by Antony Williams PhD, Vice President of Strategic Development, Royal Society of Chemistry
When doodling in a planning meeting last year Professor Graham Richards of Oxford University, considered a molecular structure with three hexagonal rings above two other rings that would make for an interesting synthetic challenge. With the support of an international collaboration of scientists the doodle was brought to reality in a little over a year. Based on its shape the doodle became known as “olympicene”, a compound with interesting electronic and optical properties, that could potentially be used for the next generation of solar cells and high-tech lighting sources such as LEDs.
Richards’ doodle eventually made it into the hands of chemists at the University of Warwick. After several months olympicene was finally produced by Anish Mistry, from the David Fox group, using a multi-step synthesis. The compound is a powder, that is very sensitive to light. In fact, even with brief exposure it changes color. A complete profile and many of the reaction steps for olympicene can be found in the online database ChemSpider SyntheticPages.
Samples of the isolated materials generated during the multi-stage synthesis were analyzed at Warwick using standard spectroscopic techniques such as nuclear magnetic resonance and mass spectrometry, which measures the mass of particles. The team also performed analyses using microscopy, but were not satisfied with the resolution.
Coincidentally, I had recently become interested in the work of a small team at IBM in Switzerland that had developed a complex technique to image or “take a picture” of molecules in the journal Nature — it turned out to be the coup de grace for the team.
Back in 2009, at the IBM Research lab in Zurich scientists imaged, for the first time, the chemical structure of an individual molecule with unprecedented resolution, using technique they developed called noncontact atomic force microscopy. In a press release on the achievement IBM scientists loosely compared the technique to “how a doctor uses an X-ray to image bones and organs inside the human body.”
Fast forward to 2012. After scientists at Warwick pushed the limits of imaging the olympicene with their microscopy equipment they contacted the IBM scientists in an attempt to see whether they could use their technique for even greater resolution. The result? A beautifully rendered image of a single molecule of olympicene.
IBM scientist Leo Gross and his colleagues from the IBM Research Lab collaborated with Ben Moreton, from the Giovanni Costantini group at the University of Warwick, to generate the spectacular images shown here.
One particular challenge for Dr. Gross and the team was that they had to abstract a single hydrogen atom from olympicene. This is not something that can be done with a pair of tweezers — when you consider that olympicene is only 1.2 nanometers wide, or 100,000 times thinner than a human hair, it is an impressive feat.
The next step will be to publish the findings in a scientific journal and to look for applications of the compound.
It took a team of scientists interested in collaboration, the joy of science and a passion for pushing the boundaries to get here. Truly a celebration of international collaboration and innovative science at its best.