Lecture 1. Birth of Quantum Mechanics. Historical Background of QM. Experiments, Theories & Student Presentation Engel, Ch. 1 Ratner & Schatz, Ch. 1 Quantum chemistry, D. A. McQuarrie (1983), Ch. 1 Molecular quantum mechanics, Atkins & Friedman (4 th ed. 2005), Ch. 0 Introductory quantum mechanics, R. L. Liboff (4 th ed, 2004), Ch. 2 Experiments are the only means of knowledge at our disposal. The rest is poetry, imagination. - Max Planck -

1885 – Johann Balmer – Line spectrum of hydrogen atoms 1886 – Heinrich Hertz – Photoelectric effect experiment 1897 – J. J. Thomson – Discovery of electrons from cathode rays experiment 1900 – Max Planck – Quantum theory of blackbody radiation 1905 – Albert Einstein– Quantum theory of photoelectric effect 1910 – Ernest Rutherford – Scattering experiment with  -particles 1913 – Niels Bohr – Quantum theory of hydrogen spectra 1923 – A. H. Compton – Scattering experiment of photons off electrons 1924 – Wolfgang Pauli – Exclusion principle – Ch – Louis de Broglie – Matter waves 1925 – Davisson and Germer – Diffraction experiment on wave properties of electrons 1926 – Erwin Schrodinger – Wave equation – Ch – Werner Heisenberg – Uncertainty principle – Ch – Max Born – Interpretation of wave function – Ch. 3 History of QM: Presentation Plan (Final) particle wave

1900 – Max Planck  Quantum theory of blackbody radiation

1900 – Max Planck: Quantum theory of blackbody radiation What is a blackbody radiation? Any example in real life? What is a classical theory for it? What is “UV catastrophe”? What is Planck’s assumption? How did it resolve the dilemma?

1886 – Heinrich Hertz – Photoelectric effect experiment 1897 – J. J. (Joseph John) Thomson – Discovery of electrons 1905 – Albert Einstein– Quantum theory of photoelectric effect 1923 – A. H. Compton – Scattering experiment of photons off electrons

1886 – Heinrich Hertz: Photoelectric effect experiment 1897 – J. J. (Joseph John) Thomson: Discovery of electrons 1905 – Albert Einstein: Quantum theory of photoelectric effect 1910 – Ernest Rutherford –  -particle scattering experiment 1923 – A. H. Compton: Photon-electron scattering experiment What is a photoelectric effect? Any application of the photoelectric effect in real life? What was the dilemma in the photoelectric effect? What is Einstein’s assumption? How did it resolve the dilemma? What is a “scattering”? How did Compton prove Einstein’s theory?

1885 – Johann Balmer – Line spectrum of hydrogen atoms 1913 – Niels Bohr – Theory of atomic spectra

1885 – Johann Balmer – Line spectrum of hydrogen atoms 1913 – Niels Bohr – Theory of atomic spectra What is a “spectrum”? When would you have a “line spectrum”? What was the dilemma in the “line spectrum of an H atom”? What is Bohr’s atom model? How did it resolve the dilemma? * Please remember that people at that time (1913) didn’t know about the de Broglie wavelength (1924) yet. Is it a correct model for an atomic electronic structure?

1924 – Louis de Broglie – Matter waves 1925 – Davisson & Germer – Electron diffraction 1926 – G. P. (George Paget) Thomson – Electron diffraction 1926 – Erwin Schrodinger – Wave equation J. J. Thomson, dad, was awarded the Nobel prize (1906) for showing that the electron is a particle; G.P. Thomson, son, was awarded the Nobel prize (1937) for showing that the electron is a wave.

1924 – Louis de Broglie – Matter waves 1925 – Davisson & Germer – Electron diffraction 1926 – G. P. (George Paget) Thomson – Electron diffraction 1926 – Erwin Schrödinger – Wave equation J. J. Thomson, dad, was awarded the Nobel prize (1906) for showing that the electron is a particle; G.P. Thomson, son, was awarded the Nobel prize (1937) for showing that the electron is a wave. What is the “matter wave” proposed by de Broglie? How does it explain the Bohr’s atom model? What is a “diffraction”? How would an electron diffraction pattern look like if electron is just a particle? Why does the “electron diffraction” prove the de Broglie matter wave? What is the “Schrödinger equation”? How does it compare with a conventional wave equation?