Adatom

An adatom is a single atom that is adsorbed onto a surface. Adsorption is the process by which molecules or atoms stick to the surface of a solid or liquid. Adatoms are important in the study of surface physics and chemistry because they can influence the properties of the surface, such as its reactivity, electronic structure, and catalytic activity. Adatoms can be introduced onto a surface by various means, such as deposition from the gas phase, diffusion from the bulk material, or by chemical reactions on the surface. Adatoms can also migrate on the surface, and their behavior can be studied using techniques such as scanning tunneling microscopy (STM) and atomic force microscopy (AFM).