Doubly ionised 2,4-imidazolidinedione (hydantoin) dissociations induced by electron collision, fragmentation thresholds vs. vertical excitation energies

Abstract

The double ionisation/dissociation process for a prebiotic molecule (hydantoin) induced by 20–40 eV electron collisions was studied using time-of-flight spectrometry and velocity map imaging. Fragmentation into two molecular cations reveals that hydrogen transfer occurs in the excited state. Furthermore, the thresholds of the main dissociation channels were measured. Comparison with state-of-the-art calculations of the vertical excited states of hydantoin²⁺ gives an accurate indication of the initial population of the excited states.