CHAPTER 3 The Experimental Basis of Quantum Physics 3.1 Discovery of the X Ray and the Electron 3.2 Determination of Electron Charge 3.3 Line Spectra 3.4 Quantization 3.5 Blackbody Radiation 3.6 Photoelectric Effect 3.7 X-Ray Production 3.8 Compton Effect 3.9 Pair Production and Annihilation
CHAPTER 4 Structure of the Atom 4.1 The Atomic Models of Thomson and Rutherford 4.2 Rutherford Scattering 4.3 The Classic Atomic Model 4.4 The Bohr Model of the Hydrogen Atom 4.5 Successes and Failures of the Bohr Model 4.6 Characteristic X-Ray Spectra and Atomic Number 4.7 Atomic Excitation by Electrons Bohr’s different; he’s a football [U.S. soccer] player! Ernest Rutherford, giving an uncharacteristic compliment to a theorist-Niels Bohr in this case.
Thomson’s Atomic Model Thomson’s “plum-pudding” model of the atom had the positive charges spread uniformly throughout a sphere the size of the atom with, the newly discovered “negative” electrons embedded in the uniform background. In Thomson’s view, when the atom was heated, the electrons could vibrate about their equilibrium positions, thus producing electromagnetic radiation. Does it really look like this? How do we study this???
Response functions j = sE (V=IR) (Linear) Response function Investigation Action (Input) Reaction (Response) How is this guy? j = sE (V=IR) x = (1/k) F P = cE E M = cM H R = c H (Linear) Response function Input Response
Examples hv e - q Z X Y f “Pin hole” ARPES
Scattering Exp 1 2 3 1 : Incident particles : photon (all kinds), electron, neutron, etc 2 : Analyzer measures the angle of the scattered particle 3 : Detector counts # of scattered particles (intensity) Intensity as a function of angle
Rutherford Scattering Intensity as a function of angle Differential cross section 𝑑𝜎 𝑑Ω Contains useful information
Experiments of Geiger and Marsden
Diffractometer & Detector Geiger-Muller tube
The Hydrogen Atom and Transition
Characteristic X-ray Spectra & transitions
X-ray emission energies Moseley plot http://xdb.lbl.gov Moseley’s formula