2011 Nobel Prize in Chemistry goes to quasicrystals

Well, I think it’s fair to say that this year’s Chemistry Prize caught everyone off guard. The award to Daniel Shechtman for the discovery of quasicrystals was absent from all the prediction lists. On Twitter, the overwhelming response to the news was: “What are quasicrystals?”

For a good, thorough overview of quasicrystals, see this article (HT Ian Sample at the excellent Guardian liveblog). In simple terms, quasicrystals have regular elements, like normal crystals do, but these elements fit together in ways that never fully repeat themselves.

This might sound rather un-Nobel-worthy, but in fact, the story behind Shechtman’s discovery fulfills many the classic themes found within memorable Prize-awarded achievements — a scientist who goes against conventional thought, pursues the evidence rather than the story, and despite peer ridicule is eventually proved to be correct.

In Shechtman’s case his discovery of quasicrystals fundamentally changed the way chemists look at solid matter.  Here’s a nice video in which Shechtman discusses his discovery and its implications:

The official background information for the prize also paints a lovely picture of the morning of 8 April 1982, when Shechtman saw an image in his electron microscope that breached the laws of nature.

“Eyn chaya kazoo”, Daniel Shechtman said to himself. “There can be no such creature” in Hebrew… The material he was studying, a mix of aluminum and manganese, was strange-looking, and he had turned to the electron microscope in order to observe it at the atomic level. However, the picture that the microscope produced was counter to all logic: he saw concentric circles, each made of ten bright dots at the same distance from each other.

To say that Shechtman’s peers dismissed the finding as an experimental artifact would be a huge understatement. On his “In the Pipeline” blog, Derek Lowe provides a nice bit of personal perspective on the response:

I was in grad school when the result came out, and I well remember the stir it caused. Just publishing the result took a lot of nerve, since every single crystallographer in the world would tell you that if they knew one thing about their field, it was that you couldn’t have something like this.

For a full account of the reaction, I recommend you read this article from 2001 by Shechtman’s colleague John Cahn and this blogpost by Greg Laden. This quote from the prize background material gives a flavour of what occurred. Remember, this came from people in Shechtman’s own workplace.

[Shechtman] was faced with complete opposition, and some colleagues even resorted to ridicule. Many claimed that what he had observed was in fact a twin crystal. The head of the laboratory gave him a textbook of crystallography and suggested he should read it. Shechtman, of course, already knew what it said but trusted his experiments more than the textbook. All the commotion finally led his boss to ask him to leave the research group.

As this Associated News article reveals, the scientific community reacted with uproar when Shechtman’s findings were published in 1984, most notably by two-time Nobel Laureate Linus Pauling. According to Shechtman, Pauling said: “Danny Shechtman is talking nonsense. There is no such thing as quasicrystals, only quasi-scientists.” (You can read Pauling’s letter to Nature disputing Shechtman’s results here.)

When asked today by Adam Smith from Nobelprize.org what his experience of discovering quasicrystals taught him about science, Shechtman responded: “It taught me that a good scientist is a humble scientist who is open-minded to listen to other scientists when they discover something.” It’s a lesson for us all.

For journalists, Shechtman’s tale of triumph against scientific ridicule and adversity isn’t the only compelling story linked with this prize. There’s also the issue of who else could, or should, have been included. Almost immediately, people asked why the name of mathematician Roger Penrose was absent. The atoms in Shechtman’s quasicrystals are arranged like patterns called Penrose tiles, which the mathematician devised in the mid-1970s. When asked why Penrose wasn’t included, the Chemistry Prize committee said they were acknowledging the discovery specifically, a definition that also appears to rule out the physicist Paul Steinhardt, who actually coined the term “quasicrystals”.

UPDATE: Ian Sample has in fact just posted some quotes from Penrose on Twitter, including his opinion as to whether Shechtman’s ideas for quasicrystals had been influenced by Penrose tiling (pasted below).

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