A Novel Scalar Index of Molecular Electronegativity Distance-edge Connectivity (Imedc, Λ) Used for Structural Characterization and Expression and Property Estimation and Prediction of Inorganic Compounds
Hu Li · 2002
Chemical structures of various inorganic compounds are expressed by a novel scalar index of molecular distance edge connectivity (Imedc, Λ in short), developed in our laboratory, which consists of the modified MEDC descriptors based on the identical/ pseudo atom. Then quantitative structure property relationships (QSPRs) between the new I MEDC index and the formation heat ( Δ f H θ )of 33 transitional element halides or the crystal energy (lg U ) of 20 alkali metal halides were generated by multiple linear regression method (MLR) through either the modified atomic characteristic delta value δ c i defined physically and the molecular connectivity indexes ( Λ ) expressed mathematically respectively. All (QSPR) models possess high correlation: the correlation coefficients with R =0.956～0.994 respectively. Their modeling correlation capabilities are more advantageous than those obtained by some other methods reported in different literatures. It has been demonstrated that the method possesses the advantages of easy computation, clear significance and convenient application. Then cross validation with leave one out of procedure (CV) are performed and satisfactory results have been obtained with high correlation. The obtained results show that the new index is adapt to characterize chemical structure and to model the physicochemical properties of various inorganic species.