Archive for the ‘atomic force microscopy’ tag
Seeing molecules
I have a great deal of respect for the early pioneers of chemistry — not just because they were intelligent and inquisitive and spawned entire fields of research, but mainly because they were able to do this while never having the ability to see what they were studying. So, although the early experimenters could conduct experiments to indirectly validate or invalidate their hypotheses on a macro-scale (like shaking a tree to see what fruit fell out rather than actually looking up at the tree to see the individual fruit), the fact that they could never see or manipulate or count molecules meant that most of their work resided in the domain of thought experiments.
And, although the scientific community now take the existence of atoms and molecules for granted, I think the early Avogadros of chemistry would have been especially gratified by the recent work at IBM’s research facility in Zurich to use atomic force microscopy to actually see molecules of pentacene (five fused aromatic 6-carbon rings, pictured below)
The results are detailed both on IBM’s press page as well as in the Aug 28 issue of Science. But, in graphical terms, this is the scientific community’s current best picture of pentacene:
Amazing isn’t it? More of the technical details are presented in the video IBM put together in conjunction with the press release (below), but in a nutshell, atomic force microscopy uses a well-defined atomic tip to “feel” out the electronic surface of a molecule. The ability to do this and even be able to resolve the respective hydrogen atoms is a testament to IBM’s ability to put together an incredibly stable (both to mechanical and thermal fluctuations) and precise setup.
From IBM’s perspective, this breakthrough allows them to continue to push ahead on the advanced nanotechnology and semiconductor research which they depend on to churn out next-generation electronics, but for the scientific community, these advances could result not only in better atomic force microscopy experimental techniques, but potentially also a new way to understand and study the chemical reactions and structures which have such great influence over our lives.
Publication: Science 28 August 2009: Vol. 325. no. 5944, pp. 1110 – 1114; DOI: 10.1126/science.1176210
(Image credit – Pentacene chemical diagram) (Image credit – AFM picture)
