Depolarization Effects in Self‐Assembled Monolayers: A Quantum‐Chemical Insight
- 15 March 2007
- journal article
- research article
- Published by Wiley in Advanced Functional Materials
- Vol. 17 (7) , 1143-1148
Abstract
Many recent experimental studies have demonstrated that the deposition of a self‐assembled monolayer (SAM) made of polar molecules on a metal surface can significantly modulate its work function and hence the barrier for hole and electron injection in optoelectronic devices. The permanent dipole moment associated with the backbone of the molecules plays a key role in defining the amplitude and direction of the work‐function shift. We illustrate here via quantum‐chemical calculations performed on model systems that the dipole moment of molecules is significantly reduced going from the isolated state to the SAM. Such depolarization effects that are most often neglected thus reduce the work‐function shift and have to be taken in account to control and understand charge‐injection barriers in devices at a quantitative level.Keywords
Funding Information
- Belgian Federal Government (“Interuniversity Attraction Pole in Supramolecular Chemistry and Catalysis, PAI 5/3”)
- European Integrated Project (NAIMO (NMP4-CT-2004-500355))
- Belgian National Fund for Scientific Research
- “Fonds pour la Formation à la Recherche dans L'Industrie et dans L'Agriculture (FRIA)”
This publication has 41 references indexed in Scilit:
- Metal Work-Function Changes Induced by Organic Adsorbates: A Combined Experimental and Theoretical StudyPhysical Review Letters, 2005
- Self-Assembled Monolayers of Thiolates on Metals as a Form of NanotechnologyChemical Reviews, 2005
- Tuning of Metal Work Functions with Self‐Assembled MonolayersAdvanced Materials, 2005
- Diffusion of Na atoms on a Cu(001) surfacePhysical Review B, 1999
- Self-assembled monolayers as interfaces for organic opto-electronic devicesThe European Physical Journal B, 1999
- Controlling charge injection in organic electronic devices using self-assembled monolayersApplied Physics Letters, 1997
- Formation and Structure of Self-Assembled MonolayersChemical Reviews, 1996
- Self-Assembly of Conjugated Molecular Rods: A High-Resolution STM StudyJournal of the American Chemical Society, 1996
- Electronic Structure of Phenylene Vinylene Oligomers: Influence of Donor/Acceptor SubstitutionsThe Journal of Physical Chemistry, 1995
- Theoretical investigation of the electronic and geometric structures and nonlinear optical properties of 2H-pyrrole derivativesJournal of the American Chemical Society, 1991