van der Waals (vdW) interaction plays a fundamental role in the surface-molecules related phenomena. Tuning of the correlated charge fluctuation in the vdW complex is a plausible way to modulate the molecules interaction at the atomic surface. We report vdW interaction tunability of the graphene-CO2 complex by combining the first principle calculations with the vdW exchange correlation density functionals and the time evaluation measurements of CO2 molecules adsorption/desorption on graphene under an external electric field. The field-dependent charge transfer within the complex unveils the controllable tuning of CO2 from acceptor to donor. Meanwhile the configuration of the adsorbed molecule - the equilibrium distance from graphene and O-C-O bonding angle - is modified accordingly. The range of electrical tunability is a unique feature for each type of molecules.
@article{arxiv.1507.01680,
title = {Observation of Electrically Tunable van der Waals Interaction in Graphene-Molecule Complex},
author = {Manoharan Muruganathan and Jian Sun and Tomonori Imamura and Hiroshi Mizuta},
journal= {arXiv preprint arXiv:1507.01680},
year = {2016}
}