Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study uncovers redox response properties of largest-ever polymeric o-phenylenes

16.11.2010
New findings by researchers at RIKEN and the Japan Science and Technology Agency (JST) have shed light on the remarkable electrochemical response properties of an elusive class of molecular helix structures, charting a new path in the design of molecular machines and devices.

Among the most ubiquitous structural motifs in nature, helices play an essential role in a wide range of biological processes. The capacity of certain helix structures to respond to external stimuli by changing shape, in particular, offers key insights in the design of functional molecular devices. As of yet, however, few such structures have been identified that respond to electrochemical inputs, one of the most important types of stimuli.

Now a class of helical structures has been found to do this, and more. o-Phenylenes are densely-packed chains of phenylene (C6H4) compounds linked together at their ortho positions by heavily-angled connections. Despite potentially rich conformational behavior, o-phenylenes are difficult to study and have been all but forgotten since their discovery more than 50 years ago.

In a paper in Nature Chemistry, the RIKEN/JST research group demonstrates a method for synthesizing polymeric o-phenylenes on scales never before observed, the largest reaching some 48 phenylene units. Problems of electrochemical instability which plagued earlier studies are solved by introducing a nitrogen group to the end of the o-phenylene chain, enabling first-ever exploration of o-phenylene oxidation-reduction response.

Experiments with the new o-phenylenes revealed intriguing results. In solution, the helices depart from their folded form to undergo rapid inversion between clockwise and anti-clockwise orientations, yet when they crystallize, they converge uniformly to only one orientation, in a rare process called chiral symmetry-breaking. Removal of a single electron, meanwhile, converts helices across the entire solution to a more compact form, slowing the inversion rate by a factor of more than 450.

Through its parallel to permanent and long-lasting memory, this unique form of conformational rigidity alterable by electrical inputs offers a completely new design concept for nanotechnology, opening new avenues for the design of molecular wires and other nano-scale devices.

For more information, please contact:

Dr. Takuzo Aida
Functional Soft Matter Research Group
RIKEN Advanced Science Institute
Tel: +81-(0)3-5841-7251 / Fax: +81-(0)3-5841-7310
Ms. Tomoko Ikawa (PI officer)
Global Relations Office
RIKEN
Tel: +81-(0)48-462-1225 / Fax: +81-(0)48-463-3687
Email: koho@riken.jp
Reference:
Eisuke Ohta, Hiroyasu Sato, Shinji Ando, Atsuko Kosaka, Takanori Fukushima, Daisuke Hashizume, Mikio Yamasaki, Kimiko Hasegawa, Azusa Muraoka, Hiroshi Ushiyama and Takuzo Aida. Redox-responsive molecular helices with highly condensed p –clouds. Nature Chemistry (2010). DOI: 10.1038/NCHEM.900

gro-pr | Research asia research news
Further information:
http://www.riken.jp
http://www.researchsea.com

More articles from Life Sciences:

nachricht Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory

nachricht Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Electron highway inside crystal

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...

Im Focus: Significantly more productivity in USP lasers

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:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

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...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

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...

Im Focus: Quantum Particles Form Droplets

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...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>