Modification of Wiener Index and its application

Area of Science:

• Chemical Informatics
• Computational Chemistry
• Quantitative Structure-Property Relationships (QSPR)

Background:

• The Wiener Index is a well-established topological descriptor for molecular graphs.
• Existing topological indices may not fully capture the complexities of heteroatom-containing and multiple bond systems.
• Accurate prediction of molecular properties is crucial for drug discovery and materials science.

Purpose of the Study:

• To introduce a novel topological index, W*, based on the Wiener Index.
• To incorporate atomic properties like electronegativity and atomic number into the index definition.
• To assess the applicability and predictive power of W* for various chemical compounds.

Main Methods:

• Definition of W* incorporating electronegativity (I), bond length (R), and atomic numbers (Z).
• Calculation of S*(ij) for adjacent and non-adjacent atoms, considering electronegativity and atomic number ratios (alpha).
• Application of W* to predict gas chromatography retention index and standard formation enthalpy.

Main Results:

• The proposed W* index effectively accounts for vertex properties and interactions within molecules.
• W* demonstrates applicability to heteroatom-containing organic systems, multiple bond systems, and inorganic compounds.
• High correlation coefficients (above 0.97) were achieved in predicting retention index and formation enthalpy for hydrocarbons, methyl halides, halogen-silicon, and transition metal compounds.

Conclusions:

• The novel W* topological index offers a robust method for predicting molecular properties.
• W* provides a valuable tool for quantitative structure-property relationship studies.
• This index shows significant promise for applications in diverse areas of chemistry and materials science.