Spin-Orbit Interactions in Ultrafast Molecular Processes

International audience; We investigate spin-orbit interactions in ultrafast molecular processes employing the exact factor-ization of the electron-nuclear wavefunction. We revisit the original derivation by including spin-orbitcoupling, and show how the dynamics driven by the time-dependent potential energy surface allevi-ates inconsistencies arising from different electronic representations. We propose a novel trajectory-based scheme to simulate spin-forbidden non-radiative processes, and we show its performance inthe treatment of excited-state dynamics where spin-orbit effects couple different spin multiplets