1. Introduction.- 2. Lattice Distortion and the Jahn-Teller Effect.- 2.1 The Electron-Phonon Interaction.- 2.1.

1 The Born-Oppenheimer and Related Adiabatic Approximations.- 2.1.2 Electron-Lattice Coupling.- 2.1.3 Occupancy Levels and One-Electron Eigenvalues.- 2.

2 Symmetry Considerations: The Stable Atomic Configurations.- 2.2.1 General Reduction of the Jahn-Teller Matrices in Td Symmetry.- 2.2.2 The Stable Distortions.- a) The Nondegenerate A1 (or A2) Level.

- b) The Twofold Degenerate Level E.- c) The Triply Degenerate State T Coupled to E Modes.- d) The Triply Degenerate State Coupled to E and T Modes.- 2.2.3 The Case of Near Degeneracy.- 2.3 Coupled Electronic and Nuclear Motion: Vibronic States -- Static and Dynamic Jahn-Teller Limits.

- 2.3.1 The E State Coupled to E Modes (Case of Cylindrical Symmetry).- 2.3.2 Static and Dynamic Jahn-Teller Effects.- a) The Static Limit.- b) The Dynamic Limit.

- 2.3.3 The Ham Effect.- 2.3.4 Extension to More Complex Cases.- a) T2 Level with T2 Modes.- b) E Level with E Modes.

- 2.3.5 Transitions from Static to Dynamic Situations.- 2.4 The Vacancy in Silicon.- 2.4.1 Static Distortions Near the Vacancy.

- 2.4.2 The Relative Importance of the Many-Electron Effects and the Jahn-Teller Effect.- 2.4.3 Effective Force Constants Near the Vacancy.- 2.4.

4 The Negative U Center Formed by V++, V+, V0, in Silicon.- 3. Electron Paramagnetic Resonance.- 3.1 The Hamiltonian.- 3.2 Electronic Zeeman Interaction.- 3.

2.1 Zeeman Interaction.- 3.2.2 Spin Resonance.- 3.2.3 Observation of Resonance.

- 3.3 Spin Orbit Coubling.- 3.3.1 Quenching of Orbital Motion.- 3.3.2 Effective Spin Hamiltonian.

- 3.3.3 Quantitative Treatment of the g Tensor.- 3.3.4 Analysis of the g Tensor.- 3.4 Hyperfine Interaction.

- 3.5 Nuclear Zeeman Interaction -- Double Resonance.- 3.6 Spin-Spin Interaction. Fine Structure.- 3.7 EPR of Impurities and Vacancy -- Impurity Pairs in Silicon.- 3.

7.1 Evaluation of the g Shift.- 3.7.2 The Hyperfine Tensor.- 3.7.3 Experimental Results.

- 3.8 The Vacancy in Silicon.- 3.8.1 EPR Spectrum for V+.- 3.8.2 Microscopic Model for V+.

- 3.8.3 Charge States of the Vacancy.- 3.8.4 Jahn-Teller Distortion.- 3.8.

5 Energy Levels.- 4. Optical Properties.- 4.1 Transition Probability.- 4.2 The Configuration Coordinate Diagram.- 4.

3 Optical Line Shape and the Electron-Lattice Interaction.- 4.3.1 Coupling to One Lattice Coordinate at T = 0 K.- 4.3.2 Overlap Between Harmonic Oscillators.- 4.

3.3 The Low-Temperature Limit.- 4.3.4 The Strong Coupling Limit.- 4.3.5 Classical Treatment for the Lattice.

- 4.3.6 Coupling to a Continuum of Lattice Modes.- 4.3.7 Moments of the Line-Shape Function.- 4.4 Optical Cross Section.

- 4.4.1 Theoretical Models.- 4.4.2 Exact Expression for the Case of a Delta-Function Potential.- 4.4.

3 Measurement.- 4.5 An Example. The GR Absorption Band in Diamond.- 4.5.1 Experimental Situation.- 4.

5.2 Theoretical Interpretation.- 5. Electrical Properties.- 5.1 Carrier Distribution Between Bands and Defect Levels.- 5.1.

1 Intrinsic Semiconductor.- 5.1.2 Extrinsic Semiconductor.- 5.1.3 The Degeneracy Factor.- 5.

1.4 Experimental Determination of Defect Concentration.- 5.2 Conduction in Case of Defect Interaction.- 5.2.1 Metallic Conduction.- 5.

2.2 Hopping Conduction.- a) Jump Probability.- b) Hopping Conductivity.- 5.2.3 Observation of Hopping Conductivity.- 5.

3 Carrier Scattering.- 5.3.1 Scattering Cross Section.- 5.3.2 Mobility.- a) Scattering by a Charged Center.

- b) Scattering by Pairs.- c) Scattering by Neutral Defects.- 5.3.3 Experimental Results.- 6. Carrier Emission and Recombination.- 6.

1 Emission and Capture Rates.- 6.1.1 The Principle of Detailed Balance.- 6.1.2 Enthalpy and Entropy of Ionization.- 6.

1.3 Trapping and Recombination Centers.- 6.2 Experimental Observation of Emission Rates.- 6.2.1 Principle.- 6.

2.2 Observation Techniques.- 6.2.3 Emission from Minority and Majority Carrier Traps.- 6.2.4 Capture and Reemission from Majority Carrier Traps.

- 6.2.5 Exact Theory.- 6.2.6 Deep Level Transient Spectroscopy.- 6.2.

7 Admittance Spectroscopy.- 6.3 Nonradiative Recombination Processes.- 6.3.1 Auger Processes.- 6.3.

2 Cascade Capture.- 6.3.3 Carrier Capture by Multiphonon Emission.- 6.4 Experimental Determination of Ionization Energies, Entropies and Cross Sections.- 6.4.

1 Capture Cross Section.- 6.4.2 Experimental Determination of Ionization Energies and Entropies.- 6.4.3 DLTS Observation of a Negative U Center: The Vacancy in Silicon.- 6.

5 Influence of the Electric Field on Emission Rates.- 6.5.1 The Frenkel-Poole Effect.- 6.5.2 Tunnelling Effect.- 6.

5.3 Phonon-Assisted Tunnel Emission.- 7. Other Methods of Detection.- 7.1 Photoexcitation.- 7.1.

1 Principle.- 7.1.2 Shockley-Read Recombination.- 7.1.3 Photoconductivity.- 7.

1.4 Spin-Dependent Recombination.- 7.1.5 An Example: Photoconductivity of Boron in Diamond.- 7.2 Optical Detection of Paramagnetic Resonance.- 7.

2.1 Principle of the Technique.- 7.2.2 ODMR of Deep Donor-Acceptor Pairs.- 7.3 Direct Detection of Phonons.- 7.

3.1 Calorimetric Absorption.- 7.3.2 Photoacoustic Spectroscopy.- 8. Defect Production by Irradiation.- 8.

1 Interaction of Radiation with Solids.- 8.1.1 General Formalism.- 8.1.2 Dynamics of a Collision.- 8.

1.3 Differential Scattering Cross Section.- a) Hard Sphere Collision.- b) Rutherford Scattering.- 8.2 Defect Production.- 8.2.

1 Displacement of the Primary Knock-On Atom.- 8.2.2 Threshold Energy for Atomic Displacement.- 8.2.3 Primary Displacements.- a) Heavy Charged Particles (Ions).

- b) Neutrons.- c) Electrons.- 8.2.4 Secondary Displacements.- 8.3 Defect Nature and Spatial Distribution.- 8.

3.1 Average Number of Defects per Particle.- 8.3.2 Amorphous Layer Formation by Irradiation.- 8.3.3 Range of the Particle.

- 8.4 Experimental Determination of a Threshold Energy.- 8.5 Subthreshold Effects.- 9. Defect Annealing.- 9.1 Annealing Kinetics.

- 9.1.1 Rate of Reaction.- 9.1.2 Order of Reaction.- 9.1.

3 Description in Terms of Chemical Reactions.- 9.1.4 Recombination of Correlated Pairs.- 9.2 Determination of the Annealing Parameters.- 9.2.

1 Rate Constant and Order of Reaction.- 9.2.2 Isothermal Annealing.- 9.2.3 Isochronal Annealing.- 9.

3 Annealing of Defects Induced by Electron Irradiation.- 9.3.1 Stability of the Vacancy-Interstitial Pair.- 9.3.2 Mechanism for Complex Defect Formation.- 9.

3.3 On the Mobility of the Interstitial.- 9.3.4 An Example: The Case of Silicon.- References.