Steering Nuclear Motion by Ultrafast Multistate Non Equilibrium Electronic Quantum Dynamics in Atto Excited Molecules

Few-cycle short pulses allow excitation of coherently coupled electronic states towards steering nuclear motions in neutral molecules and cations. The progress of the non stationary vibronic density towards the products can be monitored using a second pulse, by transient absorption spectroscopy or photoionization. The Hamiltonian used to simulate the quantum dynamics includes the pump and probe pulses which provides a quantum mechanical description of both excitation and ionization.