H
H
Hydrogen Bonding
at: code.enthought.com/.../mayavi/auto/examples.html
The water trimer has a chiral cyclic equilibrium structure with each water monomer acting as
a single hydrogen bond donor and acceptor (75, 98)
Keutsch F N, Saykally R J PNAS 2001;98:10533-10540
©2001 by The National Academy of Sciences
Two distinct tunneling pathways rearrange the hydrogen bond pattern in the cyclic water
trimer
Keutsch F N, Saykally R J PNAS 2001;98:10533-10540
©2001 by The National Academy of Sciences
The water tetramer has a highly symmetric homodromic S4 equilibrium structure resulting in
oblate symmetric top spectra with no vibrational averaging required
Keutsch F N, Saykally R J PNAS 2001;98:10533-10540
©2001 by The National Academy of Sciences
The high symmetry of the tetramer requires highly concerted tunneling motions and limits the
number of degenerate minima that can be connected on the IPS via feasible tunneling
motions to two
Keutsch F N, Saykally R J PNAS 2001;98:10533-10540
©2001 by The National Academy of Sciences
The water hexamer has been determined to have a cage structure with the oxygens forming a
distorted octahedron
Keutsch F N, Saykally R J PNAS 2001;98:10533-10540
©2001 by The National Academy of Sciences
e at: witcombe.sbc.edu/water/chemistryproperties.html
e at: witcombe.sbc.edu/water/chemistryproperties.html
image at: sciencechicagoblog.com/.../question-about-water/
What has happened is that there
has been a charge in the dipole
moment
dμ/dt ≠ 0
The water trimer has a chiral cyclic equilibrium structure with each water monomer acting as
a single hydrogen bond donor and acceptor (75, 98)
Keutsch F N, Saykally R J PNAS 2001;98:10533-10540
©2001 by The National Academy of Sciences
Two distinct tunneling pathways rearrange the hydrogen bond pattern in the cyclic water
trimer
Keutsch F N, Saykally R J PNAS 2001;98:10533-10540
©2001 by The National Academy of Sciences
The water tetramer has a highly symmetric homodromic S4 equilibrium structure resulting in
oblate symmetric top spectra with no vibrational averaging required
Keutsch F N, Saykally R J PNAS 2001;98:10533-10540
©2001 by The National Academy of Sciences
The high symmetry of the tetramer requires highly
concerted tunneling motions and limits the number of
degenerate minima that can be connected on the IPS
via feasible tunneling motions to two
Keutsch F N, Saykally R J PNAS 2001;98:10533-10540
©2001 by The National Academy of Sciences
The water hexamer has been determined to have a cage structure with the oxygens forming a
distorted octahedron
Keutsch F N, Saykally R J PNAS 2001;98:10533-10540
©2001 by The National Academy of Sciences
yedda.com
image at: www.meta-synthesis.com/.../LAB_matrix.html
The Antarctic Ice Sheet
The Antarctic Ice Sheet is a thick, ancient
sheet of ice with a maximum depth of
nearly 3 miles (15,000 feet). It is the
iceberg 'factory' of the Southern Ocean.
This icesheet contains over 5 million cubic
miles (30 million cubic km) of ice. The
weight of the Antarctic ice is so great that in
many areas it actually pushes the land
below sea-level. Without its ice cover
Antarctica would eventually rise up another
1500 feet (450 m) above sea-level. The Ice
Sheet is very gradually moving, in this case
towards the sea in a radial pattern.
With 98% of its surface covered with various forms
of snow and ice, it's no wonder that the continent of
Antarctica attracts "cold weather" scientists from all
over the world. Basically, Antarctica is a snow and
ice "factory" with ice depths on the Polar Plateau
reaching 15,000 feet (the continent's average ice
thickness is 7,000 feet). Thus, one of Antarctica's
most important resources is its ice. It is said that
Antarctica's ice accounts for 70% of the world's
fresh water. Some people have considered towing
icebergs from Antarctica to parts of the world in
need of fresh water.
As strange as it sounds, however, Antarctica is
essentially a desert. The average yearly total
precipitation is about two inches. So, where did all
this snow and ice come from? The answer lies in
Antarctica's unique location at the bottom of the
world and the unique weather conditions that exist
Antarctica
Area: total: 14 million sq km
land: 14 million sq km (280,000 sq km ice-free,
13.72 million sq km ice-covered) (est.)
note: fifth-largest continent, following Asia, Africa,
North America, and South America, but larger than
Australia and the subcontinent of Europe
Rank: 7
Physical properties
Further information: Sea water
The area of the World Ocean is 361×106 km2 (139×106 mi2)[6]
Its volume is approximately 1.3 billion cubic kilometres (310
million cu mi).[7] This can be thought of as a cube of water with
an edge length of 1,111 kilometres (690 mi). Its average depth
is 3,790 metres (12,400 ft), and its maximum depth is
10,923 metres (6.787 mi)[6] Nearly half of the world's marine
waters are over 3,000 metres (9,800 ft) deep.[3] The vast
expanses of deep ocean (anything below 200 metres (660 ft)
cover about 66% of the Earth's surface.[8] This does not include
seas not connected to the World Ocean, such as the Caspian
Sea.
The total mass of the hydrosphere is about
1,400,000,000,000,000,000 metric tons (1.5×1018 short tons) or
1.4×1021 kg, which is about 0.023% of the Earth's total mass.
Less than 3% is freshwater; the rest is saltwater, mostly in the
ocean.
Assuming the average thickness of the ice in
Antarctica is 7000 feet estimate the sea level
rise if all the ice melted.