The binding energies of oxygen 1s electrons, measured by X-ray photoelectron spectroscopy and calculated by quantum-chemical methods were analyzed. The example of twelve series of oxygen-containing compounds was used to show for the first time that electron-deficient systems of three types (O-centered radical cations formed by release of an inner or a valent electron and H-complexes of the PhO-H…O type) h a common feature. In all the systems, the effect of substituents on the reaction centers combines of the inductive, resonance, and polarization effects.