State-to-state photodissociation dynamics of the water molecule

Photodissociation provides an ideal proving ground for an in-depth understanding of the microscopic mechanism and dynamics of bond breaking processes at a state-to-state level. After a brief outline of the requisite theory, we review the latest developments on the state-to-state photodissociation dynamics of the water molecule via the lowest two excited states, focusing on the absorption spectrum and product state distributions. A detailed discussion is given on the competition between different adiabatic and nonadiabatic pathways of the dissociation. Quantum mechanical studies of this prototypical system on accurate coupled potential energy surfaces not only offer an interpretation of the existing experimental results but also provide a clear and comprehensive dynamical picture of water photodissociation. (C) 2017 Wiley Periodicals, Inc.