University of Isfahan Transactions on Combinatorics 2251-8657 13 4 2024 12 01 On topological charge indices of graphs 351 361 27517 10.22108/toc.2023.137285.2062 EN Mohammad Shahryari Department of Mathematics, College of Science, Sultan Qaboos University, Muscat, Oman Gholamreza Vakili-Nezhaad Department of Petroleum and Chemical Engineering, College of Engineering, Sultan Qaboos University, Muscat, Oman Journal Article 2023 04 11 We introduce a fast method of computing the topological charge indices of simple graphs (molecules) which does not require matrices of large sizes. For the case of trees, we give a compact formula and in the general case we obtain upper and lower bounds for the charge indices. We give concrete examples of trees and molecules with their charge indices computed using our method. Topological charge index Valence topological charge index Elegctronegativity Simple garphs graph invariants https://toc.ui.ac.ir/article_27517_8d6b0407a642e3f3320021d2f198c115.pdf