I studied chemistry and physics at the University of Sri Jayewardenepura. In 2009, I was awarded a PhD from the University of Glasgow under the supervision of Prof. John E. McGrady (now in Oxford). Objective of my doctoral dissertation was to use DFT and QM/MM methods to explore the link between the low-lying electronic states of the transition metal clusters and their functions either in reactivity or magnetic properties. My dissertation was examined by Prof. Rob Deeth (University of Warwick). Soon after my graduation, I moved to the University of Oxford as an Engineering and Physical Sciences Research Council (EPSRC) postdoctoral fellow, where I studied magnetic properties of mixed valence open-shell transition metal clusters and biomimetic water oxidation catalysis. In 2010, I was granted a postdoctoral fellowship from the Institute of Chemical Research of Catalonia (ICIQ) to work with Prof. Feliu Maseras. During my stay at ICIQ, I started QM/MM method developments and applications. In 2012, I was awarded a Marie Curie fellowship (LASSIE ER) to continue QM/MM studies with Prof. Gunnar Nyman (Gothenburg University). In 2014, I was granted a Japan Society for the Promotion of Science (JSPS) postdoctoral fellowship to work under the supervision of Prof. Keiji Morokuma (Fukui Institute for Fundamental Chemistry, FIFC). My projects at FIFC were focused on the artificial force induced reaction (AFIR) method. Now I am an assistant professor at Hokkaido University. I develop QM/MM methods and reaction path search approaches to study chemical problems in Organic Chemistry, Inorganic Chemistry, and Astrochemistry. My research projects involve close collaborations with experimental research groups.