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Literary Freeware: Not For Commercial Use
From THE MAGAZINE OF FANTASY AND SCIENCE FICTION, July 1992
F&SF Box 56 Cornwall CT 06753 $26/yr; outside USA $31/yr
F&SF Column #2
BUCKYMANIA
Carbon, like every other element on this planet, came to us from
outer space. Carbon and its compounds are well-known in galactic
gas-clouds, and in the atmosphere and core of stars, which burn
helium to produce carbon. Carbon is the sixth element in the periodic
table, and forms about two-tenths of one percent of Earth's crust.
Earth's biosphere (most everything that grows, moves, breathes,
photosynthesizes, or reads F&SF) is constructed mostly of
waterlogged carbon, with a little nitrogen, phosphorus and such for
leavening.
There are over a million known and catalogued compounds of
carbon: the study of these compounds, and their profuse and intricate
behavior, forms the major field of science known as organic
chemistry.
Since prehistory, "pure" carbon has been known to humankind
in three basic flavors. First, there's smut (lampblack or "amorphous
carbon"). Then there's graphite: soft, grayish-black, shiny stuff --
(pencil "lead" and lubricant). And third is that surpassing anomaly,
"diamond," which comes in extremely hard translucent crystals.
Smut is carbon atoms that are poorly linked. Graphite is carbon
atoms neatly linked in flat sheets. Diamond is carbon linked in strong,
regular, three-dimensional lattices: tetrahedra, that form ultrasolid
little carbon pyramids.
Today, however, humanity rejoices in possession of a fourth
and historically unprecedented form of carbon. Researchers have
created an entire class of these simon-pure carbon molecules, now
collectively known as the "fullerenes." They were named in August
1985, in Houston, Texas, in honor of the American engineer, inventor,
and delphically visionary philosopher, R. Buckminster Fuller.
"Buckminsterfullerene," or C60, is the best-known fullerene.
It's very round, the roundest molecule known to science. Sporting
what is technically known as "truncated icosahedral structure," C60 is
the most symmetric molecule possible in three-dimensional Euclidean
space. Each and every molecule of "Buckminsterfullerene" is a
hollow, geodesic sphere of sixty carbon atoms, all identically linked in
a spherical framework of twelve pentagons and twenty hexagons.
This molecule looks exactly like a common soccerball, and was
therefore nicknamed a "buckyball" by delighted chemists.
A free buckyball rotates merrily through space at one hundred
million revolutions per second. It's just over one nanometer across.
Buckminsterfullerene by the gross forms a solid crystal, is stable at
room temperature, and is an attractive mustard-yellow color. A heap
of crystallized buckyballs stack very much like pool balls, and are as
soft as graphite. It's thought that buckyballs will make good
lubricants -- something like molecular ball bearings.
When compressed, crystallized buckyballs squash and flatten
readily, down to about seventy percent of their volume. They then
refused to move any further and become extremely hard. Just *how*
hard is not yet established, but according to chemical theory,
compressed buckyballs may be considerably harder than diamond.
They may make good shock absorbers, or good armor.
But this is only the beginning of carbon's multifarious oddities in
the playful buckyball field. Because buckyballs are hollow, their
carbon framework can be wrapped around other, entirely different
atoms, forming neat molecular cages. This has already been
successfully done with certain metals, creating the intriguing new
class of "metallofullerites." Then there are buckyballs with a carbon or
two knocked out of the framework, and replaced with metal atoms.
This "doping" process yields a galaxy of so-called "dopeyballs." Some
of these dopeyballs show great promise as superconductors. Other
altered buckyballs seem to be organic ferromagnets.
A thin film of buckyballs can double the frequency of laser light
passing through it. Twisted or deformed buckyballs might act as
optical switches for future fiber-optic networks. Buckyballs with
dangling branches of nickel, palladium, or platinum may serve as new
industrial catalysts.
The electrical properties of buckyballs and their associated
compounds are very unusual, and therefore very promising. Pure C60
is an insulator. Add three potassium atoms, and it becomes a low-
temperature superconductor. Add three more potassium atoms, and it
becomes an insulator again! There's already excited talk in industry of
making electrical batteries out of buckyballs.
Then there are the "buckybabies:" C28, C32, C44, and C52. The
lumpy, angular buckybabies have received very little study to date,
and heaven only knows what they're capable of, especially when
doped, bleached, twisted, frozen or magnetized. And then there are
the *big* buckyballs: C240, C540, C960. Molecular models of these
monster buckyballs look like giant chickenwire beachballs.
There doesn't seem to be any limit to the upper size of a
buckyball. If wrapped around one another for internal support,
buckyballs can (at least theoretically) accrete like pearls. A truly
titanic buckyball might be big enough to see with the naked eye.
Conceivably, it might even be big enough to kick around on a playing
field, if you didn't mind kicking an anomalous entity with unknown
physical properties.
Carbon-fiber is a high-tech construction material which has
been seeing a lot of use lately in tennis rackets, bicycles, and high-
performance aircraft. It's already the strongest fiber known. This
makes the discovery of "buckytubes" even more striking. A buckytube
is carbon-fiber with a difference: it's a buckyball extruded into a long
continuous cylinder comprised of one single superstrong molecule.
C70, a buckyball cousin shaped like a rugby ball, seems to be
useful in producing high-tech films of artificial diamond. Then there
are "fuzzyballs" with sixty strands of hydrogen hair, "bunnyballs"
with twin ears of butylpyridine, flourinated "teflonballs" that may be
the slipperiest molecules ever produced.
This sudden wealth of new high-tech slang indicates the
potential riches of this new and multidisciplinary field of study, where
physics, electronics, chemistry and materials-science are all
overlapping, right now, in an exhilirating microsoccerball
scrimmage.
Today there are more than fifty different teams of scientists
investigating buckyballs and their relations, including industrial
heavy-hitters from AT&T, IBM and Exxon. SCIENCE magazine
voted buckminsterfullerene "Molecule of the Year" in 1991. Buckyball
papers have also appeared in NATURE, NEW SCIENTIST,
SCIENTIFIC AMERICAN, even FORTUNE and BUSINESS WEEK.
Buckyball breakthroughs are coming well-nigh every week, while the
fax machines sizzle in labs around the world. Buckyballs are strange,
elegant, beautiful, very intellectually sexy, and will soon be
commercially hot.
In chemical terms, the discovery of buckminsterfullerene -- a
carbon sphere -- may well rank with the discovery of the benzene ring
-- a carbon ring -- in the 19th century. The benzene ring (C6H6)
brought the huge field of aromatic chemistry into being, and with it a
enormous number of industrial applications.
But what was this "discovery," and how did it come about?
In a sense, like carbon itself, buckyballs also came to us from
outer space. Donald Huffman and Wolfgang Kratschmer were
astrophysicists studying interstellar soot. Huffman worked for the
University of Arizona in Tucson, Kratschmer for the Max Planck
Institute in Heidelberg. In 1982, these two gentlemen were
superheating graphite rods in a low-pressure helium atmosphere,
trying to replicate possible soot-making conditions in the atmosphere
of red-giant stars. Their experiment was run in a modest bell-jar
zapping apparatus about the size and shape of a washing-machine.
Among a great deal of black gunk, they actually manufactured
miniscule traces of buckminsterfullerene, which behaved oddly in their
spectrometer. At the time, however, they didn't realize what they
had.
In 1985, buckministerfullerene surfaced again, this time in a
high-tech laser-vaporization cluster-beam apparatus. Robert Curl
and Richard Smalley, two professors of chemistry at Rice University
in Houston, knew that a round carbon molecule was theoretically
possible. They even knew that it was likely to be yellow in color. And
in August 1985, they made a few nanograms of it, detected it with
mass spectrometers, and had the honor of naming it, along with their
colleagues Harry Kroto, Jim Heath and Sean O'Brien.
In 1985, however, there wasn't enough buckminsterfullerene
around to do much more than theorize about. It was "discovered,"
and named, and argued about in scientific journals, and was an
intriguing intellectual curiosity. But this exotic substance remained
little more than a lab freak.
And there the situation languished. But in 1988, Huffman and
Kratschmer, the astrophysicists, suddenly caught on: this "C60" from
the chemists in Houston, was probably the very same stuff they'd
made by a different process, back in 1982. Harry Kroto, who had
moved to the University of Sussex in the meantime, replicated their
results in his own machine in England, and was soon producing
enough buckminsterfullerene to actually weigh on a scale, and
measure, and purify!
The Huffman/Kratschmer process made buckminsterfullerene
by whole milligrams. Wow! Now the entire arsenal of modern
chemistry could be brought to bear: X-ray diffraction,
crystallography, nuclear magnetic resonance, chromatography. And
results came swiftly, and were published. Not only were buckyballs
real, they were weird and wonderful.
In 1990, the Rice team discovered a yet simpler method to make
buckyballs, the so-called "fullerene factory." In a thin helium
atmosphere inside a metal tank, a graphite rod is placed near a
graphite disk. Enough simple, brute electrical power is blasted
through the graphite to generate an electrical arc between the disk
and the tip of the rod. When the end of the rod boils off, you just crank
the stub a little closer and turn up the juice. The resultant exotic soot,
which collects on the metal walls of the chamber, is up to 45 percent
buckyballs.
In 1990, the buckyball field flung open its stadium doors for
anybody with a few gas-valves and enough credit for a big electric
bill. These buckyball "factories" sprang up all over the world in 1990
and '91. The "discovery" of buckminsterfullerene was not the big kick-
off in this particular endeavour. What really counted was the budget,
the simplicity of manufacturing. It wasn't the intellectual
breakthrough that made buckyballs a sport -- it was the cheap ticket in
through the gates. With cheap and easy buckyballs available, the
research scene exploded.
Sometimes Science, like other overglamorized forms of human
endeavor, marches on its stomach.
As I write this, pure buckyballs are sold commercially for about
$2000 a gram, but the market price is in free-fall. Chemists suggest
that buckmisterfullerene will be as cheap as aluminum some day soon
-- a few bucks a pound. Buckyballs will be a bulk commodity, like
oatmeal. You may even *eat* them some day -- they're not
poisonous, and they seem to offer a handy way to package certain
drugs.
Buckminsterfullerene may have been "born" in an interstellar
star-lab, but it'll become a part of everyday life, your life and my life,
like nylon, or latex, or polyester. It may become more famous, and
will almost certainly have far more social impact, than Buckminster
Fuller's own geodesic domes, those glamorously high-tech structures
of the 60s that were the prophetic vision for their molecule-size
counterparts.
This whole exciting buckyball scrimmage will almost certainly
bring us amazing products yet undreamt-of, everything from grease
to superhard steels. And, inevitably, it will bring a concomitant set of
new problems -- buckyball junk, perhaps, or bizarre new forms of
pollution, or sinister military applications. This is the way of the
world.
But maybe the most remarkable thing about this peculiar and
elaborate process of scientific development is that buckyballs never
were really "exotic" in the first place. Now that sustained attention
has been brought to bear on the phenomenon, it appears that
buckyballs are naturally present -- in tiny amounts, that is -- in almost
any sooty, smoky flame. Buckyballs fly when you light a candle, they
flew when Bogie lit a cigarette in "Casablanca," they flew when
Neanderthals roasted mammoth fat over the cave fire. Soot we knew
about, diamonds we prized -- but all this time, carbon, good ol'
Element Six, has had a shocking clandestine existence. The "secret"
was always there, right in the air, all around all of us.
But when you come right down to it, it doesn't really matter
how we found out about buckyballs. Accidents are not only fun, but
crucial to the so-called march of science, a march that often moves
fastest when it's stumbling down some strange gully that no one knew
existed. Scientists are human beings, and human beings are flexible:
not a hard, rigidly locked crystal like diamond, but a resilient network.
It's a legitimate and vital part of science to recognize the truth -- not
merely when looking for it with brows furrowed and teeth clenched,
but when tripping over it headlong.
Thanks to science, we did find out the truth. And now it's all
different. Because now we know!
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