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Lecture #5, Shell Model, Emissions Spectra, Quantum Numbers

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Lecture #5, Shell Model, Emissions Spectra, Quantum Numbers Welcome to 3.091 Lecture 5 September 18, 2009 Electron Shell Model & Quantum Numbers 3.091 Periodic Table Quiz 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 Name Grade /10 Image by MIT OpenCourseWare. PrismFigure 6.9 Spectrograph A.A. Ångström (1853) spectrum of atomic H, not H2 Electronic emission transition Higher-Energy Orbit e- Photon e- Lower-Energy Orbit Image by MIT OpenCourseWare. Bohr Postulates for the Hydrogen Atom 1. Rutherford atom is correct 2. Classical EM theory not applicable to orbiting e- 3. Newtonian mechanics applicable to orbiting e- 4. Eelectron = Ekinetic + Epotential 5. e- energy quantized through its angular momentum: L = mvr = nh/2π, n = 1, 2, 3,… - 6. Planck-Einstein relation applies to e transitions: ΔE = Ef - Ei = hν = hc/λ c = νλ Figure 6.11 (a) Balmer Series Transitions (b) Electronic emission transition n = 5 n = 6 n = 4 n = 3 Higher-Energy Orbit 410 nm e- 434 nm Photon 486 nm e- 656 nm Lower-Energy Orbit n = 2 Image by MIT OpenCourseWare. Figure 6.4a ← E, ν, ν¯ λ → Wavelength , λ (m) (b) 10-12 10-11 10-10 10-9 10-8 10-7 10-6 10-5 10-4 10-3 10-2 10-1 100 101 Gamma X ray Ultraviolet Infrared Microwave Radio 1020 1019 1018 1017 1016 1015 1014 1013 1012 1011 1010 109 108 Frequency , ν (Hz) (a) Visible Spectrum Red Blue Violet Green Yellow Orange 400 450 500 550 600 650 700 Wavelength , λ (nm) Image by MIT OpenCourseWare. Figure 6.12 Lyman Series Balmer Series n = 1 n = 2 Paschen Series n = 3 n = 4 n = 5 Brackett Series n = 6 Pfund Series Image by MIT OpenCourseWare. Bohr Postulates for the Hydrogen Atom 1. Rutherford atom is correct 2. Classical EM theory not applicable to orbiting e- 3. Newtonian mechanics applicable to orbiting e- 4. Eelectron = Ekinetic + Epotential 5. e- energy quantized through its angular momentum: L = mvr = nh/2π, n = 1, 2, 3,… - 6. Planck-Einstein relation applies to e transitions: ΔE = Ef - Ei = hν = hc/λ c = νλ The Nobel Prize in Physics 1925 "for their discovery of the laws governing the impact of an electron upon an atom" Gustav Ludwig Hertz James Franck 1/2 of the prize Germany 1/2 of the prize Germany Halle University Goettingen University Halle, Germany Goettingen, Germany B. 1887 B. 1882 D. 1975 D. 1964 Image by MIT OpenCourseWare. PrismFigure 6.9 Spectrograph A.A. Ångström (1853) spectrum of atomic H, not H2 Image by MIT OpenCourseWare. The Nobel Prize in Physics 1907 "for his optical precision instruments and the spectroscopic and metrological investigations carried out with their aid" Albert Abraham Michelson USA University of Chicago Chicago, lL, USA b. 1852 (in Strelno, then Germany) d. 1931 Image by MIT OpenCourseWare. The Nobel Prize in Physics 1902 "in recognition of the extraordinary service they rendered by their researches into the influence of magnetism upon radiation phenomena" Hendrik Antoon Lorentz Pieter Zeeman 1/2 of the prize 1/2 of the prize the Netherlands the Netherlands Leiden University Amsterdam University Leiden, the Netherlands Amsterdam, the Netherlands b. 1853 b. 1865 d. 1928 d. 1943 Image by MIT OpenCourseWare. The Nobel Prize in Physics 1919 "for his discovery of the Doppler effect in canal rays and the splitting of spectral lines in electric fields" Johannes Stark Germany Greifswald University Greifswald, Germany b. 1874 d. 1957 Image by MIT OpenCourseWare. The Nobel Prize in Physics 1922 "for his services in the investigation of the structure of atoms and of the radiation emanating from them" Niels Henrik David Bohr Denmark Copenhagen University Copenhagen, Denmark b. 1885 d. 1962 Image by MIT OpenCourseWare. © source unknown. All rights reserved. This image is excluded from our Creative Commons license. For more information, see http://ocw.mit.edu/fairuse. Arnold Sommerfeld on the occasion of his 80th birthday Schematic representation of the Stern Gerlach experiment (1921). Substrate Furnace containing molten Ag S µs N Slit Image by MIT OpenCourseWare. no magnetic field divergent magnetic field © source unknown. All rights reserved. This image is excluded from our Creative Commons license. For more information, see http://ocw.mit.edu/fairuse. Z odd The Nobel Prize in Physics 1943 "for his contribution to the development of the molecular ray method and his discovery of the magnetic moment of the proton" Otto Stern USA Carnegie Institute of Technology Pittsburgh, PA, USA b. 1888 (in Sorau, then Germany) d. 1969 Image by MIT OpenCourseWare. Hindenburg HYDROGEN IN B 747 TRANSPORTATION Titanic * built in Germany by Zeppelin (LZ129) * 135 ft in dia. × 804 ft long * 7 million cu ft gas * 112 tons useful lift © source unknown. All rights reserved. This image is excluded from our Creative Commons license. For more information, see http://ocw.mit.edu/fairuse. * Helium Control Act inflated with H2 Hindenburg * 10 transatlantic flights in 1936: 1002 passengers * cruising speed 78 mph * May 6, 1937 arrival of first flight to US © source unknown. All rights reserved. This image is excluded from our Creative Commons license. For more information, see http://ocw.mit.edu/fairuse. * while docking at Lakehurst, NJ © source unknown. All rights reserved. This image is excluded from our Creative Commons license. For more information, see http://ocw.mit.edu/fairuse. © source unknown. All rights reserved. This image is excluded from our Creative Commons license. For more information, see http://ocw.mit.edu/fairuse. * 35 dead of 97 on board * electrical discharge in vicinity of H2 leak * skin of resin (finished with lacquer dope) + aluminum powder + iron oxide on inside sheets of SOLID ROCKET MOTOR grains * end of rigid airships in commercial air transportation * US Navy airship filled with helium (1956) * two-ply cotton envelope could not withstand gasoline fire © source unknown. All rights reserved. This image is excluded from our Creative Commons license. For more information, see http://ocw.mit.edu/fairuse. © source unknown. All rights reserved. This image is excluded from our Creative Commons license. For more information, see http://ocw.mit.edu/fairuse. Vicki! I - I Thought I Heard Your Voice! Roy Lichtenstein (1964) enamel on steel Photo courtesy of action datsun on Flickr. Magnifying Glass Roy Lichtenstein (1963) oil on canvas Photo courtesy of Kyle McDonald on Flickr. MIT OpenCourseWare http://ocw.mit.edu 3.091SC Introduction to Solid State Chemistry Fall 2009 For information about citing these materials or our Terms of Use, visit: http://ocw.mit.edu/terms..
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