Files
Abstract
The ultraviolet photoresistance in biomolecules have been researched extensively in recent years. A bottom-up approach has been applied and the molecular dynamics of heterocyclic rings have raised interest. The presented work here investigates the UV excited state dynamics of five-membered heterocyclic rings imidazole, pyrazole and pyrrole, which are commonly seen as subunits in larger biomolecules. Two nucleo bases that are heterocyclic pyrimidine derivatives uracil and thymine, which are researched less extensively than adenine, are also studied in this work. Time-resolved spectroscopic techniques are applied, including time-resolved photoelectron spectroscopy, time-resolved total kinetic energy release and time-resolved ion yield, all of which are with femtosecond timing resolution which help understanding the ultrafast photoprotection mechanisms. This work can also extend to medical physics such as laser treatment of diseases in the future, as the heterocyclic molecules investigated here are subunits of various corresponding biomolecules.