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Department of Chemistry Seminar Series: Martin Rahm, Chalmers University of Technology, Gothenburg, Sweden (Host: Maarten Goesten)

In Situ Electronegativity and the Bridging of Chemical Bonding Concepts

Info about event


Thursday 24 November 2022,  at 15:00 - 17:00


1514-213, Aud I, Department of Chemistry

15.00-15.15:  Coffee & cake
15.15-16:       Talk
16.15-17:       Q&A session for PhD students

This presentation outlines our latest efforts in developing a theoretical framework that connects Molecular Orbital Theory, Quantum Chemical Topology and Energy Decomposition Analysis.[1,2] Central to this theory is a definition of electronegativity as the average energy of valence electrons. This definition runs counter to the electronegativity equalization postulate of Sanderson and allows a perspective in which electronegativities of bonded atoms need not be equal. As chemical potentials equalize in this framework, electronegativities equilibrate. A practical definition of what constitutes an atom in a molecule is introduced, which allows for the quantification of charge, energy and electronegativity in a new way. Utility is demonstrated, with in situ electronegativity shown to be a potent indicator for pKa. Complementarity and comparison with Conceptual Density Functional Theory will be briefly discussed. 

[1] S. Racioppi and M. Rahm, ”In Situ Electronegativity and the Bridging of Chemical Bonding Concepts”, Chem. Eur. J, 27, 18156-18167, 2021

[2] F. Sessa and M. Rahm, “Electronegativity Equilibration”, J. Phys. Chem. A, 126, 5472–5482, 2022