That means it has low energy excited electronic states (like oxygen).

Surface states are electronic states found at the surface of materials.

So there must exist a species with electronic states within this energy range.

Within each of these electronic states are various vibrational states.

His main research interests lie with the dynamics of molecules in their excited electronic states.

The surface of the semiconductor may reconstruct leading to a new electronic state.

Internal conversion is a transition from a higher to a lower electronic state in a molecule or atom.

These are molecules which can only exist with one atom in an excited electronic state.

For chemisorption, changes in the electronic states may be detectable by suitable physical means.

This gives you the lifetimes of the various electronic states.