The interfacial chemistry between metal surfaces and molecules plays an important role to an endless list of problems in the physical and chemical sciences. For example, interfacial water is important for heterogeneous ice nucleation on aerosol particles. Interfaces between metals and aromatic molecules are important to tailor the electronic and optical properties of functional materials and organic/inorganic electronic devices. Although the predominant interatomic interactions at these interfaces come from so called chemical bonds, yet much weaker van der Waals (vdW) forces are found to influence the geometry and electronic structures significantly, defying the conventional wisdom. The finding indicates that vdW forces should be accounted for accurately while modeling molecule-metal interfaces. We infer that the heterogeneous ice nucleation—essential for cloud formation—would be a much rare process in the absence of vdW forces. Our study may help in devising materials better suited for artificial cloud formation. Also, weak vdW interactions can be used to tailor hybrid organic/inorganic electronic devices.

References:

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