Electrostatic Properties of Ideal and Non-ideal Polar Organic Monolayers: Implications for Electronic Devices


  • We thank Ron Naaman (Weizmann Institute), David Cahen (Weizmann Institute), Dudi Deutsch (Weizmann Institute), and Abraham Nitzan (Tel Aviv University) for many illuminating discussions. Work in Rehovoth was supported by the “Bikura” track of the Israel Science Foundation, the Gerhard Schmidt Minerva Center for Supra-Molecular Architecture, and the historic generosity of the Harold Perlman family. LK holds the Delta Career Development Chair and is an ad personem member of the Lise Meitner Center for Computational Chemistry. HH holds the Horev Chair for Leaders in Science and Technology and acknowledges a Marie Curie Excellence Grant of the EC's FP6 and the Russell Berrie Nanotechnology Institute for support. RTT gratefully acknowledges financial support from the National Science Foundation (DMR-0706138). HH and RTT also thank the US-Israel Binational Science Foundation for financial support.


Molecules in (or as) electronic devices are attractive because the variety and flexibility inherent in organic chemistry can be harnessed towards a systematic design of electrical properties. Specifically, monolayers of polar molecules introduce a net dipole, which controls surface and interface barriers and enables chemical sensing via dipole modification. Due to the long range of electrostatic phenomena, polar monolayer properties are determined not only by the type of molecules and/or bonding configuration to the substrate, but also by size, (dis-)order, and adsorption patterns within the monolayer. Thus, a comprehensive understanding of polar monolayer characteristics and their influence on electronic devices requires an approach that transcends typical chemical designs, i.e., one that incorporates long-range effects, in addition to short-range effects due to local chemistry. We review and explain the main uses of polar organic monolayers in shaping electronic device properties, with an emphasis on long-range cooperative effects and on the differences between electrical properties of uniform and non-uniform monolayers.