Fundamentals of Inelastic Electron Scattering

ISBN-13: 9783211819371 / Angielski / Miękka / 1986 / 186 str.

P. Schattschneider

Opis

Electron energy loss spectroscopy (ELS) is a vast subject with a long and honorable history. The problem of stopping power for high energy particles interested the earliest pioneers of quantum mechanics such as Bohr and Bethe, who laid the theoretical foun- dations of the subject. The experimental origins might perhaps be traced to the original Franck-Hertz experiment. The modern field includes topics as diverse as low energy reflection electron energy loss studies of surface vibrational modes, the spectroscopy of gases and the modern theory of plasmon excitation in crystals. For the study of ELS in electron microscopy, several historically distinct areas of physics are relevant, including the theory of the Debye- Waller factor for virtual inelastic scattering, the use of complex optical potentials, lattice dynamics for crystalline specimens and the theory of atomic ionisation for isolated atoms. However the field of electron energy loss spectroscopy contains few useful texts which can be recommended for students. With the recent appearance of Raether's and Egerton's hooks (see text for references), we have for the first time both a comprehensive review text-due to Raether-and a lucid introductory text which emphasizes experimental aspects-due to Egerton. Raether's text tends to emphasize the recent work on surface plasmons, while the strength of Egerton's book is its treatment of inner shell excitations for microanalysis, based on the use of atomic wavefunctions for crystal electrons.

Spis treści

1. Classical Scattering Theory.- 1.1 Elastic Cross Sections.- 1.2 The Deflection Function.- 1.3 Scattering on a Hard Sphere.- 1.4 The General Case.- 1.5 Rutherford Scattering.- 1.6 Singularities.- 1.7 Inelastic Cross Sections.- 1.8 The Ramsauer-Townsend Effect.- 1.9 On the Validity of the Classical Description.- 2. Quantum Mechanical Scattering Theory.- 2.1 Absorption Edges.- 2.2 The Differential Cross Section.- 2.3 The Dynamic Form Factor.- 2.4 The Generalized Oscillator Strength ..- 2.5 Rutherford Scattering.- 2.6 The Bethe Differential Cross Section.- 2.7 The Hydrogenic Approach.- 2.8 The Bethe Approximation.- 2.9 Zonal Harmonics Expansion.- 2.10 Qualitative Interpretation.- 2.11 The Total Elastic Cross Section.- 2.12 The Ramsauer-Townsend Effect.- 3. Practical Aspects of Absorption Edge Spectroscopy.- 3.1 A Survey of Applications.- 3.2 Microanalysis.- 3.3 Electron Compton Scattering.- 3.4 Site-specific Excitations.- 3.5 Extended Energy Loss Fine Structure (EXELFS).- 4. Electrodynamics in Homogeneous, Isotropic Media.- 4.1 Fourier Transform.- 4.2 Linear Response of a Medium.- 4.3 The Maxwell Equations.- 4.4 The Dielectric Function.- 4.5 The Drude Model.- 4.6 Charge Oscillations in a Metal.- 5. Some Details on Charge Oscillations.- 5.1 Screening.- 5.2 Plasmons.- 5.3 Plasmon Dispersion.- 5.4 Boundaries.- 5.5 Surface Oscillations.- 5.6 The ATR-Method.- 5.7 On the Restricted Validity of the Fresnel Equations.- 5.8 The Differential Cross Section.- 5.9 Energy Loss Function.- 6. Quantum Mechanical Preliminaries.- 6.1 Summary of Important Facts.- 6.2 The Lippman-Schwinger Equation.- 6.3 The Green Operator.- 6.4 The Dyson Equation.- 6.5 Green Operators in the Time Domain.- 6.6 Relation of G0 to the Time Evolution Operator.- 6.7 Second Quantization.- 6.8 Operators in Second Quantization.- 6.9 The Perturbation Series in Graphical Representation.- 6.10 An Example.- 6.11 The Coulomb Interaction.- 7. Quantum Mechanical Description of the Electron Gas.- 7.1 The Jellium Hamiltonian.- 7.2 Sommerfeld Non-interacting e--Gas.- 7.3 Hartree Approximation (HA).- 7.4 Hartree-Fock Approximation (HFA).- 7.5 Why Higher Order Perturbation Theory Does not Work.- 7.6 The Random Phase Approximation (RPA).- 7.7 Electron Scattering.- 7.8 Polarization Diagrams.- 8. Beyond Simple Models.- 8.1 Solid State Effects.- 8.2 Ion-Electron Interactions.- 8.3 Multiple Scattering.- References.- Author Index.