April 2, 1991 sec B p1
by David Stipp
For those who missed the raft of scientific papers published recently on odd spherical molecules called buckyballs, now comes buckyball, the movie.
It's a video simulation made with the help of a supercomputer, featuring an innocently rolling buckyball that suddenly gets squashed between two walls of hard stuff. There is a happy ending, though. After the pressure is eased, the flattened ball pops back into shape, notes Donald Brenner, a researcher at the Naval Research Laboratory in Washington, D.C., who helped produce the simulation.
Not "Rocky IV" perhaps, but to scientists it is gripping, action-packed entertainment. The buckyball is physical science's hottest new star - it's hitting the gee-whiz button among physicists and chemists more often than anything has since the superconductor breakthrough five years ago. That's partly because the buckies are such oddballs, chemically speaking - they are only the third pure form of carbon to be discovered, after graphite and diamonds. And their unique properties suggest a bounty of commercial uses, including new lubricants, drugs, fuels, batteries and high strength materials.
"I meet many scientists and have been absolutely stunned" by the number working on buckyballs, says Robert D. Johnson, an International Business Machines Corp. researcher studying the molecules. By last fall, "every visiting group [of scientists] was working on this or knew someone who was."
Buckyballs resemble symmetrical spheres of chicken wire when depicted using chemist's ball-and-stick models. Their more formal name is buckminsterfullerenes, suggested by their resemblance to the geodesic domes of architect Buckminster Fuller. Buckyballs are thought to be formed-at least fleetingly-when carbon-containing substances, such as candles, are burned and make soot. But they weren't identified until 1985, when Richard Smalley, a Rice University physical chemist, and colleagues used a laser-zapping technique to spawn and isolate tiny amounts of them. With some ideas from Harold Kroto of England's University of Sussex, Mr. Smalley figured out their structure late on night by taping together paper polygons in his kitchen after loosening his imagination with beer.
The buckyball bonanza really started last fall, however, when a team of German and U.S. scientists published an easy way to make the molecules in sizable quantities. Their technique requires little more equipment than an ordinary arc welder-a major reason why so many scientists are jumping into the buckyball game.
Commercial caution is in order: Buckyball applications remain highly speculative for the reason that all the data aren't in on their basic properties yet. Some possibilities suggested in the first flush of excitement already are looking a little dubious. University of Arizona chemist Donald Huffman, who co-discovered the easy way to make buckyballs, says he sent some to Edwards Air Force Base in California to try as rocket fuel. In early tests, "they couldn't get it to ignite," he says.
But buckyballs do oxidize and break down when heated. That casts doubt on one early hope: applying the molecules like tiny ball bearings to lubricate hot engine parts. Moreover, they may be too small to lessen the rub between typical surfaces. "It might be like trying to lubricate the moon rubbing against the Earth by putting ping-pong balls on the mountains," says Rice's Mr. Smalley.
Still, the tiny balls may be just the thing to lubricate gears in "micromotors," suggests John Weaver, a University of Minnesota physicist. Such microscopic motors might someday be used in gnat-sized robots designed to clean clogged arteries and perform other chores in small places.
Unlike other forms of pure carbon, buckyballs dissolve in various solvents, making them easy to chemically manipulate, says IBM's Mr. Johnson. Thus, it may be fairly easy to customize them for certain uses, including lubrication, by chemically combining other atoms or molecules with them. Researchers at the University of California in Berkeley already have reported forming a buckyball variant resembling a purse with a handle. And polymers made from long chains of chemically altered buckyballs stuck together might provide extra strength in aircraft wings and other places, says Mr. Smalley.
The best-known buckyball contains 60 carbon atoms; but larger ones, some with hundreds of atoms, also are thought to exist. The size variations may be handy for applications based on the idea of placing atoms or other molecules inside the buckyballs. For instance, radioactive atoms for killing cancer cells might be sheathed in buckyballs before injection to help protect the atoms while they work against tumors. And batteries' charged particles-their electrically active ingredients- might last longer by "shrink-wrapping" them in buckyballs, scientists say.
Recent studies suggest buckyballs themselves can be turned into highly charged particles by well-known methods that strip away one or more of their carbon atoms' electrons. That means the balls alone might spawn new kinds of batteries. Charged buckyballs also can be accelerated by electric fields-if hurled into carbon or other surfaces, they might even exert enough pressure to form a thin layer of diamond, speculate some researchers; on the other hand, there is some evidence the buckyballs may just bounce off the surface. A kind of Bucky Rogers idea also has been proposed-blasting charged buckyballs out the tail of a spacecraft to propel it at high speeds to distant planets.
Farfetched suggestions for applying buckyballs seem natural as their exotic properties emerge. Among other things, the balls appear to be semiconductors-like the silicon used in computer chips. And researchers recently found that the balls form exotic crystals resembling hovering rows of spinning tops. Excitement about such surprises is helping to dispel a cloud over physics and chemistry lingering from bitter controversy about "cold fusion," the potential energy breakthrough that hasn't panned out, says Mark Ross, a researcher at the Naval Research Laboratory. The new buckyball game, he adds, is making scientists "like little kids again."