Lone-pair bonding to surfaces: from water to ammonia and beyond

Here we investigate the surface bonding mechanisms for a group of molecules in which their chemically active molecular orbital is a nitrogen or oxygen 2p lone pair (HOMO). This class includes industrially important molecules including water, alcohols, ethers, ammonia and amines. Using extensive first-principles Density Functional Theory (DFT) modelings, we investigate a large and diverse database of materials from transition metals to oxides, sulfides, nitrides, single sites and beyond. We report universal scaling relations (linear correlations) among the binding energies of lone-pair species and we trace this to the similarities in their electronic structure and similar mechanisms in their bonding to surfaces. We then delve deeper into the details of the lone-pair surface interactions using electronic structure analysis and discover the surface electronic properties that are responsible for dictating the strength of the lone pair-surface bond.