Photoluminescence properties of new BF2 complexes with pyrazolone ligands: Dependence on volume and electronic effect of substituents
摘要:
Novel fluorine-boron complexes with donor-acceptor architecture in which pyrazoline-1,3-diones were chosen as electron donors have been synthesized and well characterized. Correlation of the luminescence properties of the complex 2c and its crystal structures was discussed. Well-ordered molecular packing in the crystal results in strong charge transfer interactions characterized by long excited-state lifetime. These fluorine-boron complexes show photophysical properties highly dependent on the solvent polarity and aggregation states. The substituents on the pyrazoline were found to have a significant impact on the solid-state luminescent properties. As a result, some significant differences in charge transfer modes were observed in the solid state among these complexes. (C) 2010 Elsevier B.V. All rights reserved.