A novel index EDm based on ionicity index matrix, improved distance matrix, and branching degree matrix is used to describe the structural information of the molecule and realizes unique characterization of the molecular structures. The quantitative structure-property relationship (QSPR) models, with correlation coefficients (R) in the range of 0.99-1.00 for standard enthalpy of formation ($Δ fH mθ$), standard entropy ($S mθ$), molar volume (Vm), and molar refraction (Rm) of alkanes, alkenes, and alkynes, are subsequently developed using the...