Electronic Structure Descriptors for the Adsorption of Aromatic Molecules on Metals

High Resolution Image Download MS PowerPoint Slide The adsorption of aromatic molecules on metallic surfaces is a fundamental process in heterogeneous catalysis, advanced fabrication of semiconductor interconnects, and the design of functional inorganic–organic interfaces. The interaction between adsorbates and metals is governed by a complex interplay of electronic structure, molecular properties, and surface chemistry. Aromatic molecules, due to their tunable electronic and steric properties, exhibit diverse adsorption behavior on metal surfaces, making them ideal candidates for applications requiring precise control over molecule–surface interactions. In this study, we employed Density Functional Theory calculations to screen aromatic molecules with diverse functional groups (e.g., methyl, hydroxyl, amino, and aldehyde) on four transition metal surfaces (Cu, Ru, Mo, and W). While the adsorption on Cu is found to be mainly driven by dispersion forces, strong chemisorption is found on Ru, Mo, and W. Decomposition of the adsorption energies reveals a fundamental trade-off between interaction and distortion contributions, where stronger bonding correlates with greater molecular deformation. Charge analysis reveals electron density displacement toward the π-system of the adsorbate during chemisorption. To rationalize these trends, we integrate d-band center theory with Hard–Soft Acid–Base theory, providing a framework where electronic descriptors explain adsorption strength.