Topological indices of molecular structures are related to certain physicochemical properties, such as the boiling point and stability of molecular structures. Several topological indices have recently been introduced and studies have shown that they are related to certain physical and chemical properties of other molecules. Specifically, Zagreb, atom binding connectivity (ABC), and Sanskruti indices correlate with the degree of branching, enthalpy, and entropy of some organic molecules. In this study, we calculated Zagreb, atomic binding connectivity (ABC) and Sanskruti index (S) for copper (I) oxides and copper (II) oxides CuO. In addition, based on the experimental data, we calculated the unit cell entropy and enthalpy of the two oxides and compared them with atomic binding connectivity and Sanskruti index. It appears that these indicators have a very poor relationship to these physical properties in the oxides of copper, and that they may require some modification to show the considerable compliance reported in other organic molecules."
A graph representing the composition of a molecule and its connectivity is called a molecular graph, and this representation is often called a topological representation of a molecule
Different topological indices are usually used to characterize the correlation between the chemical structure of a molecule and its biological, chemical or physical properties. The applications of different topological indices in Quantitative structure-activity relationship (QSAR) and Quantitative structure-activity relationship (QSPR), virtual screening and computational drug design have been reported
"So far, many different topological indexes have been developed, most of which are just graph descriptors. 8-18 Only a few indicators show their relevance to the biological, chemical or physico-chemical properties of certain molecules. 19 to 21, for example, Zagreb index (M1 and M2) by Gutman and Trinajestic reports, first used in the chemical structure and the correlation of ϖ electronic, however, then the M1 and M2 is related to molecular branching degree.