The Tareq Index (TI): A Novel Graph-Based Descriptor for Inorganic Acids

Topological indices play a significant role in chemical graph theory by providing quantitative measures of molecular structures. Most existing indices are focused on organic compounds, particularly hydrocarbons, with limited applicability to inorganic acids. In this work, we propose a novel graph-theoretical index, the Tareq Index (TI), specifically designed to reflect bonding patterns in inorganic acid molecules. This index incorporates bond multiplicity and molecular connectivity, capturing characteristics often overlooked by traditional indices like the Zagreb or Randić indices. A dataset of over 20 inorganic acids was analyzed, with the TI compared against pKa values and other topological descriptors. Preliminary trends indicate a potential correlation between TI values and acid strength. This contribution offers a new avenue for the structural interpretation of inorganic compounds and lays the foundation for further expansion into quantitative structure–activity/property relationships (QSAR/QSPR) involving inorganic systems.