On topological coindices and QSPR analysis of silicon carbide networks

Topological coindices analyze topological indices derived from nonadjacent vertex sets to quantify the relationship between a molecular substance and its properties. These indices quantitatively capture molecular topological features and serve as essential tools in developing quantitative structure-property relationships (QSPR) and quantitative structure-activity relationships (QSAR) models. In this article, we propose the Nirmala (N¯), first inverse Nirmala (IN1¯), second inverse Nirmala (IN2¯), geometric-quadratic (GQ¯) and quadratic-geometric (QG¯) coindices for silicon carbide networks, namely SiC3−I[p,q], SiC3−II[p,q] and SiC3−III[p,q], with the aid of their corresponding CoM-polynomials. Additionally, the coindices are numerically calculated and graphically represented to evaluate their behavior. Furthermore, the QSPR analysis is carried out to determine the correlation between the coindices and the cohesive energy of the silicon carbide networks under consideration using curvilinear regression models. Degree-based coindices exhibit a strong correlation with the cohesive energies of the networks.