[en] In an attempt to rationalize and improve an approximate exchange perturbation scheme related to the model of Murrell et al., more accurate approximations are introduced eliminating the use of empirical parameters. The total interaction energy was evaluated as the sum of additive electrostatic, exchange, charge transfer, and dispersion contributions. It is proven that the assumption of intramolecular ZDO approximation is equivalent to the use of the Mulliken formula for intermolecular integrals in the region of small overlap. It is also shown that the use of exact two-center resonance integrals and atomic multipole expansion leads to a substantial improvement of results. The method was applied to calculation of interaction energies of some model hydrogen-bonded complexes of water, hydrogen, fluoride, adenine, thymine, guanine, and cytosine using approximate all-valence wave functions. 42 references