IR-UV Spectroscopy of Chromophores with -Systems : and their Clusters in the Gas Phase

Resonance Enhanced Multi Photon Ionization (REMPI) and IR-UV Double Resonance Spectroscopy in molecular beams in combination with Time of Flight mass spectrometry enable the mass and even isomer selective recording of cold UV and IR spectra. By comparing the gained spectra to adapted Quantum chemical calculations, the electronic and geometric structures of molecules, clusters and larger clusters resembling nano-crystallites can be unveiled.