Modeling Molar Refraction and Chromatographic Retention by Szeged Indices

Physico-chemical properties, such as the boiling point, molar refraction, critical pressure, viscosity, chromatographic retention, etc. are rather simple experimental available properties of chemical compounds. They are tabulated and may be used e.g., in projecting industrial instalations. Sometimes, it happends that a given compound is toxic, or dangereus or simply not available. In such conditions, it is of interest to have a theoretical tool, say an equation, that can help one in obtaining a desired parameter by structure-related calculations. In this respect, the topological indices (i.e., single numbers encoding the topology of chemical structures) were widely used in the last decade. In the present paper, we used the Szeged indices as molecular descriptors in modeling the molar refraction and the chromatographic retention of some organo-phosphoruc compounds.