In the burgeoning field of nano-science there are now many ways of 'writing' molecular-scale messages on a surface, one molecule at a time. The trouble is that writing a molecule at a time takes a very long time.
"It is much better if the molecules can be persuaded to gather together and imprint an entire pattern simultaneously, by themselves. One such pattern is an indefinitely long line, which can then provide the basis for the ultimately thin molecular 'wire' required for nano-circuitry," says John Polanyi of the University of Toronto's Department of Chemistry, co- author of the paper to be published on Nature Chemistry this week.
The paper describes, for the first time, a simple molecule that each time it chemically reacts with a surface prepares a hospitable neighbouring site at which the next incoming molecule reacts. Accordingly, these molecules, when simply dosed (blindly) on the surface, spontaneously grow durable 'molecular-chains'. These molecular chains are the desired prototypes of nano-wires.
The experiments were conducted by graduate student Tingbin Lim in the John Polanyi Scanning Tunneling Microscopy laboratory at U of T, in conjunction with theory performed by postdoctoral fellow Dr. Wei Ji in the Hong Guo laboratory in the Department of Physics, McGill University. The experiments in Toronto yielded visual evidence of the chains, and the theory at McGill explained why the chains spontaneously grew.
"Early-on, far-sighted Xerox Research Centre Canada (XRCC) recognized this opportunity for imprinting patterns at the molecular scale, thereby persuading Ontario Centres of Excellence (OCE) and the federal Natural Sciences and Engineering Research Council (NSERC), through its Strategic Grant program, to fund the bulk of the research costs in our lab," says Polanyi.
"The experiments constituted the doctoral work of a recent PhD student in the Toronto laboratory, Dr. Tingbin Lim an outstanding student who came from Singapore to join our group and now makes his home as a scientist in Canada."
Dr. Wei Ji who did much of the calculations at McGill has returned to his native China where he has been appointed a full Professor. He remains in close collaborative touch with his colleagues at McGill and also in Toronto, to the benefit of all three locales.
The paper, entitled "Surface-mediated chain reaction through dissociative attachment" will be published on Nature Chemistry's website on December 12 at 1 pm Eastern time.
Authors are John C. Polanyi and Tingbin Lim of U of T's Department of Chemistry and Institute of Optical Science and Jong Guo and Wei Ji of the Centre for the Physics of Materials and the Department of Physics, McGill University.
The research was supported by the NSERC, Photonics Research Ontario (PRO), an Ontario Centre of Excellence (OCE), the Canadian Institute for Photonic Innovation (CIPI), the Xerox Research Centre Canada (XRCC), Fonds de Recherche sur la Nature et les Technologies (FQRNT) of Quebec and the Canadian Institute for Advanced Research (CIFAR).
Kim Luke | EurekAlert!
Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory
Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine