on the electronic structure, particularly the availability of low-lying excited states.