The atom-bond connectivity (ABC) index is a degree-based topological index.It was introduced due to its applications in modeling the properties of certainmolecular structures and has been since extensively studied. In this note, weexamine the influence on the extremal values of the ABC index by various graphparameters. More specifically, we consider the maximum ABC index of connectedgraphs of given order, with fixed independence number, number of pendentvertices, chromatic number and edge-connectivity respectively. We providecharacterizations of extremal structures as well as some conjectures. Numericalanalysis of the extremal values are also presented.
展开▼
