The HMO method, which describes the variation of bond energies of two-center, two-electron bonds AB with an electronegativity difference Deltachi by a hyperbolic relationship, is investigated and suggests that the bond energies of triangular three-center, two-electron bonds of the type AB, are described by a similar hyperbolic relationship that is displaced alone, the Deltachi axis by the resonance integral beta(BB). The mutual relationship of these idealized bond-energy/electronegativity difference curves provides a basis for rationalizing the observed influence of electronegativity on reactions involving three-center bonds in the gas and liquid phases. Using this analysis, the contribution of the B-B interaction to the strength of a three-center bond AB(2) can be dissected into two discrete components. These are (i) the extra "aromatic" energy due to cyclic conjugation of two electrons and (ii) a contribution that is determined by the electronegativity difference Deltachi (proportional to the difference in the Coulomb integrals, i.e., alpha(A) - alpha(B) = h) and by the resonance integral BB for the B-B interaction. We refer to the second contribution, which can be positive or negative depending upon the value of h, as the -2hbeta effect, as it is this term that characterizes the second contribution in the bond-energy equations.