Electromechanically actuating molecules

Controlled motion at the nanoscale is an emerging avenue for low powered electronics. The necessity for precision at the nanoscale makes organic chemistry an exciting addition to electronics, as organic synthesis is based upon the design and creation of nanoscale and sub-nanoscale structures. We have recently demonstrated the role of organic materials in the development of a nanoelectromechanical (NEM) switch that operates by electromechanical modulation of tunneling current through a switching gap defined by a few nanometer-thick organic molecular layer sandwiched between conductive contacts [1]. In this device, the molecular layer not only facilitates controlled formation of nanoscale switching gaps, but also avoids direct contact of the electrodes to minimize surface adhesion and provides force control at the nanoscale to prevent device failure due to stiction. Recent work has focused on the compression of the molecular layer by an applied electrostatic force between the two electrodes to reduce the tunneling gap. However, we envision next generation devices can contain advanced materials, which undergo electrochemically stimulated shape changes to modulate the tunneling distance and current. In order to achieve large current on-off ratios, the molecules must be capable of producing significant changes in dimension or shape upon electrical stimuli. Herein, we report a few examples of electromechanically actuating molecules.