Home > Press > An Odd Couple
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),
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
Amy Molnar (US)
Jennifer Beal (UK)
Alina Boey (Asia)
Copyright © Wiley InterScience
If you have a comment, please Contact
Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.
News and information
Canatu Launches CNB In-Mold Film for Transparent Touch on 3D Surfaces –in Cars, Household Appliances, Wearables, Portables November 20th, 2014
Sustainable Nanotechnologies Project November 20th, 2014
Quantum mechanical calculations reveal the hidden states of enzyme active sites November 20th, 2014
UO-industry collaboration points to improved nanomaterials: University of Oregon microscope puts spotlight on the surface structure of quantum dots for designing new solar devices November 20th, 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
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
Sustainable Nanotechnologies Project November 20th, 2014
Total Nanofiber Solutions Company FibeRio® Launches The Fiber Engine® FX Series Systems with 10X Increase in Output November 18th, 2014
Nanocomposites Strengthen Bone Implants November 13th, 2014
Production of Magnetic Nanoparticles with New Structures in Iran November 13th, 2014
Purdue 3-D printing innovation capable of making stronger, lighter metal works for auto, aerospace industries November 20th, 2014
Leica Microsystems Presents Universal Hybrid Detector for Single Molecule Detection and Imaging at SfN and ASCB: Leica HyD SMD - the Optimal Detector for Precise and Reliable SMD data November 20th, 2014
Silver Nanoparticles Produced in Iran from Forest Plants Extract November 20th, 2014
Nano Sorbents Able to Remove Pollutions Caused by Oil Derivatives November 20th, 2014
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