To improve the understanding of the formation of electron donor-acceptor complexes of [60]- and [70]fullerenes, EDA interaction of [60]- and [70]fullerenes and some other electron acceptors with benzoyl acetone were studied in CHCl3 medium using absorption spectrophotometry. An absorption band due to charge transfer (CT) transition is observed in the visible region. The vertical ionization potential (I-B(v)) of the benzoyl acetone was determined from the CT transition energy. Oscillator and transition dipole strengths have also been calculated. Trends in the formation constant for the complexes [60]- and [70]fullerenes with benzoyl acetone were discussed in terms of enthalpies and entropies of formation. (C) 2004 Elsevier B.V. All rights reserved.