Fig. 3
Neutral excited state dynamics in CH3Br. a Attosecond transient absorption spectroscopy (ATAS) trace corresponding to the neutral excited state dynamics composing process 1. An additional transition, Br (P3/2 → D3/2) (65.4 eV), is predicted to be present, however is obscured in the present experiment due to the ionic absorption features above 65 eV (see Supplementary Note 1 and Supplementary Fig. 2). b A collection of ground, excited, and Rydberg state potential energy curves for CH3Br (computation described in Supplementary Note 3). The bold color curves represent the primary states that compose the excited state band. A conical intersection exists between the 1Q1 and \({^3{Q}_{0^+}}\) excited states that can lead to non-adiabatic population transfer between the two dissociation pathways converging to Br and Br*. c Simulated ATAS dynamics for neutral excited states in CH3Br. From the results of the simulation, we find that the ATAS dynamics are dominated by the \({^3{Q}_{0^+}}\) state, resulting in a dominant Br* atomic yield. A signature of the non-adiabatic transition can be seen as the emergence of Br population at greater time delays in a, c
