Abstract: In this work, the adjacency matrices of molecules are extended. The extended matrices are defined as EA matrices. Two new topological indexes based on the eigenvalues of the EA matrices are EAΣ and EAmax. EAΣ is the sum of the absolute eigenvalues of the EA matrices, and EAmax is the maximum of the absolute eigenvalues of the EA matrices EAΣ and EAmax are called EA Seriers Indexes(EASI). Research shows that EASI are highly discriminating and well correlated with some physicochemical properties of organic compounds.

Key words: QSPR, topological index, molecular structure