Title:    The “Charge-Shift Bonding” concept and its manifestation in catalysis

Time:     2025-04-29 10:30

Lecturer:  Prof. Benoît BRAÏDA

Sorbonne Université

Venue:    Room 202, Lu-Jiaxi Building

Abstract：

Valence Bond (VB) theory, since its early derivation by Linus Pauling, has been proved along the years a useful framework for understanding chemical bonding and rationalizing many experimental facts in terms of electronic structure and reactivity of molecules. In the first part of this talk, the three bonding classes emerging from VB theory will be presented, with a special highlight to the more recently proposed “Charge-Shift Bonding” (CSB) family, its physical origin and some of its experimental manifestations, in particular its role in electron-rich hypervalency.

The second part will focus on catalysis, and we will show that Valence Bond Diagrams, a powerful conceptual tool to rationalize trends in reactivity, can reveal the decisive role for secondary coordination sphere nucleophiles on methane C–H activation. A predictive model for methane activation catalysis follows, leading to the proposition that proteins with hydrophobic active sites, available strong nucleophiles, and hydrogen bond donors can be attractive targets for engineering novel methane functionalizing enzymes.