STRUCTURAL ANALYSIS OF OCTANE ISOMERS USING GENERALIZED ECCENTRICITY–HARARY INDICES

Abstract

Topological indices are numerical invariants associated with graphs that provide useful information about their structural properties. They have significant applications in chemical graph theory, network analysis, and mathematical modeling, particularly in the study of molecular structures and the prediction of physicochemical properties. In this paper, we present the fundamental concepts of the Harary, Schultz, and Gutman indices and investigate generalized sum, product, and difference-based eccentricity–Harary indices. These indices are applied to the molecular graphs of octane isomers. The basic concepts and structural characteristics of octane isomers are discussed, and the exact values of the generalized sum, product, and difference-based eccentricity–Harary indices are determined for the octane isomers. Furthermore, statistical analysis is performed using SPSS software to examine the predictive ability of the proposed topological indices with respect to selected physicochemical properties of octane isomers. Regression models are developed to identify the most effective topological indices as predictors of the considered physicochemical properties. The results highlight the applicability of the proposed generalized eccentricity–Harary indices in QSPR analysis of octane isomers.