Sir Harold Kroto (1998) - C60-Buckminsterfullerene: Not just a Pretty Molecule

Well, I’ll just shout then, OK? I am going to talk about this molecule, and other aspects of it. Bob Curl has given you a very nice introduction of the discovery at Rice - and as most people know I can’t stand a jacket for very long, so I take that off - and try to explain why it has got a lot of other things going for it. Maybe it’s not much use but it still seems to do something that some people like. The question is why, and I like to show this picture of Brunovsky playing with his grandchild. And I don’t know how many of you had this toy when you were kids, small. Can you put your hands up? Come on, come on! How many people didn’t have it? There are an awful lot of disadvantaged people here in Germany. Anyway, it turns out that one child, every time they picked the cube up, they tried to put it through the round hole, and then they picked the triangular one and put that through the round hole, and whatever it was it was always the round hole, nothing else would matter. And the mother took the child to see a psychiatrist at this point, and the psychiatrist said, “What is it? It doesn’t matter what it is, it is always the same solution, is that right?” His mother said, “Yes.” “Well, there is only one career for this kid, and that is to be a politician, Frau Kohl.” OK. Now then, I think the aspect that is interesting is symmetry. And if we look at these objects we find that they are plutonic structures that were found in Scotland, and they were found something like not that long ago, but they are about three thousand years old. And they were found at the site of the first Glasgow Rangers vs. Celtic football match. In those days British supporters used to carve the stones into nice shapes before they threw them at the opposition! And if we look at the work of Piero della Francesca we see this beautiful drawing of a truncated icosahedron, and if we look at the work of Leonardo da Vinci we see also that he was fascinated by symmetry, and in fact we see something else, and that is that, in fact, that he was left-handed, he wrote from right to left, so with modern technology we can change it round. Now also the Greeks were very interesting, and they also had a chemistry. In the Timaeus, which is the only decent chemistry book that I have ever seen, one finds a very interesting statement and I hope you can read that. bounded by surfaces and all rectilinear surfaces are composed of triangles.” I hope that is clear to everyone here, because on the basis of that Plato developed the chemistry, and that there were only five elements in this and these are the Platonic structures. Now, it turned out that when I became a spectroscopist, I discovered a very similar statement in the work of van Vleck, which was that practically everyone knows that the components of total angular momentum of the molecule relative to X, Y, Z fixed in space satisfy this commutation relationship. Now, we came to Lindau on Saturday, and walked around Lindau island and we found that there was not a single person on Lindau island that actually knew this. It is quite clear that the previous Nobel Prize winners who have been coming every year have been dilatory and should really go out on the streets and teach them this, because on the basis of these equations we get the periodic table. We get, in fact, when j is zero 2j+1 is one, and if j is one it becomes three and five and so we get the structure of the periodic table. The whole of chemistry is explained by that. And as van Vleck said I ought to know, I thought I’d better do that, and I was told to read the theory of atomic spectra and in that, of course, one comes to the most important page which is this one, which I decided I’d better know this, because this is the interaction of radiation with matter. And symmetries are involved in this. And one reason for having this start is that there is beauty not just in the symmetry of objects but in the symmetry and beauty of the mathematical relationships of angular momentum. And you only have to look at this, which is Dirac’s treatment of the interaction of a photon with a molecule to how realize it’s got to be right because it’s so beautiful it must be right and it’s so beautiful and so powerful you’d better learn it because that’s essentially how you see. Now the question is about fundamental science and before I go into a little bit about C60 it’s important to realize that there are problems with fundamental science and one of them in Britain is the following: that one of the people on the EPSRC Users’ Panel says, “I’m uncomfortable with the idea of blue skies research because it implies an activity with little sense of direction.” Now I was in San Francisco last year and there was a beaten up Volvo, and on the bumper there was this wonderful statement from Tolkien which was: “Not all those who wander are lost.” I believe that is fundamental science. OK? There are many young scientists here today and I think you have a problem, because I don’t think I have too many idols, but I think Feynman probably is one of them, and I take something that was written up just recently about him. And it is here that Schrieffer, who later won the Nobel Prize for his theory of superconductivity, is telling how, in 1956, he heard Feynman give a talk in which he explained in loving detail everything that was wrong with his, Feynman’s, own failed theory of superconductivity, clearly signposting all the false trails so that other researchers could avoid them. Schrieffer had never heard such honesty from a colleague. Now can you image getting a grant and it goes wrong, and writing up that it went wrong and then hoping to get another grant? Well, that’s the problem that we actually face. Well, there are many aspects of science and in fact I’ve got another 3 hours’ lecture in this parliament so the only way I can solve this is to talk 4 times as quickly as I normally talk, which people tell me is too fast. But it’s important to realize that when I first started this, and in fact Professor Mäder is here from Kiel, he will know that really I was a microwave spectroscopist and I used to look in the grass, I hope you can see this, this is my favourite molecule. You might think it’s C60, but my favourite molecule is actually this guy, which is the first carbon phosphorous double bonded species. And I disobeyed Wilson’s rule, I assigned this on the basis of a single line, which Bob knows is something you’re not supposed to do, but if you do that you’d better be right. And I point out that we assigned C60 on the basis of a single line and of course we had to be right on that as well. And during that period of working on phosphorous compounds and other molecules, David Walton actually got me hooked and in fact chained by these carbon chains, to these long carbon chain molecules which I’ll show you here. in space and I ended up with Bob and Rick and Sean O’Brien and Jim Heath and I thought I’d show you these two guys because, this is them, because these are the guys who actually did essentially all the work. I could sit there in front of the machine and these things would just come up and just sit there and Jim and Sean would jump around the apparatus. I’ll put it the right way round so you can see, because we were hard at work drinking Budweiser and Coors and eating chicken fajitas, but also Yuan Liu, who’s back in the States, was also involved in this, so I thought I’d show you this because as you know three guys got the Nobel Prize and the students they got a very good meal, I mean…..But don’t worry, you get to be supervisors , too, and your students get very good meals, too, and hopefully you get the big prize. But, in fact, we found ourselves very fortunate that we were working with such a fantastic group of kids and also that this football came over our backyard, really, and I think in many ways it’s a really fascinating story. Well, I won’t bore you with it again, because I heard you already, as I said in this morning’s presentation, that there were two copies of something that a politician or someone had mentioned it. But I will tell you some people complain about the name buckminsterfullerene and, in fact, we had a bit of a discussion, but Bob and Rick basically gave in, because they sort of realized that there was going to be bad news if they didn’t, because it would have an even worse name, which is the correct name of C60 to deal with. This tells you something about IUPAC, because this is the IUPAC name for C60. Now it turns out that when I got back to Sussex, we didn’t have any lasers so we actually tried the carbon arc experiment and it’s an interesting one, and we also had a bell jar and I want to show this picture of Jonathan Hare and, it’s a long story, but we started and then a beautiful paper by Krätschmer and Huffman came out and it was sent to me, and we got back on this because for various reasons we couldn’t get any support for this, and this paper came out and, it’s important to realize that Krätschmer and Huffman did a fantastic piece of real science. I can’t do justice to it, but I knew Wolfgang and we got back onto this project, and one day Jonathan Hare put a red solution on my desk. In fact, he left it over the weekend, put this on my desk, and on the Thursday, on the Friday, I got a call from Nature, that’s the journal, and they wanted to ask me whether I would referee this paper and this fax came at 12.05 –‘Solid C60 - a new form of carbon’. And I read this paper through, and I read this through here, now, I hope you can read it, it says it produces a wine-red brown liquid, and I’m looking at something that looks not a lot different to a wine-red brown liquid and thinking “This is not so good!” I mean, I know Germany beats us in the World Cup every bloody time, but this is serious! And anyway, I thought what should I do? Should I commit suicide or go for lunch? Now, it turns out, many of you have been to England, eating lunch in England is roughly the same as committing suicide, as you well know! So, hey man, ‘Würstchen’ isn’t that good either, I tell you, you know! Anyway, as I read the paper through, I think this is one of the great papers of the 20th century, because in that paper there were these crystals of pure carbon. If anybody had said to anybody 1985 to 1990 that you could take pure carbon and crystallize it and use these as Krätschmer and Huffman and their students Kostas Fostiropoulos and Lowell Lamb did, then they would just not believe you and they would put you away. Now it turned out that it was absolutely correct and it gave a beautiful crystal structure and as I looked through this paper I realized there was one thing missing, and that there was no NMR in that paper. And my colleague Roger Taylor said he would help us, and he discovered that you could chromatographically separate these into two solutions, a red one which was C70 and a magenta one, and in fact we sent it down to NMR and C60 has in fact got 60 equivalent carbon atoms, and so I thought, well, if we can get the NMR, at least we can salvage a little bit, and we’d ride on the coattails of Krätschmer and Huffman’s beautiful paper with the NMR. And we were looking for a single line, that was wonderful because I like single lines. And in fact, Tony Evans sent us this, right. Now you may think this is a beautiful single line but when we went in Tony said, And he said, “But if you really look hard, see this thing, I reckon that’s C60.” And in fact that was correct. And that’s the first NMR detection of C60, and in fact, we went on to get C70 which is 5 lines. And so, I’d like to show you a picture, you’ve seen one picture, and in fact I’ll show you another picture, this is without the missing woman, she’s left now, we didn’t put her on the paper so she decided she didn’t want to be on the picture, but in fact the group at Sussex is Dave Walton, Roger and Abdul Sattar and Jonathan Hare, who actually really believed he had C60 and put this on my desk. Before going, we should really pay, I think, real respect to many people, but I think also as well, I hope you can read all this now, but in fact here on page 178 is C60. There were others that Bob mentioned and that it’s really very, very, very nice that it was thought of by Japanese scientists. Well, what can you do with it? Before I go I’m going to show you that you can do chemistry with this fella. One way of doing chemistry, if you’re like me, is to get someone who can do chemistry, to do it, or, you can do something else. You can just take a model and stick the groups on, OK?, which I’ll now do. If you take one pentagon and go one spoke out from each of these pentagons, you can add groups on to it, like this. And if we do that, this is the easy way of doing it - Paul Birkett who made this compound is a superb scientist and he has shown that you can actually make the compound itself - and then put this on here and put that on there. You can put 5 feet onto C60, and you’ve got to have an even number so we can put a hydrogen on here, and now you get a sort of animal that can walk around on 5 legs, bit fossilized, the hydrogen on here balances it up and as you notice we’ve only made the male of the species so far, OK? You can pass that round, OK? Now, what else can you do? You can make these nanotubes, which Bob talked about, and they’re very interesting because they’re half of C60 on one end and half on the other end. They’re a tube of pure graphite and they’re a single molecule. This single molecule could be maybe one day metres long. And, as Bob pointed out, if you can make them in bulk - and that’s something for you smart guys - we’ve done the easy thing, right, you’ve gotta do the hard guy stuff and put them together and make the material that will revolutionise civil engineering and electronics in the future. When I first made it I called it a Zeppelin, for obvious reasons, but the students decided they ought to call it Viagrine now! OK. Well, we’ve only got another two hours left. OK, so let me talk a little bit about what we’ve been doing. We’ve been trying to understand these nanotubes, and I can only talk a little bit about them. They’re fascinating things and the way that they were discovered was again a truly imaginative piece of science by a Japanese Sumio Iijima. And taking the carbon arc here, whilst the rest of us were making C60 as madly as possible, Iijima was probably the world’s greatest electron microscopist and he looked at the tip of the cathode and he discovered that there was in fact a small sort of crust on the cathode, which formed as you kept it going, you get a formation on the cathode, and it had a hard shell, and I hope you can see 7 millimetre diameter. And if you scrape this out and what you get are nanotubes. And, in fact, as it happened, I was the referee of this paper, as well. And here is this first picture of these absolutely sensational sort of structures. And, in fact, what you’re looking at is an electron microscope image, and if you take one of these objects you get a phase relationship only in the edge. As the electron beam goes through here there is a relationship and an interference on the edge which doesn’t occur across the tube. And so electron microscopy is a very nice way of studying this, in fact the carbon nanotubes are probably the best things to study in one of these systems. And there are many things you can do. For instance, you can have helical structures, and in fact they’re very strong because in some carbon fibres, when you crack them, you find that a strong nanotube comes out of the centre. These are from Professor Endo in Nagano. Here is a carbon fibre which has been cracked, and as you pull it apart, a nanotube comes out because they don’t break, they bend, and don’t break. And we’ve been trying to understand these. The other thing that’s quite nice is that they’re called Buckie tubes. That’s quite nice because Buckminster Fuller had patents on these as well. Now I can’t go through these in detail, but we’ve got a really good bunch of students and we made some of these and Mauricio Terrones made this material, which roughly looks like spaghetti. And we wanted to make them straight, so one thing I wanted to do was to take a sort of substrate and grow these things straight out of this, like asparagus. And so we irradiated a silica plate with cobalt on it and made lines on that and we grew from these little clusters, these are cobalt and nickel clusters on a surface, and hoped that they would grow nice and straight. Well, that’s not so straight as you quite clearly see. And now Mauritio, he said, “Well, why don’t we grow them upside down, because, then, you know, gravity will pull them down?” Like any good supervisor, you say, “Well, that’s rubbish,” right? But, like any good student, he doesn’t take any notice, right. As long as he doesn’t blow himself up, it doesn’t matter very much. So, now, anything I say they do the opposite, so what happens is, they did straighten out. So here’s the next lesson: probably 9 out if 10 times, your supervisor is gonna be right, but the tenth time he’s gonna be wrong, and that’s gonna be the real time when it will really be good. And, in fact, it turns out they are quite straight, and very, very interesting. I really can’t do much justice to this, except that we think we’ve got some understanding of how the metal tube actually makes nanotubes. What I think is happening is that amorphous carbon is forming a carbide, say a molybdenum carbide or a tantalum carbide or aluminium carbide, and then this is ordered, so the amorphous material now forms a crystalline carbide, which then segregates as ordered carbon, which forms a tube. It’s the craziest possibility, but it does look as though that’s what might be happening in this particular case. And we’ve got an example of this, which is shown here. You see amorphous material in this and then it forms a sort of carbide-type material which then comes off here and forms a tube. You can see that there’s a three-walled nanotube here, this is a carbide-type material and here is the amorphous-like material. So it’s like meat grinder, you take this meat and you put it through the meat grinder and it orders it. When it segregates it’s now ordered and it can form graphite, graphitic material. We’ve got quite a few examples, this is the best one to show that this type of process can, and does seem to, occur. The other thing I’d like to mention, we’ve got lots of great students, and I don’t know why this was done. When Kuang Hsu looked at electrolysis between carbon electrodes, and here is a carbon crucible, with an electrode dipping into it, and he found some nanotubes in this experiment. And to give you an idea, here are these tubes which are forming in condensed medium. So it looks as though you can actually make these nanotubes by electrolysis and that looks very exciting for the next round of nanoscale engineering. Well, there’s a lot I could talk about, but I’d like to finish off with a few other things that we at Sussex have been involved with, with C60. I don’t know how many books there are left in here, it’s like Christmas, there are another two left. You’ve only got another….. Don’t worry. I’m going to talk about C60 and its relationship to many things, such as science and the media. Here’s one of the problems that we as scientists face and can scientists shake off their mad media image? And it turns out that I know who’s responsible for this problem, and the point is that if only Einstein had cut his hair, I think we wouldn’t have the problem. And, in fact, I cut my hair before coming here for this particular meeting. This is the man who actually invented those beautiful theories, and it presents some sort of problem, because when science gets into the literature and gets into the newspapers, here is an example, a typical one. I know you’re all destined, you want to be scientists, but this is the way the newspapers look at you. I am a carbon copy and there’s a caricature here. I put it up on the noticeboard and one of the students wrote “Fantastic likeness, Harry” here. I made him write an extra thesis for his PhD for writing that. But in Spain it’s much better, because in fact, in Cadiz, when they had me on the front page, here, I was dancing with Naomi Campbell at the time, the flamenco. And the Spanish newspapers didn’t take her photograph, they just took mine, which was very nice. The other thing is, when we discovered the long chains as life’s key might lie among the stars, a student wrote “That’s showbiz” here. I made him write two extra theses for writing that one. But, in fact, when you read that article through, it said the chemicals were discovered thanks to Canadian work in radioastrology and research by the Sussex team. Now, I believe this problem now has to be solved, and the problem is that it’s a language problem. Let me give you an example of language. There are several of these but here is one. The study of fast reactions, the German scientist Manfred Eigen asked Ronnie Bell how the English language would describe reactions which were faster than fast. Ronnie Bell replied “’Damn fast reactions, Manfred!’ And if they get faster than that, English will not fail you, you can call them ‘Damn fast reactions indeed!’” Let me give you an example of science as a language. My friend, Maynard Smith, John Maynard Smith, had to write an article and he was told by the editor of the journal, or the magazine, not to put any equations in it. But he had to put one, and he put this one in, and the editor rang him up and said, “John, you’ve put an equation in. Is it really necessary?” He said, “Yes, it’s really necessary, I have to put that equation in.” And he said, “Well, can’t you please simplify it by cross-multiplying the ‘d’s?” Well, that’s the problem. So how to solve it? Well, before I go on, I’d like to tell you something about, that’s the language in journalism. What about politicians? In the House of Lords, there was a question by Lord Erroll of Hale, who asked Her Majesty’s government what steps they were taking to encourage the use of buckminsterfullerene in science and industry? This was the reply. It actually makes more sense this way than the right way up. Lord Williams of Elvel said, “My Lords, is the noble Lord aware in supplementing his answer, that the football-shaped carbon molecule is also known for some extraordinary reason as Buckie ball?” Well that was something, but Baroness Seear then went on to say, I can say that buckminsterfullerene is a molecule composed of 60 carbon atoms, known to chemists as C60, those atoms form a closed cage made of 12 pentagons and 20 hexagons that fit together like the surface of a football.” And then my favourite question. sound up on the roof, and they looked up and there was the one person who knew the answer. It turns out that your DNA is only about 0.01 per cent difference from this guy; it’s about 10% difference from the guys in the House of Lords, though, so don’t worry. Well, what can we do to solve this problem? And there are so many young students here today. Well, let me tell you that it’s something to do with education. And C60 and the work that you do, you have to find ways of making it exciting and realizing that the things that excite you about science can excite young kids. Not just in Germany but in Japan. And also here are some Hispanic kids whose first language is Spanish, in Santa Barbara, and we do not only just show these things, we actually do some real mathematics using Euler’s Law and taking the number of faces plus the number of corners minus the number of edges is equal to two. Now, as Bob told you, Rick and I and none of us knew this, but it’s a fantastic formula, because we can take a cube, OK, with six faces, and eight corners, and subtract the twelve edges with kids, and show them with the use of formula it comes out with two, they learn something about symmetry, OK. And that’s how we do a fair amount of science with them. Not only that they go around and they make these little molecules, they can actually do lots of things, like they can experiment with these, make hats out of C60. I want to now finish with the last thing that we’ve been involved with, and that is, we’ve now set up a trust to make science films for television and I hope you’ll all take this website down, and in fact there are some leaflets down here in the right-hand corner. I’m going to put them down. We’ve made 30 programmes and they’re real scientists’ programmes. In fact, we’ve made the first programme, which actually shows what a fantastic communicator Sir John Cornforth is. He has been here, but he’s been deaf since the age of twenty, that’s one of the most important programmes that we’ve ever made. We’ve made programmes by David Miller, “There ain’t nothing nowhere” talking about the structure of the vacuum. We’ve made programmes on the origin of life, Bill Klemperer on chemistry and interstellar space. Science and fine art. Jocelyn Bell who discovered the pulsar - that programme is there as well. We’re now within sight of a science night on UK television and hopefully on European television. And I think the scientific community has got to get together now to actually solve this problem. The best one so far that we’ve made is this one on the structure of DNA, and I don’t know that I can show this, but I’ll have a go, because each of these programmes has some real science in it. Hopefully we can do this display. Let me see whether I can show it. Now then, on this slide I have a set of horizontal lines. Can anybody see anything on that with a set of spots? Probably at the back you can’t, but you can come up later and see this. Anyway by going through this, if you have a set of horizontal lines you get a set of vertical dots, I just don’t have a powerful enough laser to show it here. But, anyway, when you go through this, you get to a zig-zag, and when you look at the zig-zag you get a cross. Can anyone…. Who can see a cross? OK, wonderful eyesight you Germans have got. Now I can’t see where you are. Right, I’ve got a set of horizontal lines, OK. Can you see that? Now then this is a set of lines at an angle and any other angle, now a zig-zag, and the crucial thing is that zig-zag is a cross. Now then, when you go to a helix, it’s also a cross, but when you get to the double helix - can any of you see a missing spot? That is exactly Rosalind Franklin’s X-ray pattern of DNA. This is going to be the way that perhaps the greatest discovery of the 20th century was actually made. And you can just do a Fourier transform with a hand-held laser and a slide like this. And one of our programmes with Amand Lucas actually shows that. We’ve got those programmes, each one is a scientific programme and on television in the future we’ve got to have real science. I’m going to finish off, I think, with my last slide, if I can find it, because I think it’s nearly now finished. Yes, here we go. The first thing is that, I’d like to show the last but one slide, because it pertains to this fantastic couple of lectures that we had before. And I’m sure Mario Molina’s lecture will be equally stimulating, equally problematical, and maybe most of your students should actually try and help and solve this problem. But I’ve got this that I want to show you, because it’s the way that I feel. I was sent from another planet with a message of goodwill from my people. The message says: ‘Dear Earth people. When you finally at last destroy your planet and have no place to live, you can live with us and we will teach you how to live in peace and harmony. And we will give you a coupon fit for 10% off all deep-dish pizzas, too.’” He’s my sort of guy. And I’m sure he’s Sherry Rowland’s and Mario Molina’s and Paul Crutzen’s sort of guy as well. Yes, OK; C60 hasn’t done much, but I tell you, anything that can get a kid to look like this has got to be good. Thank you very much.

Sir Harold Kroto (1998)

C60-Buckminsterfullerene: Not just a Pretty Molecule

Sir Harold Kroto (1998)

C60-Buckminsterfullerene: Not just a Pretty Molecule

Comment

Amongst the Nobel Laureates lecturing in Lindau, Sir Harold Kroto would probably earn the award for the most unusual and characteristic way of presenting. This lecture, which is the first he ever gave in Lindau, is no exception. Kroto`s way of presenting relies on a quick succession of, sometimes loosely connected, images, which are, in a most creative fashion, gathered from the spheres of history, arts, science, society etc. This brings about a relaxed and - at the same time - enriched and intense atmosphere, which is usually highly appreciated by the Lindau audiences.Unfortunately, there is no video available for this particular lecture and thus a great deal of the unique “Harry Kroto spirit” is lost. Still, the lecture is special, because it is not only the first Lindau lecture Kroto gave after receiving the Nobel Prize, but also the last he gave so far (2012) on the subject of his Nobel Prize research. In later years, Kroto gave preference to more general subjects such as creativity or science, society and sustainability. Kroto and his co-recipients Robert F. Curl Jr. and Richard F. Smalley shared the 1996 Nobel Prize in Chemistry "for their discovery of fullerenes". Fullerenes are ball-shaped molecules built exclusively from carbon. The most famous fullerene, the Buckminster fullerene (sometimes also referred to as C60), contains 60 carbon atoms and looks pretty much like a football. The fullerenes were so exciting to the scientific community (and the Nobel Committee) because they represented a new modification of carbon, which is distinctly different to the well-known graphite and diamond modifications. Due to the fundamental importance of carbon in almost all processes of life as well as in materials science, it could be expected that the advent of the fullerenes would entail a horn of plenty of potential technical applications. This excitement was stimulated further, when traces of fullerenes were detected in space.However, as far as we know today, the enthusiasm was probably excessive. More than 25 years after the discovery of fullerenes, there are still no major technical applications, or, as Robert Curl put it in his 1998 Lindau talk: the discoverers are still waiting for their kid to get a job. Today, new carbon modifications, such as carbon nanotubes and graphene (Nobel Prize in Physics 2010), which might well be considered advancements of fullerene research, have taken over the role of hope bearers in the field of carbon-only materials. In the present talk, Kroto uses his characteristic presentation style to blend historical snippets with details on his own scientific background, anecdotes on fullerene research as well as some brief notes on the fullerenes’ chemical properties. The breadth of his point of view might be estimated from two of the quotes he uses. The first one, given in a rather ironic context, is attributed to the Greek philosopher Plato, 360 BC:“In the first place it is clear to everyone that fire, earth, water and air are bodies and all bodies are solids and all solids again are bounded by surfaces and all rectiliniar surfaces are composed of triangles.”The second one comes straight from a Lord of the Rings bumper sticker and is used by Kroto to make an argument in favour of fundamental science:“Not all those who wander are lost.”The author of this comment could not agree more.David Siegel

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