Dipole Formation at Interfaces of Alkanethiolate Self-assembled Monolayers and Ag(111)

Rusu, Paul C. and Giovannetti, Gianluca and Brocks, Geert (2007) Dipole Formation at Interfaces of Alkanethiolate Self-assembled Monolayers and Ag(111). Journal of Physical Chemistry C: Nanomaterials and interfaces, 111 (39). pp. 14448-14456. ISSN 1932-7447

PDF
Restricted to UT campus only: Request a copy
658Kb

Abstract:	The formation of interface dipoles in self-assembled monolayers (SAMs) of −CH3 and −CF3 terminated short-chain alkanethiolates on Ag(111) is studied by means of density functional theory calculations. The interface dipoles are characterized by monitoring the change in the surface work function upon adsorption of the SAM. We compare results obtained for SAMs in structures with a different packing density of molecules, (i.e., (√7×√7)R19.1°, (√3×√3)R30°, and p(2 × 2)). The work function of alkanethiolate SAMs on silver weakly depends on the packing density; that of fluorinated alkanethiolates shows a stronger dependence. The results are analyzed in terms of two nearly independent contributions to the interface dipole. These originate respectively from the molecular dipoles and from a charge transfer between the metal surface and the molecules. The charge transfer is determined by the silver−sulfur bond and it is independent of the electronegativity of the molecules.
Item Type:	Article
Copyright:	© 2007 American Chemical Society
Faculty:	Science and Technology (TNW)
Research Group:	Computational Materials Science (CMS)
Link to this item:	http://purl.utwente.nl/publications/68602
Official URL:	http://dx.doi.org/10.1021/jp073420k
Export this item as:	BibTeX EndNote HTML Citation Reference Manager

Show download statistics for this publication

Repository Staff Only: item control page

Metis ID: 244111