Chem 125 Lecture 3 9/9/02 Projected material

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Chem 125 Lecture 39/9/02Projected material
This material is for the exclusive use of Chem
125 students at Yale and may not be copied or
distributed further. It is not readily
understood without reference to notes from the
lecture.
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Equilibrium vs. Resonance
One Real Species Two Reasonable Structural
Formulas
Two Real Species
Failure of Simplistic Notation
Unusually Stable
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Unusually Stable?
Compared to What?
a question second in importance only to How do
you know?
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Equilibrium vs. Resonance
LORE
Two Species
Two Species
One Nuclear Geometry!
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OCCULT CHEMISTRYA SERIES OFClairvoyant
Observations on theChemical ElementsBYANNIE
BESANT, P.T.S.ANDCHARLES W.
LEADBEATERReprinted from the
Theosophist.THEOSOPHIST OFFICE, ADYAR,
MADRAS, S.THEOSOPHICAL PUBLISHING SOCIETY,
LONDON AND BENARES CITY.
1909 (105 pp.) 1919 (123 pp.)
1951 (400 pp.)
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Benzene(1924)
"each of the three valencies of each Carbon
are satisfied by Hydrogen, and the fourth
valency, which some have postulated as going to
the interior of the molecule, does actually do
so."
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Benzene Resonance
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The Occult Chemists (1895-1932)
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Were They Crackpots or Charlatans?
"These 1905 chemical weights differ from those
hitherto accepted, and are generally lighter than
those given in earlier textbooks. It is
interesting to note that our counting endorses
the earlier numbers... we must wait to see if
later observations will endorse the last results
of orthodox chemistry, or confirm ours."
Exact hits on 10 of 15 elements!
Chance of innocent exact hit on 10 of 60 is
1/10,000,000,000,000
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Innocent Subconscious Adjustment?
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Innocent Subconscious Adjustment?
a) 4 (4 15 8 3)
b) 16 (4 6 9)
c) 2 (12 7 6 2 5)
d) 2 2 (4 4 4 6)
e) 2 12 (28 4 11 3 3 6 2 4)
Grand Total 3546
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gt100,000 atoms hydrogen!
25 nm (250 Å)
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Science, 11 August 2000
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Scanning Tunneling Microscopy (1981)
Gerd Binnig
Heinrich Rohrer
Nobel Prize (1986)
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Cantilever Choice
Only one of these five cantilevers is used in any
one experiment. They differ in stiffness and
ability to twist.
The smallest scale division is 20 mm
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Scanning Electron MicrographsofAFM Cantilever
Tip
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COOH tip
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Scanning Tunneling Microscopy (1999)
Br(CH2)11COOH on graphite
O
Br
Geo. Flynn D. Yablon (Columbia Univ)
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Quantum corral
Fe atoms on Cu
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SNOM
Scanning Near-Field Optical Microscope
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Wm. Lawrence Bragg(1890-1971)
Determined structure of ZnS from Laue's X-ray
photograph (1912)
Youngest Nobel Laureate (1915)