Molecular Engineering of the Polarity and Interactions of Molecular Electronic Switches

• Published in: Journal of the American Chemical Society 2005-12, Vol.127 (49), p.17421-17426
• Main Authors: Lewis, Penelope A, Inman, Christina E, Maya, Francisco, Tour, James M, Hutchison, James E, Weiss, Paul S
• Format: Article
• Language: English
• Subjects: Applied sciences; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electrical properties of specific thin films; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronics; Exact sciences and technology; Molecular electronics, nanoelectronics; Physics; Polymers; organic compounds; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/ja055787d

We have investigated and learned to control switching of oligo(phenylene ethynylene)s embedded in amide-containing alkanethiol self-assembled monolayers on Au{111}. We demonstrate bias-dependent switching of the oligo(phenylene ethynylene)s as a function of the interaction between the dipole moment of the oligo(phenylene ethynylene)s and the electric field applied between the scanning tunneling microscope tip and the substrate. We are able to invert the polarity of the switches by altering their designinverting their dipole moments. For appropriately designed switches and matrix molecules, the conductance states are stabilized by intermolecular hydrogen bonding. These results further support the hypothesis that conductance switching in these molecules is due to hybridization changes at the molecule−substrate bonds due to tilting of the switch molecules.