Nucleation, growth and size-distributions of Ge islands on Si(001): in-situ STM studies

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Welcome to the High Pressure Mineral Physics and
Materials Sciences Laboratory
 
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Diamond Anvil Cell -Window to the Earths Interior
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Structure of the Earth Interior
The three concentric layers - the core, mantle,
and crust formed within a few hundred million
years of Earth's coalescence 4.5 billion years
ago.
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The Temperature of the Earths Interior
Temperature in oC
1000
2000
4000
6000
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Pressure Distribution inside the Earth
Depth
Pressure (bar)
670 km
2.3x105
1.3x106
2900 km
1.3x106
5154 km
6400 km
3.6x106
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The major minerals inside the Earth
olivine
spinel
perovskite
post- perovskite
molten iron
Fe-Ni
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History

•  The first river-bed (alluvial) diamonds were
  probably discovered in India, in around 800 B.C.
• In South Africa in 1870 diamond was found in the
  earth far from a river source, and the practice
  of dry-digging for diamonds was born.

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The Kooh-i-noor
The Kooh-i-noor has a longest history for an
extant stone. Firstly, in 1304 as a diamond in
the possession of the Rajah of Malwa, later, it
fell into the hands of the Sultan Baber. This was
a time when possession of such a gem symbolized
the power of an empire.
(109 carats)
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The Koh-i-Noor was presented to Queen Victoria in
1850 to mark the 250th anniversary of the
founding of the East India Company. It was
displayed at the Crystal Palace Exposition
In 1911 a new crown was made for the coronation
of Queen Mary with the Koh-i-Noor as the center
stone. In 1937, it was transferred to the crown
of Queen Elizabeth (now Queen Mother) for her
coronation. It is now on display with the British
Crown Jewels in the Tower of London.
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Orloff Diamond 189 carats
First, it may have been set at one time as the
diamond eye of Vishnu's idol (one of the Hindu
Gods) in the innermost sanctuary temple in
Sriangam, before being stolen in the 1700s by a
French deserter.
The time passed, the stone arrived at Amsterdam
where the Russian count Grigori Orloff was
residing. The stone has been called the Orloff
since then. Catherine received his gift and had
it mounted in the Imperial Sceptre. In 1812 the
Russians, fearing that Napoleon with his Grand
Army was about to enter Moscow, hid the Orloff in
a priest's tomb. Napoleon supposedly discovered
the Orloff's location and went to claim it.
However, as a solider of the Army was about to
touch the Orloff, a priest's ghost appeared and
pronounced a terrible curse upon the Army. The
Emperor, Napoleon scampered away without the
Orloff.
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The Tiffany (128 carats), the best known yellow
diamond.
Cullinan, 530 carats
Pumkin Diamond
The Hope, Hope was once owned by Louis XIV and
was officially designated "the blue diamond of
the crown."
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Diamond Mining
An "independent" operation using the simplest
technology shovel, pan, water, and muscles.
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Structures of Graphite and Diamond
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Eiffel Tower, Paris

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Diamonds can form at depths as shallow as 150
kilometers beneath the continental crust, while
beneath oceans they need depths of at least 200
kilometers, as shown by the diamond boundary on
the cross-section. Graphite is transformed in
diamond under high pressure 55000 atmospheres and
1400 degrees Co.
This magnitude of pressure is difficult to
comprehend. For example, the pressure of 55,000
atmospheres necessary to make a diamond at 1400
degrees C (orange hot) would require the Eiffel
Tower (7000 metric tons) resting on a 5 inch
plate.

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Large Volume Press at SOEST
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Structure of the new C3N4 phase synthesized at
SOEST
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Structure of Fullerene
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Structure of Nanotubes
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The Future
The space shuttle presently uses diamond-coated
low-friction hinges in various moving parts, but
future uses may include diamond windows and
diamond radiation-detectors in scientific
instruments, and electronics with diamond
heat-spreaders or flat panel displays with
diamond-powered pixels.
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Mahalo