Fragmentation of hydrated thymine clusters in the gas phase by the interaction with UV photons

Fragmentation of hydrated thymine clusters in the gas phase induced by a UV laser pulse at 266 nm was studied by means of time-of-flight mass spectrometry. The range of laser intensity for the interaction of the clusters was from 107 to 109 W/cm2. In the laser intensity region of 107–108 W/cm2, the hydrated fragment ions derived from hydrated thymine clusters were detected due to C–C and C–N bond breaks in ring structure of thymine. The fragmentation mechanism of hydrated thymine clusters was inferred from molecular dynamics and molecular orbital simulations for a photoionized hydrated thymine cluster model.