Regular and symmetrical geometric figures are always fascinating and thought-provoking. The ancient Greeks used the tetrahedron, cube, octahedron, dodecahedron, and icosahedron to represent the elements fire, earth, air, and water that make up the universe, and ether, which makes up the celestial bodies, respectively. They are collectively known as Platonic solids. Kepler also had an idea and proposed a universe model composed of the inner and outer tangents of five Platonic polyhedrons. He believed that the ratio of the radii of these inner and outer tangent spheres was the ratio of the orbits of the six known planets at that time, and praised him as the god of the universe. Heavenly masterpiece.
So when scientists announced in September 1985 that they had discovered an ultrastable C60 molecule shaped like a "truncated icosahedron," it caused quite a stir. The discoveries of those 11 days were full of surprises and surprises, and it was a joy to talk about.
The story originated from Croto (Sir) of the University of Sussex in the United Kingdom. His research focuses on microwave spectroscopy, which is used to analyze the atmospheric composition of space planets and interstellar gas clouds. At the time he was interested in giant stars with high carbon content, and when analyzing their atmospheric lines, he found that they could be attributed to cyanopolyynes, long chain molecules made of carbon and nitrogen, the same molecules also Exist in interstellar gas clouds. Croto believes that these carbon compounds come from planetary atmospheres rather than interstellar gas clouds, so he hopes to further study the formation mechanism of such long-chain molecules.
On Easter 1984, Croto visited F. Curl, Jr. at Rice University in the United States. Curl suggested visiting a group developed by his colleague and research partner (E.). The laser-supersonic beam instrument (Figure 1) vaporizes matter into an atomic gas, forming clusters of tens of atoms held together. Croto believes that the instrument can be used to simulate the chemical environment in a planet's atmosphere and provide evidence for the formation of long-chain carbon compounds in high-temperature regions of a planet's atmosphere. He explained the idea to Cole, who suggested that they collaborate on research together.
Figure 1 Laser-ultrasound beam instrument. A pulsed laser is focused on a graphite disc, and carbon atoms are ejected, mixed into a jet of supersonic high-density helium gas injected through a small hole, forming carbon clusters into a collection cup, and then allowing them to expand outward (modified)
After about a year and a half of preparation, Croto arrived in Houston on September 1, 1985, and immediately joined Cole, Smalley, students Heath, O'Brien, Liu Yuan, and others (Figure 2). As a result of the experimental work, it was found in just 10 days that when solid graphite was used as the target (Fig. 1), molecules synthesized from various even numbers of carbon atoms could indeed be produced. Surprisingly, C60, consisting of 60 atoms, is the most abundant, almost all C60 in some specific cases, and is extremely stable and extremely low in activity. After repeated scrutiny and discussions, the research team finally concluded on September 10, speculating that its structure should be a "truncated icosahedron", a hollow cage like a sphere, with 60 vertices and 32 faces, of which Twelve are regular pentagons and 20 sides are regular hexagons (Figure 3). They decided to name it Fullerene, in homage to Fuller (R.), the architect of the US Pavilion who designed the geodesic vault for the Montreal World's Fair in 1967.
The research team finished writing the paper on September 11 and submitted it to the journal Nature the next day. "was published on November 14, less than 2 pages, and the title is "C60:" (Buckminster • Fullerene), so it is also referred to as "Bucky Ball" ().
Since the structure of the "truncated icosahedron" is extremely symmetrical and ingenious, after the experimental results spread, it aroused great attention from everyone. In 1990, physicists Hoffman (R.) and Kräsmer (Krä) announced that two graphite rods were placed in helium, and a voltage was applied to generate an arc, which vaporized the graphite and recondensed the carbon gas When dissolved in an organic solution, crystals of C60 can be obtained, confirming the speculation of C60. In 1996, Croto, Smalley, and Cole shared the Nobel Prize in Chemistry.
Figure 2 "", 1985 Paper C60: Group photo of the authors, from left: O', , Cole, and (provided)
The Kroto family is a Polish-Jewish family, originally named Krotosna (), who later immigrated to Germany, and their parents fled to England during the Nazi period. Croto was born in Cambridgeshire in 1939, received his doctorate from the University of Sheffield (of Eld) in 1964, and was hired by the University of Sussex three years later. In addition to science, Crotone was also obsessed with the art of painting on a professional level. In 1995, under the auspices of the Royal Society, he established the Vega Science Trust (Vega) to produce science documentaries to advance science. In 2005, he left the University of Sussex to take up a Chair Professorship at Florida State University.
Born in Akron, Ohio, USA in 1943, Ph.D. He graduated from Princeton University in 1973 and began his teaching and research career at Rice University in 1976. His research focuses on studying the formation mechanisms of non-organic and semiconductor clusters using molecular beams and time-of-flight mass spectrometry. After the discovery of fullerenes, he began research on the iron-catalyzed synthesis of carbon nanotubes, leading to the creation of the US National Nanotechnology Initiative in 2000. In 2005, he died of chronic lymphocytic leukemia.
Cole was born in Alice City, Texas, USA in 1933. He graduated from Rice University and went to the University of California, Berkeley for further study. After winning the Nobel Prize, he continued teaching and research. He said: "After winning, he may become the godfather of science, or come up with new ideas for scientific directions, and use his fame to get the resources he needs; but he may also say: 'Well, I want to continue your work. A job I love."
Figure 3 "truncated icosahedron" model
After Hoffman and Kramer found a synthetic method that could be mass-produced, the research on fullerenes made rapid progress. For example, they discovered carbon nanotubes with a structure similar to fullerenes, which have good thermal and electrical conductivity and amazing tensile strength. As the third carbon substance after diamond and graphite, the research of fullerene has become a field of chemistry, and its application value depends on the further research and efforts of scientists.
The discovery story of Fullerenes shows that when scientists with different expertise collaborate, unexpected and incredible sparks can erupt; successful transnational collaborations have also become a new trend in scientific research.
(This article is reproduced from "Physics Bimonthly" in October 2014, website:tw)