From Football
to Nanotechnology
Common
Form of Carbon Molecules
Chemists had
known for a long time that pure carbon normally
came in two common molecules forms: graphite and
diamond. Carbon normally has 6 protons and 6 neutrons.
A small amount of carbon has 8 instead of 6 neutrons,
and we call them carbon-14, an important carbon
isotopes used for dating historical materials. Carbon
can extend four bonds, making it very versatile
chemically to become a fundamental element of life
on Earth.
Graphite
Graphite is the most common form of carbon. It composes
of flat sheets of hexagons like an honeycomb beehive.
It is a black substance which is used in paints,
electrical apparatus and for the writing material
in the middles of pencils. Coal and petrol are improved
forms of carbon.
Diamond
Diamond is a very hard form of carbon. As its abundance
is rare, it is very valuable. It appears in native
usually as colourless precious stone, and is useful
for cutting things and in jewellery. Each atom in
diamond is bonded to four others in a tetrahedral
arrangement which gives the structure considerable
intrinsic strength and hardness.
Proposals
on a new form of carbon molecule
In 1966, David Jones,
using the pesudoruym Daedalus, written in New Scientist
of a proposed new form of carbon that would be made
of 60 carbon atoms in a cage form. Around the period
some other scientists had made similar proposals.
But this form of carbon was taken as pure entertainment
and considered impractical as candidates for synthesis
in laboratory.
A
self-constructed stable form of giant carbon molecules
In 1985, Robert F. Cure,
Harold W. Kroto, and Richard E. Smalley together
discovered a new form of element carbon that was
made of 60 carbon atoms. They further discovered
that this was just one of the forms that create
a carbon cage. The new forms are later collectively
called fullerenes.
Nomenclature
These new forms of carbon
was named after Buckminster Fuller, a pioneer in
the research and construction of geodesic dome structures.
One of Fuller masterpiece is the Geodesic Dome for
the 1967 Montreal World Exhibition. They were first
named Buckminister fullerenes, but later settled
into a shorter name fullerenes.
An institute named after
Buckminster Fuller
http://www.bfi.org/
Nobel
Prize in Chemistry
Cure, Kroto and Smalley
shared together the 1996 Nobel Prize in Chemistry
because of their discovery of fullerenes. The Nobel
Prize press release links:
http://www.nobel.se/chemistry/laureates/1996/press.html
Commemorative
Stamp
The Royal Mail of UK
had issued a set of stamps to celebrate 100 years
of Nobel Prizes. The carbon-60 molecule was chosen
as a representative of the Nobel Prizes in Chemistry.
http://www.royalmail.com/stamps/2001_collection/2001Collection/factfile.asp?
strSection=2001Collection&strHead=2001Collection&strSubHead=factfile&strPageFile=
../monthly_files/1.htm&strTemplate=factfile&factmonth=10
Family
members of fullerenes
Information of the Family
members of fullerenes is available in these websites.
1. The pioneer of discovering the Carbon -60 molecule
is at
http://cnst.rice.edu/smalleygroup/res.htm
2. A fairly detailed
website on bucky ball is at:
http://buckminster.physics.sunysb.edu/
This is the home page
of current research carried by Laszlo Mihaly's laboratory
at the Physics Department in SUNY @ Stony Brook.
3. The Fullerene Family
is at:
http://membres.lycos.fr/thomaslaude/intro.htm
Nanotechnology
Nanotechnology is the
science on a scale of nanometres (billionths of
a metre), the size realm of individual molecules.
As nanotechnology is a fast growing branch of science,
this web page only covers the role of carbon-60
molecule in nanotechnology.
Buckyballs
and AIDS
In 1993, scientists worked
out a synthesis for di-phenethylaminosuccinate fulleroid,
leading to an astounding story: buckyballs(i.e.
fullerenes) inhabit the AIDS virus. They tried to
block the active site in a key enzyme in the human
immunodeficiency virus known as HIV-1 protease using
fullerene. It provides a good starting point to
develop suitable drugs based on fullerene chemistry.
Some researchers had compared this to the discovery
of benzene, another carbon molecule, from which
40 percent of today's drugs, such as aspirin, are
made.
Buckyballs Make Fantastic Voyage
http://www.wired.com/news/medtech/0,1286,45481,00.html
Inside
stories
Atoms capable of being
encapsulated in a C60 / fullerene cage were being
studied. This was then extended to include small
molecules such as carbon monoxide. Metal-encapsulating
fullerenes are also under well researches.
Nanotubes
and nanoworms
Derived from the fullerenes,
nanotubes are structures formed from the vapourization
of graphite rods containing gadolinium or gadolinium
oxide, and consist of central cores of either amorphous
gadolinium carbide or single crystal GdC2 with carbon
nanotubes radiating outwards like a sea urchin.
In the same sense, nanoworms are structures consisting
of a "head" made from a cubit palladium
crystal inside a hyperfullerene and a segmented
"tail" of carbon tubes.
Nanotube site:
http://www.pa.msu.edu/cmp/csc/nanotube.html
A carbon nanotube site:
http://www.rdg.ac.uk/~scsharip/tubes.htm
Nanoworm site:
http://op.virtualave.net/cgi-bin/boardpower/discussion.cgi?forum=3&discussion=16
http://www.ul.ie/~childsp/CinA/issue50/carbon.html
http://www.iscpubs.com/pubs/glevy/levy598.html
Mesozoic
fullerenes
About 65 million years
ago, the extinction of the dinosaurs was triggered
by a global cataclysmic event thought to be associated
with the impact of a large meteor. The impact is
thought to have caused massive wildfires which poured
smoke and soot into the atmosphere, blocking the
light from the Sun. This event marked the end of
the Mesozoic era. In geological terms, it is identified
by a thin layer of soot at the Cretaceous/Tertiary
(K/T) boundaries. This layer was found to contain
some fullerenes.
Studies of geological samples
from the K/T boundary revealed the presence of
C60 . No C60 have been detected in samples of
Cretaceous limestone just below, Tertiary shale
just above the boundary layer.
Extinctions Tied to Impact
from Space
http://www.sciencenews.org/20010224/fob1.asp
Fullerenes
in space
In 1994, scientists studied
a tiny crater formed by the impact of a carbonaceous
micrometeoroid on an aluminum panel of a spacecraft
to find signatures of C60 and C70 . Continuous research
has been carried out to investigate if C60 is indeed
a "celestial sphere".
http://www.mpi-stuttgart.mpg.de/andersen/fullerene/cosmos.html
Buckyballs from Outer Space
http://www.spacescience.com/headlines/y2000/ast21mar_1.htm
Nanomaterials :
www.asm-intl.org/
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