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List of the Most Important Symbols Used | |

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Introduction | |

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Classical Physics and Quantum Mechanics | |

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Short Historical Review | |

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The Mass and Size of the Atom | |

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What is an Atom? | |

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Determination of the Mass | |

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Methods for Determining Avogadro's Number | |

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Electrolysis | |

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The Gas Constant and Boltzmann's Constant | |

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X-Ray Diffraction in Crystals | |

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Determination Using Radioactive Decay | |

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Determination of the Size of the Atom | |

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Application of the Kinetic Theory of Gases | |

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The Interaction Cross Section | |

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Experimental Determination of Interaction Cross Sections | |

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Determining the Atomic Size from the Covolume | |

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Atomic Sizes from X-Ray Diffraction Measurements on Crystals | |

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Can Individual Atoms Be Seen? | |

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Problems | |

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Isotopes | |

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The Periodic System of the Elements | |

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Mass Spectroscopy | |

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Parabola Method | |

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Improved Mass Spectrometers | |

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Results of Mass Spectrometry | |

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Modern Applications of the Mass Spectrometer | |

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Isotope Separation | |

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Problems | |

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The Nucleus of the Atom | |

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Passage of Electrons Through Matter | |

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Passage of Alpha Particles Through Matter (Rutherford Scattering) | |

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Some Properties of Alpha Particles | |

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Scattering of Alpha Particles by a Foil | |

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Derivation of the Rutherford Scattering Formula | |

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Experimental Results | |

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What is Meant by Nuclear Radius? | |

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Problems | |

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The Photon | |

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Wave Character of Light | |

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Thermal Radiation | |

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Spectral Distribution of Black Body Radiation | |

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Planck's Radiation Formula | |

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Einstein's Derivation of Planck's Formula | |

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The Photoelectric Effect | |

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The Compton Effect | |

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Experiments | |

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Derivation of the Compton Shift | |

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Problems | |

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The Electron | |

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Production of Free Electrons | |

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Size of the Electron | |

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The Charge of the Electron | |

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The Specific Charge e/m of the Electron | |

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Wave Character of-Electrons and Other Particles | |

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Interferometry with Atoms | |

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Problems | |

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Some Basic Properties of Matter Waves | |

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Wave Packets | |

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Probabilistic Interpretation | |

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The Heisenberg Uncertainty Relation | |

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The Energy-Time Uncertainty Relation | |

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Some Consequences of the Uncertainty Relations for Bound States | |

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Problems | |

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Bohr's Model of the Hydrogen Atom | |

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Basic Principles of Spectroscopy | |

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The Optical Spectrum of the Hydrogen Atom | |

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Bohr's Postulates | |

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Some Quantitative Conclusions | |

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Motion of the Nucleus | |

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Spectra of Hydrogen-like Atoms | |

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Muonic Atoms | |

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Excitation of Quantum Jumps by Collisions | |

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Sommerfeld's Extension of the Bohr Model and the Experimental Justification of a Second Quantum Number | |

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Lifting of Orbital Degeneracy by the Relativistic Mass Change | |

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Limits of the Bohr-Sommerfeld Theory. The Correspondence Principle | |

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Rydberg Atoms | |

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Positronium, Muonium, and Antihydrogen | |

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Problems | |

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The Mathematical Framework of Quantum Theory | |

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The Particle in a Box | |

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The Schrï¿½dinger Equation | |

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The Conceptual Basis of Quantum Theory | |

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Observations, Values of Measurements and Operators | |

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Momentum Measurement and Momentum Probability | |

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Average Values and Expectation Values | |

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Operators and Expectation Values | |

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Equations for Determining the Wavefunction | |

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Simultaneous Observability and Commutation Relations | |

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The Quantum Mechanical Oscillator | |

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Problems | |

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Quantum Mechanics of the Hydrogen Atom | |

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Motion in a Central Field | |

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Angular Momentum Eigenfunctions | |

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The Radial Wavefunctions in a Central Field * | |

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The Radial Wavefunctions of Hydrogen | |

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Problems | |

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Lifting of the Orbital Degeneracy in the Spectra of Alkali Atoms | |

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Shell Structure | |

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Screening | |

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The Term Diagram | |

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Inner Shells | |

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Problems | |

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Orbital and Spin Magnetism. Fine Structure | |

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Introduction and Overview | |

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Magnetic Moment of the Orbital Motion | |

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Precession and Orientation in a Magnetic Field | |

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Spin and Magnetic Moment of the Electron | |

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Determination of the Gyromagnetic Ratio by the Einstein-de Haas Method | |

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Detection of Directional Quantisation by Stern and Gerlach | |

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Fine Structure and Spin-Orbit Coupling: Overview | |

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Calculation of Spin-Orbit Splitting in the Bohr Model | |

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Level Scheme of the Alkali Atoms | |

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Fine Structure in the Hydrogen Atom | |

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The Lamb Shift | |

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Problems | |

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Atoms in a Magnetic Field: Experiments and Their Semiclassical Description | |

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Directional Quantisation in a Magnetic Field | |

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Electron Spin Resonance | |

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The Zeeman Effect | |

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Experiments | |

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Explanation of the Zeeman Effect from the Standpoint of Classical Electron Theory | |

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Description of the Ordinary Zeeman Effect by the Vector Model | |

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The Anomalous Zeeman Effect | |

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Magnetic Moments with Spin-Orbit Coupling | |

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The Paschen-Back Effect | |

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Double Resonance and Optical Pumping | |

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Problems | |

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Atoms in a Magnetic Field: Quantum Mechanical Treatment | |

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Quantum Theory of the Ordinary Zeeman Effect | |

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Quantum Theoretical Treatment of the Electron and Proton Spins | |

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Spin as Angular Momentum | |

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Spin Operators, Spin Matrices and Spin Wavefunctions | |

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The Schrï¿½dinger Equation of a Spin in a Magnetic Field | |

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Description of Spin Precession by Expectation Values | |

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Quantum Mechanical Treatment of the Anomalous Zeeman Effect with Spin-Orbit Coupling * | |

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Quantum Theory of a Spin in Mutually Perpendicular Magnetic Fields, One Constant and One Time Dependent | |

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The Bloch Equations | |

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The Relativistic Theory of the Electron. The Dirac Equation | |

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Problems | |

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Atoms in an Electric Field | |

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Observations of the Stark Effect | |

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Quantum Theory of the Linear and Quadratic Stark Effects | |

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The Hamiltonian | |

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The Quadratic Stark Effect. | |

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Perturbation Theory Without Degeneracy * | |

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The Linear Stark Effect. | |

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Perturbation Theory in the Presence of Degeneracy * | |

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The Interaction of a Two-Level Atom with a Coherent Radiation Field | |

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Spin and Photon Echoes | |

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A Glance at Quantum Electrodynamics * | |

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Field Quantization | |

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Mass Renormalization and Lamb Shift | |

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Problems | |

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General Laws of Optical Transitions | |

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Symmetries and Selection Rules | |

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Optical Matrix Elements | |

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Examples of the Symmetry Behaviour of Wavefunctions | |

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Selection Rules | |

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Selection Rules and Multipole Radiation * | |

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Linewidths and Lineshapes | |

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Many-Electron Atoms | |

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The Spectrum of the Helium Atom | |

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Electron Repulsion and the Pauli Principle | |

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Angular Momentum Coupling | |

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Coupling Mechanism | |

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LS Coupling (Russell-Saunders Coupling) | |

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jj Coupling | |

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Magnetic Moments of Many-Electron Atoms | |

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Multiple Excitations | |

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Problems | |

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X-Ray Spectra, Internal Shells | |

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Introductory Remarks | |

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X-Radiation from Outer Shells | |

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X-Ray Bremsstrahlung Spectra | |

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Emission Line Spectra: Characteristic Radiation | |

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Fine Structure of the X-Ray Spectra | |

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Absorption Spectra | |

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The Auger Effect | |

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Photoelectron Spectroscopy (XPS), ESCA | |

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Problems | |

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Structure of the Periodic System. Ground States of the Elements | |

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Periodic System and Shell Structure | |

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From the Electron Configuration to the Atomic Term Scheme. Atomic Ground States | |

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Excited States of Atoms and Possible Electronic Configurations. Complete Term Schemes | |

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The Many-Electron Problem. Hartree-Fock Method * | |

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The Two-Electron Problem | |

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Many Electrons Without Mutual Interactions | |

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Coulomb Interaction of Electrons. Hartree and Hartree-Fock Methods | |

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Problems | |

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Nuclear Spin, Hyperfine Structure | |

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Influence of the Atomic Nucleus on Atomic Spectra | |

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Spins and Magnetic Moments of Atomic Nuclei | |

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The Hyperfine Interaction | |

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Hyperfine Structure in the Ground State of the Hydrogen Atom, the Sodium Atom, and the Hydrogen-like Ion <sub>83</sub>Bi<sup>82+</sup> | |

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Hyperfine Structure in an External Magnetic Field, Electron Spin Resonance | |

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Direct Measurements of Nuclear Spins and Magnetic Moments, Nuclear Magnetic Resonance | |

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Applications of Nuclear Magnetic Resonance | |

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The Nuclear Electric Quadrupole Moment | |

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Problems | |

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The Laser | |

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Some Basic Concepts for the Laser | |

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Rate Equations and Lasing Conditions | |

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Amplitude and Phase of Laser Light | |

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Problems | |

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Modern Methods of Optical Spectroscopy | |

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Classical Methods | |

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Quantum Beats | |

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Doppler-tree Saturation Spectroscopy | |

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Doppler-free Two-Photon Absorption | |

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Level-Crossing Spectroscopy and the Hanle Effect | |

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Laser Cooling of Atoms | |

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Nondestructive Single-Photon Detection - An Example of Atomic Physics in a Resonant Cavity | |

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Problems | |

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Progress in Quantum Physics: A Deeper Understanding and New Applications | |

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Introduction | |

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The Superposition Principle, Interference, Probabilily and Probability Amplitudes | |

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Schrï¿½dinger's Cat | |

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Decoherence | |

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Entanglement | |

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The Einstein-Podolsky-Rosen (EPR) Paradox | |

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Bell's Inequalities and the Hidden-Variable Hypothesis | |

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Experiments to Test Bell's Inequalities | |

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Quantum Computers | |

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Historical Remarks | |

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Review of Digital Computers | |

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Basic Concepts of the Quantum Computer | |

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Decoherence and Error Correction | |

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A Comparison Between the Quantum Computer and the Digital Computer | |

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Quantum Information Theory | |

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The Bose-Einstein Condensation | |

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Review of Statistical Mechanics | |

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The Experimental Discovery | |

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The Quantum Theory of the Bose-Einstein Condensation | |

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The Atom Laser | |

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Problems | |

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Fundamentals of the Quantum Theory of Chemical Bonding | |

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Introductory Remarks | |

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The Hydrogen-Molecule Ion <$>{\rm H}^{+}_2<$> | |

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The Tunnel Effect | |

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The Hydrogen Molecule H<sub>2</sub> | |

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Covalent-Ionic Resonance | |

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The Hund-Mulliken-Bloch Theory of Bonding in Hydrogen | |

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Hybridisation | |

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The ï¿½ Electrons of Benzene, C<sub>6</sub>H<sub>6</sub> | |

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Problems | |

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Appendix | |

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The Dirac Delta Function and the Normalisation of the Wavefunction of a Free Particle in Unbounded Space | |

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Some Properties of the Hamiltonian Operator, Its Eigenfunctions and its Eigenvalues | |