In the present paper, the possible analytical applications of two topological models, the DARC model and the group contribution model, are discussed. Both models are applied to obtain calibration laws, which relate UV and IR characteristics with the chemical structure of ethylene oxide condensates.The group contribution model is also applied to determine the contribution of each part of the different compounds involved in a chemical interaction process, having established the sensitization parameters of benzodiazepines and anionic surfactants from the micellar enhancement fluorescence. KEY WORDS Topological description of molecules Infrared and ultraviolet spectroscopy Surfactants Benzodiazepines Interaction processes 0886-9383/88/060193-15$07.50