Charge transfer energies of the complexes of (dibenzoylmethanato)boron difluoride with indeno-pyridines and polynuclear aromatic hydrocarbons

Charge transfer complexes of electron deficient (dibenzoylmethanato)boron difluoride (DBMBF2) with polyaromatic hydrocarbons (A), as well as with highly electron rich indeno-pyridines (I) compounds in ethanol medium have been studied by electronic absorption spectroscopy. Absorption band due to a charge-transfer (CT) transitions are observed in the visible region. Utilizing the CT transition energy, the vertical electron affinities (E-A(v)) of DBMBF2 in ethanol has been calculated. The value of EX for DBMBF2 is found to be 2.28 eV, this is the first report of its electron affinity value. We have calculated the degrees of CT and transition dipole strengths of the DBMBF2/A and DBMBF2/I complexes. Along with both theoretically calculated and experimentally obtained vertical ionization potentials of the indeno-pyridine donors have been estimated for the first time. I show high degree of charge transfer along with high ground state stability similar to that of A. Thus indeno-pyridine (I) donors are also as good as aromatic hydrocarbons (A) for DBMBF2, having equivalent ionization potential like that of aromatic hydrocarbons. (C) 2013 Elsevier B.V. All rights reserved.