Photoionization and photoelectron spectroscopy of weakly-bound molecular complexes

Many processes relevant to our everyday life depend on some level on intermolecular interactions
between a molecule and its environment. Such interactions govern for example the conformation and
functionality of large biomolecules, determine the energetics of chemical reaction pathways or enable
charge transfer and transport in optoelectronic devices.
Photoelectron spectroscopy of small neutral molecular complexes using extreme ultraviolet radiation
can provide information on intermolecular interactions and allows to study processes enabled by the
environment. At the same time, the small system size allows to avoid negative effects due to the
scattering of photoelectrons that can reduce the level of detail observable in larger environments. In
my talk I will discuss the challenges of such measurements and discuss possible experimental
approaches. Besides general concepts, I will give specific examples of how photoelectron photoion
coincidence spectroscopy can be used to obtain information on selected molecular complexes and
the dynamical processes enabled by the limited molecular environment. In the end I will discuss
possible extensions of this methodology towards time-resolved measurements on weakly-bound
complexes.