<< The researchers found that weak long-range van der Waals (attractive or repulsive forces between molecules or atomic groups that do not arise from interactions due to a covalent bond or electrostatic force) yielded the largest contribution to the molecule-surface interaction >>
A self-assembling molecular nanoswitch
A possible future molecular memory device. January 18, 2016
http://www.kurzweilai.net/a-self-assembling-molecular-nanoswitch
<< We find that on both substrates, the adsorbate-substrate interaction is dominated by attractive van der Waals forces >>
Moritz Müller, Katharina Diller, et al. Interfacial charge rearrangement and intermolecular interactions: Density-functional theory study of free-base porphine adsorbed on Ag(111) and Cu(111). The Journal of Chemical Physics, 2016; 144 (2): 024701 DOI: 10.1063/1.4938259 (open access)
http://scitation.aip.org/content/aip/journal/jcp/144/2/10.1063/1.4938259