  Photoinduced quantum dynamics in molecules have hierarchical temporal
structures with different energy scales that are associated with electron and
nuclear motions. Femtosecond-to-attosecond transient absorption spectroscopy
(TAS) using high-harmonic generation (HHG) with a photon energy below 300 eV
has been a powerful tool to observe such electron and nuclear dynamics in a
table-top manner. However, comprehensive measurements of the electronic,
vibrational, and rotational molecular dynamics have not yet been achieved.
Here, we demonstrate HHG-based TAS at the nitrogen K-edge (400 eV) for the
first time, and observe all the electronic, vibrational, and rotational degrees
of freedom in a nitric oxide molecule at attosecond to sub-picosecond time
scales. This method of employing core-to-valence transitions offers an
all-optical approach to reveal complete molecular dynamics in photochemical
reactions with element and electronic state specificity.
