The electronic structure of the ozone molecule (O3) from core to
valence is strongly interrelated with its molecular dynamics, leading
to a flexibility but also to a sensitivity to destructive influence.
It is well know that the electronic structure of O3 is extremely
complicated compared to other three-atomic molecules. With help of
synchrotron-radiation studies and ab-initio calculations we could
observe and explain a wide range of phenomena related to the excitation
and dissociation of O3. Focusing on core-hole states, we found
electronic configuration and molecular geometry highly correlated.
Those results certainly are of general interest to the chemistry
community. On the other hand, our investigations serve as a model for
highly correlated atomic systems.
In my talk I will focus on two results of that major study. Core
ionization was studied with electron spectroscopy using synchrotron
radiation. The induced nuclear dynamics observed are inherently
different for ionization of the central and the terminal oxygen site.
Ab-initio MRCI computations of the electronic configurations for the
two core-ionized states explain the nuclear dynamics in terms of
dynamical changes in the dominant electronic configuration. Another
effect of this correlation was found in Resonant Auger Spectroscopy
(RAE) experiments. A symmetry break in core-excitation probability was
observed. It is explained with vibronic coupling between two
core-excited states that leads to localization of the excitation to one
of the two chemical bonds. This result verifies the localized picture
of core excitation in large molecular systems, even with
symmetry-equivalent sites involved.