In the last decade, several studies investigated the excited-state dynamics of SO 2 , showing that intersystem crossing plays a crucial role. Moreover, its conical intersection between the two lowest singlet excited states, 1 1 A 2 and 1 1 B 1 has been studied in detail. Excitation from the ground-state to the 1 1 B 1 state is a dipole allowed transition, which corresponds to the S 0 to S 1 excitation at the Franck-Condon position. It has been shown that an excitation to the 1 1 B 1 state leads to small intermediate population transfer to S 2 , but most of the population stays in the S 1 state throughout the simulation. Since we use the system and its S 1 /S 2 conical intersection as a proof-of-principle example for the energy-only approach, trajectories are initially located on the S 2 state. This allows to study a large population transfer from the S 2 to the S 1 state within 100 fs. Corresponding results for trajectories starting from the S 1 state are given in the SI.