Photochemistry of transition metal complex is of interest to both fundamental chemistry research and applications towards clean energy resources. Photo-initiated C-H activation by transition metal complexes provides a useful tool to clean synthesis and C functionalization. The understanding of the photochemistry and photo-initiated C-H activation gives crucial understanding into the electronic structure changes involved in these processes and helps design more efficient complexes. Here in this proposal, we aim to model the photo-chemistry of transition metal complexes. This includes modelling excited state dissociation pathways, and the energy landscape scape for the reactivity of the photo-products using quantum chemical methods. The spectroscopic signatures with include XAs and RIXS for these species are also to computed and time-resolved XAS/RIXS will be modeled and interpreted against the latest experimentally measurement spectra.