Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > When atoms are getting close: Shortest carbon-chlorine single bond detected until now

Abstract:
The description of compounds and interactions between atoms is one of the basic objectives of chemistry. Admittedly, chemical bonding models, which describe these properties very well, already exist. However, any deviation from the normal factors may lead to improving the models further. Chemists with Professor Thomas M. Klapötke at Ludwig-Maximilians-Universität (LMU) München have now analyzed a molecule, which has an extremely short bond length. As reported by the researchers in Nature Chemistry, the carbon atom and the chlorine atom in the so-called chlorotrinitromethane molecule are only 1.69 Angstroms apart from one another. "Non-covalent interactions are one of the factors responsible for this short distance", declared Göbel, whose doctoral thesis revealed the new results. "A better understanding of these interactions is important and useful in all areas, where molecular recognition and self-assembly come into play." (Nature Chemistry, 3 May 2009).

When atoms are getting close: Shortest carbon-chlorine single bond detected until now

Germany | Posted on May 4th, 2009

Chemical bond models that have been successfully used for well over a century assume that a good description of the properties of a compound can be obtained while ignoring all but the nearest-neighbour bonding interactions. The idea that electrostatic interactions between second, third and even further neighbors are important and should not be ignored has not been a common notion so far. The team of Professor Thomas M. Klapötke of the Department of Chemistry and Biochemistry at LMU Munich, primarily concerned with the synthesis and investigation of new high-energy materials, has now demonstrated for the first time that even second and third neighbors can have a decisive effect on the properties of a chemical bond.

For their investigation, the researchers chose the so-called chlorotrinitromethane molecule, a compound, consisting of the halogen chlorine and the pseudohalogen trinitromethyl group. The latter is composed of one carbon atom and three nitro groups. The trinitromethyl unit belongs to the group of pseudohalogens, which has properties similar to those of the halogens. Both groups are composed of non-metals, which are generally present in the gaseous or liquid state and form salts with metals. Contrary to the halogens, however, the pseudohalogens, instead of being true chemical elements, are chemical groups composed of different elements.

Using X-ray structural analysis, the researchers succeeded for the first time in revealing the internal structure of the chlorotrinitromethane molecule and drawing conclusions concerning the distances between the individual atoms. In their analyses, the chemists came up against a particularly interesting property of the chlorotrinitromethane molecule, namely the distance between its chlorine atom and its carbon atom is only 1.69 Angstroms. An Angstrom is 10-7 millimeters. The distance, now detected between the atoms, is the shortest distance ever observed for comparable chlorine-carbon single bonds. All previously measured distances fall within the range of approximately 1.71 and 1.91 Angstroms.

By means of theoretical calculations, carried out in cooperation with Professor Peter Politzer and Dr. Jane S. Murray of the University of New Orleans in the USA, the researchers were able to reproduce the distribution of electrical charges within the molecule. It turned out that the chlorine atom has a completely positive electrostatic potential, a rare case, since chlorine usually has a negative electrostatic potential in other molecules. Together with the charge distributions of the remaining atoms, this finding explains why the chlorine and carbon atoms are linked so tightly to one another. The results impressively show that electrostatic interactions between atoms within a molecule can have a significant effect on bond lengths, even if these atoms are not linked directly to one of the two atoms that form the bond.

In the case of chlorotrinitromethane, this effect is particularly pronounced and leads to an unusually short chlorine-carbon bond. However, it could be of importance in various other cases, especially in areas, where molecules recognize one another and assemble to larger structures. These mechanisms play an important role, for example, in biological systems and in nanotechnology.

Publication: "Chlorotrinitromethane and its exceptionally short carbon-chlorine bond";
Michael Göbel, Boris H. Tchitchanov, Jane S. Murray, Peter Politzer and Thomas M. Klapötke;
Nature Chemistry online,3 May 2009
DOI: 10.1038/nchem.179

####

For more information, please click here

Contacts:
Luise Dirscherl

49-892-180-2706

Any correspondence should be addressed to:
Professor Thomas M. Klapötke
Department Chemistry and Biochemistry
Division Inorganic Molecule Chemistry
Phone.: +49-(0)89 / 2180 77504
Fax: +49-(0)89 / 2180 77492

Website: www.chemie.uni-muenchen.de/ac/klapoetke/

Copyright © Ludwig-Maximilians-Universität München

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

Tissue regeneration using anti-inflammatory nanomolecules August 22nd, 2014

A breakthrough in imaging gold nanoparticles to atomic resolution by electron microscopy August 22nd, 2014

Ultra-short pulse lasers & Positioning August 21st, 2014

Malvern’s Dr Alan Rawle talks TLAs in plenary lecture at Particulate Systems Analysis conference August 21st, 2014

Chemistry

Production of Toxic Ion Nanosorbents with High Sorption Capacity in Iran August 17th, 2014

Scientists fold RNA origami from a single strand: RNA origami is a new method for organizing molecules on the nanoscale. Using just a single strand of RNA, this technique can produce many complicated shapes. August 14th, 2014

Could hemp nanosheets topple graphene for making the ideal supercapacitor? August 12th, 2014

Iranians Find Novel Method for Processing Highly Pure Ceramic Nanoparticles August 12th, 2014

Discoveries

Tissue regeneration using anti-inflammatory nanomolecules August 22nd, 2014

A breakthrough in imaging gold nanoparticles to atomic resolution by electron microscopy August 22nd, 2014

Shaping the Future of Nanocrystals: Berkeley Lab Researchers Obtain First Direct Observation of Facet Formation in Nanocubes August 21st, 2014

Water window imaging opportunity: A new theoretical study elucidates mechanisms that could help in producing coherent radiations, ultimately promoting high-contrast imaging of biological samples August 21st, 2014

Announcements

Tissue regeneration using anti-inflammatory nanomolecules August 22nd, 2014

A breakthrough in imaging gold nanoparticles to atomic resolution by electron microscopy August 22nd, 2014

Malvern’s Dr Alan Rawle talks TLAs in plenary lecture at Particulate Systems Analysis conference August 21st, 2014

Water window imaging opportunity: A new theoretical study elucidates mechanisms that could help in producing coherent radiations, ultimately promoting high-contrast imaging of biological samples August 21st, 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