Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > An Odd Couple

Abstract:
Photoluminescent liquid crystals based on metal clusters

An Odd Couple

Weinheim, Germany | Posted on April 30th, 2010

Combine liquid crystals (mesogens) and metal clusters and you get clustomesogens -- a new class of compounds, the first examples of which have now been produced by scientists at the Universities of Rennes (France) and Bucharest (Rumania). As the team headed by Yann Molard and Stephane Cordier reports in the journal Angewandte Chemie, when irradiated, the material glows intensely in the red and infrared range.

Liquid crystals are familiar from LC displays. These materials behave like something between a liquid and a solid. On one hand, their molecules are oriented and partially ordered like in a crystal; on the other, they are not rigid, but truly mobile, like in a liquid. When a voltage is applied, liquid crystals can be switched between different states.

Another class of materials of interest to the optoelectronics field is metal clusters. Clusters are aggregates of a few atoms. Such clusters of metal atoms show unusual electronic, magnetic, and optical properties that arise from the metal-metal bonds in the cluster, and the properties are completely different from those of macroscopic metal particles. The team was able to unite the interesting characteristics of both types of material in the form of a new class of materials called clustomesogens, which contain metal clusters in a liquid-crystalline phase.

Liquid crystals with metal-metal bonds have been rare and limited to species with only two connected metal atoms. The scientists have now constructed a liquid crystal that contains octahedral clusters made of six molybdenum atoms. For stabilization, there are eight bromide ions coordinated as ligands above the eight surfaces of the octahedron. The researchers attached special organic ligands to the six corners of the octahedron. These ligands are aromatic rings, each equipped with three long hydrocarbon chains, the ends of which are also made of two aromatic rings. Simple warming triggers a self-organization process by which the clusters stretch out to form long, narrow units (see figure) arranged in a lamellar structure. The flat rings at the ends of the ligands of neighboring layers are interleaved; this structure has liquid-crystalline properties.

The material shows strong luminescence in the red/near infrared range when excited over a broad range of wavelengths, and this type of material may be useful for the production of red displays and infrared signals. The new class of compounds has been patented in the USA in November 2009 as no. 61/264888.

Author: Yann Molard, Université de Rennes 1 (France),
scienceschimiques.univ-rennes1.fr/csm/personnel/y_molard.html

Title: Clustomesogens: Liquid Crystal Materials Containing Transition-Metal Clusters

Angewandte Chemie International Edition 2010, 49, No. 19, 3351-3355, Permalink to the article: dx.doi.org/10.1002/anie.201000325

####

About Wiley InterScience
Wiley InterScience (www.interscience.wiley.com) provides access to over 3 million articles across nearly 1500 journals and 7000 Online Books and major reference works. It also holds industry leading databases such as The Cochrane Library, chemistry databases and the acclaimed Current Protocols laboratory manuals.

Wiley InterScience is one of the world's premiere resources for study, teaching and advanced research.

For more information, please click here

Contacts:
Editorial office


Amy Molnar (US)


Jennifer Beal (UK)


Alina Boey (Asia)

Copyright © Wiley InterScience

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

SEMATECH to Showcase Innovation and Advances in Manufacturing at SEMICON Japan 2014: SEMATECH experts will share the latest techniques, emerging trends and best practices in advanced manufacturing strategies and methodologies November 26th, 2014

Australian startup creates world’s first 100% cotton hydrophobic T-Shirts November 26th, 2014

The mysterious 'action at a distance' between liquid containers November 26th, 2014

'Giant' charge density disturbances discovered in nanomaterials: Juelich researchers amplify Friedel oscillations in thin metallic films November 26th, 2014

Display technology/LEDs/SS Lighting/OLEDs

Spiraling light, nanoparticles and insights into life’s structure November 19th, 2014

Strengthening thin-film bonds with ultrafast data collection October 23rd, 2014

QD Vision Wins Prestigious Presidential Green Chemistry Challenge Award from the U.S. Environmental Protection Agency October 16th, 2014

Beyond LEDs: Brighter, new energy-saving flat panel lights based on carbon nanotubes - Planar light source using a phosphor screen with highly crystalline single-walled carbon nanotubes (SWCNTs) as field emitters demonstrates its potential for energy-efficient lighting device October 14th, 2014

Possible Futures

A novel method for identifying the body’s ‘noisiest’ networks November 19th, 2014

Researchers discern the shapes of high-order Brownian motions November 17th, 2014

VDMA Electronics Production Equipment: Growth track for 2014 and 2015 confirmed: Business climate survey shows robust industry sector November 14th, 2014

Open Materials Development Will Be Key for HP's Success in 3D Printing: HP can make a big splash in 3D printing, but it needs to shore up technology claims and avoid the temptation of the razor/razor blade business model in order to flourish November 11th, 2014

Materials/Metamaterials

'Giant' charge density disturbances discovered in nanomaterials: Juelich researchers amplify Friedel oscillations in thin metallic films November 26th, 2014

Lawrence Livermore researchers develop efficient method to produce nanoporous metals November 25th, 2014

Research yields material made of single-atom layers that snap together like Legos November 25th, 2014

Aromatic food chemistry to the making of copper nanowires November 24th, 2014

Announcements

SEMATECH to Showcase Innovation and Advances in Manufacturing at SEMICON Japan 2014: SEMATECH experts will share the latest techniques, emerging trends and best practices in advanced manufacturing strategies and methodologies November 26th, 2014

Australian startup creates world’s first 100% cotton hydrophobic T-Shirts November 26th, 2014

The mysterious 'action at a distance' between liquid containers November 26th, 2014

'Giant' charge density disturbances discovered in nanomaterials: Juelich researchers amplify Friedel oscillations in thin metallic films November 26th, 2014

Patents/IP/Tech Transfer/Licensing

Dicerna Announces License Agreement with Tekmira to Advance Dicerna’s PH1 Development Program November 17th, 2014

First genetic-based tool to detect circulating cancer cells in blood: NanoFlares light up individual cells if breast cancer biomarker is present November 17th, 2014

Ki-Bum Lee Patents Technology To Advance Stem Cell Therapeutics November 13th, 2014

'Direct writing' of diamond patterns from graphite a potential technological leap November 5th, 2014

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







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE