Polymetallic Wire Sports Redox Caps

Inorganic chemists at the University of Zurich have synthesized a novel redox-active metal-organic molecular wire that demonstrates long-range electronic communication and could lead to a new mode of data storage (J. Am. Chem. Soc., DOI: 10.1021/ja102570f). Heinz Berke, Koushik Venkatesan, and coworkers created the wire (shown) by starting with a ditungsten butadiyne complex they previously prepared, IL₂W≡C–C≡C–C≡WL₂I, where L is 1,2-bis(diphenylphosphino)ethane. After substituting butadiyne groups for the iodides, they tacked on redox-active iron groups. They find that the conjugated polyyne wires efficiently mediate single-electron conductivity between the iron centers, a distance of more than 24 Å. The team is working with scientists at IBM Research, in Zurich, to incorporate the wires into memory storage devices, Venkatesan notes. The individual wires, when connected between two electrodes, can be reversibly oxidized and reduced by applying a high voltage, he explains. The wire’s oxidized form could potentially store a bit of data; subsequently reducing the wire would erase the bit. Devices made with many wires in parallel could in principle be queried with a low voltage to determine the oxidation state of the wires and read the stored data.