We propose and test an empirical electrofugality index to rank the leaving group ability of a series of 21 benzhydryl derivatives. The empirical model defines the electrofugality as the negative of the global electrophilicity of the carbocation intermediate in the hydrolysis reaction. The results are in good agreement with the experimental electrofugality scale proposed for the title compounds by Mayr and coworkers [B. Denegri, A. Streiter, S. Juric, A.R. Ofial, O. Kronja, H. Mayr, Chem. Ent. J. 12 (2006) 1648]. (C) 2007 Elsevier B.V. All rights reserved.