Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Molecules form 2-D patterns never before observed: Nanoscience experiments produce elusive 5-vertex tilings

The 2-D tessellation pattern known as the "semiregular snub square tiling" stands out clearly in this image, which combines scanning tunneling microscopy with computer graphics. The pattern, observed in a surface architecture just one molecule thick, was formed by self-assembly of linear organic linkers, imaged as rods, and lanthanide cerium centers, visualized as bright protrusions. The area shown measures less than 25 nanometers across.

Credit: Barth Lab, copyright TUM
The 2-D tessellation pattern known as the "semiregular snub square tiling" stands out clearly in this image, which combines scanning tunneling microscopy with computer graphics. The pattern, observed in a surface architecture just one molecule thick, was formed by self-assembly of linear organic linkers, imaged as rods, and lanthanide cerium centers, visualized as bright protrusions. The area shown measures less than 25 nanometers across.

Credit: Barth Lab, copyright TUM

Abstract:
Tessellation patterns that have fascinated mathematicians since Johannes Kepler worked out their systematics 400 years ago - and that more recently have caught the eye of both artists and crystallographers - can now be seen in the laboratory. They first took shape on a surface more perfectly two-dimensional than any sheet of writing paper, a single layer of atoms and molecules atop an atomically smooth substrate. Physicists coaxed these so-called Kepler tilings "onto the page" through guided self-assembly of nanostructures.

Molecules form 2-D patterns never before observed: Nanoscience experiments produce elusive 5-vertex tilings

Munich, Germany | Posted on August 8th, 2013

The experiments were carried out by postdoctoral researcher David Ecija, PhD candidate Jose Ignacio Urgel and colleagues in the Physics Department of Technische Universitaet Muenchen (TUM), in collaboration with scientists in Karlsruhe and Zurich. They reported their findings in the Proceedings of the National Academy of Sciences.

Results open a new line of research

Organic molecules equipped with functional groups to express distinct linkages to metal atoms were deposited onto a smooth silver substrate under vacuum conditions. Subsequently the organic layer on this platform was exposed to an atomic flux of the lanthanide cerium. At a certain ratio of cerium atoms to molecules, self-assembly produced a symmetrical complex 2-D pattern described originally by Kepler and known today as the snub square tiling. Clearly identifiable through scanning tunneling microscopy was a recurring, five-vertex connecting element less than one nanometer across, a cerium-ligand coordination unit.

That the snub square tiling pattern had never been fabricated and seen at the molecular level by exploiting self-assembly protocols was interesting in itself. Beyond that, the physicists explain, every new surface architecture could potentially open the way to novel physics and chemistry, and until now five-vertex structures have proven elusive. In particular, the fact that the lanthanide element cerium played such a key role marks this as the beginning of a new line of research.

This is the first time the TUM researchers - members of Prof. Johannes Barth's Institute for Molecular Nanoscience and Chemical Physics of Interfaces - have coordinated molecules with a lanthanide, and the first time anyone has done this in 2-D. "And lanthanides are special," David Ecija explains. "They have very intriguing optical, magnetic, and chemical properties that could be interesting for nanoscience, and possibly also for nanotechnology. Now we have a new playground for research with the lanthanides, and beyond."

This research was supported by the European Research Council through Advanced Grant MolArt (Grant 247299) and Marie Curie Fellowship Grant 274842; the German Research Foundation (DFG) through Grant BA3395/2-1; and the TUM Institute for Advanced Study.

Publication

Five-vertex Archimedean surface tessellation by lanthanide-directed molecular self-assembly. David Ecija, Jose I. Urgel, Anthoula C. Papageorgiou, Sushobhan Joshi, Willi Auwaerter, Ari P. Seitsonen, Svetlana Klyatskaya, Mario Ruben, Sybille Fischer, Saranyan Vijayaraghavan, Joachim Reichert, and Johannes V. Barth. PNAS 2013 Vol. 110 No. 17, pp. 6678-6681. DOI: 10.1073/pnas.1222713110

####

About Technische Universitaet Muenchen
Technische Universitaet Muenchen (TUM) is one of Europe's leading universities. It has roughly 500 professors, 9,000 academic and non-academic staff, and 32,000 students. It focuses on the engineering sciences, natural sciences, life sciences, medicine, and economic sciences. After winning numerous awards, it was selected as an "Excellence University" in 2006 and 2012 by the Science Council (Wissenschaftsrat) and the German Research Foundation (DFG). In both international and national rankings, TUM is rated as one of Germany's top universities. TUM is dedicated to the ideal of a top-level research-oriented entrepreneurial university. The university's global presence includes offices in Beijing (China), Brussels (Belgium), Cairo (Egypt) and Sao Paulo (Brazil). The German Institute of Science and Technology (GIST), founded in 2002 in Singapore, is the first research campus of a German university abroad.

For more information, please click here

Contacts:
David Ecija
Dept. of Physics
Technische Universitaet Muenchen
James-Franck-Str. 1
85748 Munich, Germany
T: +49 89 289 12320
E:
W: http://www.e20.ph.tum.de/

Patrick Regan

49-016-242-79876
Technische Universitaet Muenchen

Copyright © Technische Universitaet Muenchen

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Continuous roll-process technology for transferring and packaging flexible LSI August 29th, 2016

Meteorite impact on a nano scale August 29th, 2016

Designing ultrasound tools with Lego-like proteins August 29th, 2016

A nanoscale wireless communication system via plasmonic antennas: Greater control affords 'in-plane' transmission of waves at or near visible light August 27th, 2016

Govt.-Legislation/Regulation/Funding/Policy

Analog DNA circuit does math in a test tube: DNA computers could one day be programmed to diagnose and treat disease August 25th, 2016

New approach to determining how atoms are arranged in materials August 25th, 2016

Johns Hopkins scientists track metabolic pathways to find drug combination for pancreatic cancer August 25th, 2016

New electrical energy storage material shows its power: Nanomaterial combines attributes of both batteries and supercapacitors August 25th, 2016

Self Assembly

Smarter self-assembly opens new pathways for nanotechnology: Brookhaven Lab scientists discover a way to create billionth-of-a-meter structures that snap together in complex patterns with unprecedented efficiency August 9th, 2016

Magnetic atoms arranged in neat rows: FAU physicists enable one-dimensional atom chains to grow August 5th, 2016

Accurate design of large icosahedral protein nanocages pushes bioengineering boundaries: Scientists used computational methods to build ten large, two-component, co-assembling icosahedral protein complexes the size of small virus coats July 25th, 2016

WSU researchers develop shape-changing 'smart' material: Heat, light stimulate self-assembly July 4th, 2016

Discoveries

Continuous roll-process technology for transferring and packaging flexible LSI August 29th, 2016

Meteorite impact on a nano scale August 29th, 2016

Designing ultrasound tools with Lego-like proteins August 29th, 2016

A promising route to the scalable production of highly crystalline graphene films August 26th, 2016

Announcements

Continuous roll-process technology for transferring and packaging flexible LSI August 29th, 2016

Meteorite impact on a nano scale August 29th, 2016

Designing ultrasound tools with Lego-like proteins August 29th, 2016

A nanoscale wireless communication system via plasmonic antennas: Greater control affords 'in-plane' transmission of waves at or near visible light August 27th, 2016

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

Continuous roll-process technology for transferring and packaging flexible LSI August 29th, 2016

Meteorite impact on a nano scale August 29th, 2016

Designing ultrasound tools with Lego-like proteins August 29th, 2016

A nanoscale wireless communication system via plasmonic antennas: Greater control affords 'in-plane' transmission of waves at or near visible light August 27th, 2016

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic