Time-dependent GW molecular dynamics for an accurate mechanistic description of the dynamics of chemical reactions*

The applicability of the adiabatic local density approximation (ALDA) exchange-correlation kernel, which is always used in real-time time-dependent density functional molecular dynamics simulations, is questionable as it is not valid for any system which is initially in its excited state such as in photochemical reactions. Another problem of the local density approximation is that each one-electron level does not reflect the correct total energy of the corresponding Born-Oppenheimer surface. Extended quasiparticle theory (EQPT) has been shown to completely solve this problem. It guarantees the applicability of the GW approximation to any excited eigenstate as the initial reference state, contrary to conventional wisdom in the GW community. We have developed for the first time, excited-state nonadiabatic time-dependent GW molecular dynamics (ES-NA-TDGW-MD, or TDGW in short) on the basis of EQPT to overcome the problem of ALDA for ES dynamics. It is the only method that can accurately probe the reaction dynamics with exactly satisfying extended Koopmans’ theorem. In this talk, I will demonstrate how the dynamics of methane photolysis with(out) the Ni catalyst is accurately captured using TDGW and discuss future directions of our novel method.