Electronic structure of new donor acceptor substituted chromophores

We have carried out ultraviolet photoelectron spectroscopy (UPS) investigations at a synchrotron source (BESSY I) and quantum chemical calculations in order to study correlations between chemical constitution and electronic structure of a series of conjugated chromophores. Their π-electron system was modified by substitution with different donors and acceptors at terminal positions, by changing the molecular length, by introduction of different conjugated moieties into the central part of the molecules, and by fluorination.