So there must exist a species with electronic states within this energy range.
This gives you the lifetimes of the various electronic states.
That means it has low energy excited electronic states (like oxygen).
The surface of the semiconductor may reconstruct leading to a new electronic state.
His main research interests lie with the dynamics of molecules in their excited electronic states.
These are molecules which can only exist with one atom in an excited electronic state.
Within each of these electronic states are various vibrational states.
For chemisorption, changes in the electronic states may be detectable by suitable physical means.
Internal conversion is a transition from a higher to a lower electronic state in a molecule or atom.
The photoemission is a useful experimental method for the determination and the study of the electronic states.