molecular ions*

We study the ultrafast photodissociation of small diatomic molecules using attosecond laser pulses of moderate intensity in the XUV regime. The simultaneous application of subfemtosecond laser pulses with different photon energies - resonant in the region of the molecular motion - allows one to monitor the vibrational dynamics of fast diatomics, like the D2+ and HeH+ molecular ions (Biró and Csehi, accepted in J. Phys. Chem. A). In our real-time wave packet simulations, the nuclear dynamics is initiated either by sudden ionization (D2+) or by explicit pump pulses (HeH+) via distortion of the potential energy of the molecule. The application of time-delayed attosecond pulses leads to the breakup of the molecules. The information on the underlying bound-state dynamics is imprinted in the kinetic energy release (KER) spectra of the outgoing fragments (Phys. Chem. Chem. Phys. 24, 13234, 2022). We show that the KER-delay spectrograms generated in our ultrafast pump-probe schemes are able to reconstruct the most important features of the molecular motion within a given electronic state, such as the time period or amplitude of oscillations, interference patterns, or the revival and splitting of the nuclear wave packet.