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Jumat, 07 Oktober 2011

Israeli Chemist Wins Nobel Prize For Quasicrystals

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Nobel laureate Daniel Shechtman.

Israeli scientist Daniel Shechtman won the 2011 Nobel Prize in chemistry on Wednesday for his discovery of quasicrystals.

The 1982 breakthrough fundamentally changed the way chemists look at solid matter, the Royal Swedish Academy of Sciences said.

Scientists used to believe that atoms were arranged inside crystals only in ordered, repeating patterns. Shechtman's work showed that the atoms could be packed in a pattern that did not repeat — a new chemical structure known as a quasicrystal.

NPR's Joe Palca said Shechtman was in the U.S. studying a mixture of aluminum and manganese through an electron microscope when he made the discovery. The microscope allowed him to see how the atoms in the compound were packed together — but the pattern didn't make sense because it seemed to violate the rules of nature by not repeating.

"This was such a fundamental change in what people understood about crystals that it just seemed impossible," Palca said. "So he sent in a paper to a scientific journal, and they basically sent it right back without even ... looking at it at all. But he knew he had something very weird."

All crystals were thought to have rotational symmetry, so that when they are rotated, they look the same. On April 8, 1982, Shechtman first observed crystals with 10 points — pentagonal symmetry, which most scientists said was impossible.

"I told everyone who was ready to listen that I had material with pentagonal symmetry. People just laughed at me," Shechtman said in a description of his work released by his university.

It took years for Shechtman and other researchers to prove that he was right, and he was asked to leave his research group in the course of defending his findings.

Even double Nobel winner Linus Pauling was among those who never accepted the research.

"He would stand on those platforms and declare, 'Danny Shechtman is talking nonsense. There is no such thing as quasicrystals, only quasi-scientists,' " said Shechtman, a professor of materials science at the Technion-Israel Institute of Technology in Haifa.

The type of nonrepeating patterns that follow mathematical rules seen in quasicrystals are also seen in tile mosaics across the Arabic world, most notably in buildings such as the Alhambra Palace in Spain and the Darb-i Imam Shrine in Iran. Mosaics like these from as early the 13th century, made of just five unique tiles, "have helped scientists understand what quasicrystals look like at the atomic level," the academy said.

Quasicrystals have been synthesized in laboratories around the world since their discovery in 1982, but it wasn't until 2009 that the first naturally occurring quasicrystals were found.

They have also been found in some of the most durable kinds of steel in the world, and they are used in products such as razor blades and thin needles used in eye surgery. Scientists are also experimenting with using quasicrystals in surface coatings for frying pans, heat insulation in engines, and energy-saving LED lights.

Shechtman will receive the 10 million kroner ($1.5 million) prize in December.

Material from The Associated Press was used in this story.

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Israeli Wins Nobel Chemistry Prize For Quasicrystals

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Israeli chemist Daniel Schectman's discovery of how atoms fit together inside of crystals changed the way chemists look at solid matter.

Copyright © 2011 National Public Radio®. For personal, noncommercial use only. See Terms of Use. For other uses, prior permission required.

LYNN NEARY, host: The Nobel Prizes are being awarded all this week. Today, the chemistry prize goes to Daniel Schechtman for his work on something called quasicrystals. Schechtman discovered these crystals in 1982, and they fundamentally changed the way scientists looked at solid matter. Joining me to discuss this year's prize is NPR science correspondent, Joe Palca.

Good to have you with us, Joe.

JOE PALCA: Good to be here.

NEARY: So tell us about Schechtman and his discovery.

PALCA: Well, Schechtman is an Israeli. He was born in Tel Aviv in 1941. And he's now a professor at the Technion-Israeli Institute of Technology in Haifa. In 1982, he was working on a sabbatical here in the United States in what was then called the National Bureau of Standards, now the National Institute of Standards and Technology. And he was looking at a mix of aluminum and manganese through an electron microscope. And when he - he saw a pattern through the microscope. It was very strange. It was 10 concentric dots. Now, what does that mean?

Well, to him it meant that these atoms were packing together in this mixture in a way that no one had seen before. Ten dots suggested there was something going on that was very strange, a kind of a 10-fold symmetry. And so he couldn't believe it at first, because it violated the rules of - then the rules of what crystals were.

NEARY: So did he see this over a period of time, or did he see it suddenly, all...

PALCA: No, this is one of those amazing things, Lynn. He actually saw it on a particular day. And here's Professor Sven Lidin of the Swedish Academy of Sciences at the press conference this morning, describing the work.

SVEN LIDIN: We can date this discovery perfectly. Often, the Nobel Prize is awarded to something that has developed over a long time. For this particular discovery, we know it took place on April the 8th, 1982.

PALCA: And that's because they have his lab notebook with the date on it, and also his writing in the margin, saying: Tenth? - question mark, question mark. So he obviously knew he had seen something very weird.

NEARY: So when he told the world about this discovery, what was the reaction?

PALCA: They didn't believe it.

(SOUNDBITE OF LAUGHTER)

PALCA: They said you've made a mistake. You're seeing something wrong. He sent in a paper. It was rejected right away. And it took almost two years just to get the paper published, and then it was not universally accepted, but obviously, over time, it did come to be accepted.

NEARY: All right. So this changes the way crystals are understood. But are there any practical implications to this at all?

PALCA: Well, yes. These crystals have some interesting properties. First of all, they're harder than other materials, in many cases. And so they've actually been - they're used in things like razor blades and surgical steel. They're also poor conductors of heat. And so they can be used as insulators, and they're also - they have what's called thermo-electric properties, which means when you heat them up, they give off an electric current. And so they're used in LEDs, these light-emitting diodes that are used in many kinds of displays.

Now, the other interesting thing that I found about this is that they - these crystals were never seen in nature before two years ago, when the first one that was ever discovered in nature was discovered in a river in Eastern Russia. So these have all been laboratory-built things. And what's different about these crystals from others is that crystals used to be defined as something that was regular and repeating - regular and repeating. But these quasi-crystals are regular in the sense that they're made of the same kinds of shapes, but the shapes go together in a non-repeating way. So they go on, but each - as you keep going, the patterns are different, even though the bits that go together are all the same.

NEARY: Hmm. So remind us, Joe, before we finish this, remind us of just how much this prize is worth.

PALCA: Well, the prize is worth 10 million Swedish kronor, which is about $1.5 million - U.S. dollars. And there's one other interesting thing about this prize - or at least I thought it was interesting. The prize goes to just one person. The other prizes awarded this week were to teams or groups.

NEARY: Yeah.

PALCA: And I thought that was unusual. But actually, I looked it up, and it turns out that 62 of the chemistry Nobels have gone to just one person. So - or now, 63. So I guess it's something you can do in a solitary way. You don't have to have pals to win the Nobel in chemistry.

(SOUNDBITE OF LAUGHTER)

NEARY: OK. Thanks, Joe. NPR's Joe Palca. Thanks so much for being with us.

PALCA: You're welcome.

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