“…This atom type index lends itself to be use in a group additive-type scheme in which an index appears for each atom type in the molecule. In the atom-type bilinear indices formalism, each atom in the molecule is classified into an atom type (fragment), such as -F, -OH, O, -CH 3 , and so on [70][71][72]. Therefore, each atom in the molecule is categorized according to a valence-state classification scheme including the number of attached Hatoms [70].…”