Pages

September 29, 2010

44 carbon atoms of polyyne carbon made, polyyne can be 40 times harder than diamond

Ad Support : Nano Technology   Netbook    Technology News    Computer Software

Polyyne is believed to be 40 times harder than diamond.

Eric Drexler discusses the synthesis of the longest polyyne chain to date, a chain of 44 carbon atoms.

Peierls instability is the reason that polyyne is so strong and the reason that it is tough to make.

A Peierls transition or Peierls distortion is a distortion of the periodic lattice of a one-dimensional crystal. Atomic positions oscillate so that the perfect order of the 1-D crystal is broken.



Nature Chemistry - Synthesis of polyynes to model the sp-carbon allotrope carbyne

Carbyne is an allotrope of carbon composed of sp-hybridized carbon atoms. Although its formation in the laboratory is suggested, no well-defined sample is described. Interest in carbyne and its potential properties remains intense because of, at least in part, technological breakthroughs offered by other carbon allotropes, such as fullerenes, carbon nanotubes and graphene. Here, we describe the synthesis of a series of conjugated polyynes as models for carbyne. The longest of the series consists of 44 contiguous acetylenic carbons, and it maintains a framework clearly composed of alternating single and triple bonds. Spectroscopic analyses for these polyynes reveal a distinct trend towards a finite gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital for carbyne, which is estimated to be ~485 nm (~2.56 eV). Even the longest members of this series of polyynes are not particularly sensitive to light, moisture or oxygen, and they can be handled and characterized under normal laboratory conditions.


68 pages of supplemental information

If you liked this article, please give it a quick review on Reddit, or StumbleUpon. Thanks

Supporting Advertising

Business Success
   How to Make Money    
Executive Jobs   
Paid Surveys


Thank You
blog comments powered by Disqus