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A. Langmuir(1881-1957)

G. N. Lewis (1875-1946 ). A. Langmuir(1881-1957). M. H. Thatcher ( 1925 – ). K. Blodgett( 1898 –1979 ). Gilbert Newton Lewis (1875 –1946, age71) American physical chemist known for the discovery of the covalent bond ( Lewis dot structures & cubical atom model ),

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A. Langmuir(1881-1957)

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  1. G. N. Lewis (1875-1946) A. Langmuir(1881-1957) M. H. Thatcher(1925 – ) K. Blodgett(1898 –1979)

  2. Gilbert Newton Lewis (1875 –1946, age71) American physical chemist known for the discovery of the covalent bond (Lewis dot structures & cubical atommodel), 2) purification of heavy water (D2O), 3) reformulation of chemical thermodynamics in a mathematically rigorous manner (Fugacity), 4) theory of Lewis acids and bases, 5) photochemical experiments (photon, triplet).

  3. 1) Chemical Bond In 1916(age 41), he published a paper on chemical bonding "The Atom and the Molecule” in which he formulated the idea of covalent bond, consisting of a shared pair of electrons, and he defined the term odd molecule (free radical) when an electron is not shared. He included Lewis dot structures as well as the cubical atom model. These ideas on chemical bonding were expanded upon by Irving Langmuir and became the inspiration for the studies on the nature of the chemical bond by Linus Pauling.

  4. 1) Chemical Bond In 1916(age 41), he published a paper on chemical bonding "The Atom and the Molecule” in which he formulated the idea of covalent bond, consisting of a shared pair of electrons, and he defined the term odd molecule (free radical) when an electron is not shared. He included Lewis dot structures as well as the cubical atom model. These ideas on chemical bonding were expanded upon by Irving Langmuir and became the inspiration for the studies on the nature of the chemical bond by Linus Pauling.

  5. 4) Lewis Acid & Base In 1923(age 48), he formulated the electron-pair theory of acid-base reactions. In the so-called Lewis theory of acids and bases, a "Lewis acid" is an electron-pair acceptor and a "Lewis base" is an electron-pair donor. Great Concept In Chemistry: Lewis acid&base, Brønstedacid&base, Pearson’s HSAB

  6. 6) He was a professor of chemistry at MIT (age 36), and the University of California, Berkeley (age 37). Although he never won the award he was nominated for a Nobel Prize 35 times. Why he was not able to get-----????? SeeWikipedia encyclopedia ● G. N. Lewis vs. V. Nernst (1920, Nobel Prize in chemistry, thermodynamics) ● His studentHarold Urey (1934 Nobel Prize in chemistry, the discovery of deuteriumD2) ● His posdocGlenn T.Seaborg(1951 Nobel Prize in Chemistry, discovery of the transuranium elements) ● Irving Langmuir (1932 Nobel Prize in Chemistry, Discoveries and investigations in surface chemistry )

  7. 6) Death & Mystery In 1946, a graduate student found Lewis's lifeless body under a laboratory workbench at Berkeley. Lewis had been working on an experiment with liquid hydrogen cyanide (HCN), and deadly fumes from a broken line had leaked into the laboratory. However, some believe that it may have been a suicide. ●Why ? ●Why he did not win the Nobel Award even was nominated so many times? SeeWikipedia encyclopedia(G. N. Lewis vs. V. Nernst, His student )

  8. If Lewis's death was indeed a suicide, a possible explanation was depression brought on by a lunch with Irving Langmuir. Langmuir and Lewis had a long rivalry, dating back to Langmuir's extensions of Lewis's theory of the chemical bond.

  9. Langmuir had been awarded the 1932 Nobel Prize in chemistry for his work on surface chemistry, while Lewis had not received the Prize despite having been nominated 35 times. On the day of Lewis's death, Langmuir and Lewis had met for lunch at Berkeley, a meeting that Michael Kasha recalled only years later. Associates reported that Lewis came back from lunch in a dark mood, played a morose game of bridge with some colleagues, then went back to work in his lab. An hour later, he was found dead. Langmuir's papers at the Library of Congress confirm that he had been on the Berkeley campus that day to receive an honorary degree.

  10. 2-1) D2O & Nobel Prize In 1913 (age 38), he was elected to the National Academy of Sciences. He resigned in 1934(age 59), refusing to state the cause for his resignation. His decision to resign may have been sparked by resentment over the award of the 1934 Nobel Prize for chemistry to his student, Harold Urey, for the discovery of deuterium (D2), a prize Lewis almost certainly felt he should have shared for his work on purification and characterization of heavy water ( Lewis was the first to produce a pure sample of D2O in 1933 (age 58)).

  11. 2-2) By accelerating deuterons (deuterium nuclei) in Ernest O. Lawrence‘s cyclotron, Lewis was able to study many of the properties of atomic nuclei. During the 1930s, he was mentor to Glenn T.Seaborg, who was retained for post-doctoral work as Lewis’ personal research assistant. Seaborg went on to win the 1951 Nobel Prize in Chemistry for the "discoveries in the chemistry of the transuranium elements” 93Np-102No, 106Sg (seaborgium)

  12. 第四遷移元素 アクチノイド系21元素(89Ac~111Rg)

  13. Irving Langmuir (1881 –1957 age 76) American chemist and physicist. His most noted publication (1919, age 38) was the famous article "The Arrangement of Electrons in Atoms and Molecules”. He outlined his "concentric theory of atomic structure building on Lewis's cubical atom theory and W. Kossel's chemical bonding theory “.

  14. 2) While at General Electric [1909–1950(age 28-69)], Langmuir advanced several basic fields of physics and chemistry and surface science, invented the gas-filled incandescent lamp and the hydrogen welding technique. ● improvement of the diffusion pump ● invention of the high-vacuum tube. ● discovery: filling the bulb with an inert gas such as argon lengthen the lifetime of a tungsten filament. ● discovery:atomic hydrogen→invent the atomic hydrogen welding process (the first plasma weld ).

  15. 3-1) His surface chemistry began at this point, when he discovered that molecular hydrogen introduced into a tungsten- filament bulb dissociated into atomic hydrogen and formed a layer one atom thick on the surface of the bulb. 3-2) In 1917 (age 36), he published a paper on the chemistry of oil films. He theorized that the hydrophilic group down in the water and the hydrophobic chains clumped together on the surface with one molecule thick. air water

  16. 3-3)He joined Katharine B. Blodgett to study thin films and surface adsorption. They introduced the concept of a monolayer and the two-dimensional physics which describe such a surface. In 1932 he received the Nobel Prize in Chemistry "for his discoveries and investigations in surface chemistry.“

  17. Katharine Burr Blodgett (1898 –1979 age 81) ●The first woman to work as a scientist for General Electric Lab. in New York. ● The first woman to be awarded a Ph.D. in Physics from University of Cambridge. 1) During her research, she often worked with Langmuir, who had worked with her father. They worked on monomolecularcoatings designed to cover surfaces of water, metal, or glass. 2) In 1938 (age 40), she devised a method to spread these monomolecular coatings one at a time onto glass or metal. This coating is now called the Langmuir-Blodgett film. The Langmuir-Blodgett trough is also named after her.

  18. She also invented the color gauge, a method to measure the molecular coatings on the glass to one millionth of an inch. The "color gauge" employs the concept that different thicknesses of coatings are different colors. She saw that soap bubbles were different colors and discovered that at each place that the soap bubble was a new color, it has a different thickness. She made a glass "ruler" to show different colors corresponding to the thicknesses. Measuring thickness became as simple as matching colors.

  19. Margaret Hilda Thatcher, Baroness Thatcher, (1925-) She was a Prime Minister of the United Kingdom. Originally she was a research chemist before becoming a barrister. Studied chemistry at Somerville College, Oxford. She arrived at Oxford in 1943 and graduated in 1947 (four-year Chemistry Bachelor of Science Degree); she studied Langmuir-Blodgett films, in her final year she specialized in X-ray crystallography under the supervision Of Dorothy Hodgkin (Nobel Prize in Chemistry, vitamin B12).

  20. For grand challenges New great concept and/or method (Lewis acid & base, monolayer, LB method) 2) Fusion of Experiment and Theory (Lewis, Langmuir) 3) Excellent cooperation among supervisors, colleagues, posdocs, and students (Langmuir-Blodgett)

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