Chemical bonding at surfaces and interfaces: a unifying concept in heterogeneous catalysis

Abstract The phenomena occurring at interfaces are complex, and elucidating their influence on catalytic performance remains a major challenge. Among the many physicochemical processes active at surfaces and interfaces, the formation and evolution of chemical bonds during catalytic reactions constitute a fundamental aspect of catalytic function. Here, we briefly revisit established models of chemical bonding, which include Dewar–Chatt–Duncanson (DCD), Blyholder, Newns–Anderson and the d-band models, together with real-space density-based frameworks such as atoms in molecules (AIM) and the electron localization function (ELF). We highlight their latest applications in experimental and theoretical studies, demonstrating their continued relevance. We then outline illustrative examples of emerging directions in this area. While the contributions in this special issue span a broad spectrum of topics within surface and interface science, this introductory article provides a unifying conceptual foundation that complements the diverse studies showcased. This article is part of the theme issue ‘Surfaces, interfaces and heterogeneous catalysis’.