Licenciate Thesis defense: A theoretical perspective on photoinduced reactions - based on quantum chemical models and non-adiabatic molecular dynamics

The wide application arrays for photochemical reactions are the result of light-matter interaction at the electronic level. The diverse utilization of photochemistry across various fields, such as photovoltaic materials, molecular switches, and biological systems relies on the electronic and structural transformations induced by photoexcitation as well as the molecular alteration due to electron and charge transfer. An improved understanding of these photochemical events is dependent on the fundamental theoretical evaluations, to model and analyze the ultrafast processes. The studies discussed in this thesis explore such theoretical implementation in two different frontiers.

In the first study, dynamic simulations are performed to model the light-induced bond dissociation of phenyl azide. The surface hopping formalism, implemented under the semiclassical molecular dynamics approach helped in tracing the time evolution of the electronic and structural levels, involved in the photodissociation. In the second study, the time-dependent density functional theory has been applied to generate XA spectra of imidazole solutions. The theoretical assessments support experimental measurements and provide more insight into the core excitations and structural influence on the absorption spectra.