New fluorene based tetramers for luminescence applications

Fluorene based polymers have been receiving much attention as promising component in luminescence devices. In this frame the related oligomers reached relevance either as polymeric models or as active layers. On these basis, three fluorenic-core tetramers have been synthetized via organosynthetic routes. The molecular, optical and electrochemical characterization of such oligomers in solution has been performed, furthermore, their high photoluminescence quantum yields (PLQY) render them attractive for electroluminescent device preparations. In this view the optical investigations with both absorption and emission techniques were also carried out in the solid state samples in thin films (up to 80 nm thick) obtained by solution casting or evaporation using ultra high vacuum apparatus. Detailed structural analyses from XRD data allowed packing determination, hence the optical properties are related to the different type of aggregation in the solid state.