Based on different adjoining method among atoms in molecule, a novel matrix element of incidence matrix was defined and a multi-order index ^pF (^pF′) was put forward. 公式where p stands for the number of bonds from ith to jth bond. ^pF (^pF′) was correlative with every atomic feature, the connectivecases between atoms in molecule. The values of F, ⁰F′, ¹F′ and²F′ were calculated, the linear relationships between F, ⁰F′, ¹F′ or ²F′ and standard formative enthalpies for 144 hydrocarbons including saturated paraffins, unsaturated alkenes and alkylbenzenes were obtained, and the correlation coefficients were larger than 0.98. Also, thecorrelation coefficient between F, ⁰F′ or ¹F′ and standard formative enthalpies for TiX_n (n=1～4, X=F, Cl, Br, I) was above 0.99.

Key words: incidence matrix, hydrocarbon, multi-order index, QSPR