Abstract This contribution examines the interpretation of Graph Derivative Indices (GDIs) from Quantum Mechanics (QM) perspective and its relation with Hückel molecular orbital (HMO) method. The different elements used for calculating Discrete Derivatives over atom-pairs are related to QM integrals appearing in Determinant. between Coulomb Resonance Integrals was estimated by topological way qu...

Structural codes vis-a-vis structural counts, like polynomials of a molecular graph, are important in computing graph-theoretical descriptors which are commonly known as topological indices. These indices are most important for characterizing carbon nanotubes (CNTs). In this paper we have computed Sadhana index (Sd) for phenylenes and their hexagonal squeezes using structural codes (counts). Sa...