IN view of the growing interest in spectroscopy at radio and micro wave frequencies, and the increasing number of its applications to both physics and chemistry, it was thought that a general outline of the subject for non-specialists might be of some value. Research in this field is still expanding, but is now sufficiently developed for a critical review to be made both of its main applications and of the techniques that are used in this wavelength region. A broad approach has been taken, and the similarity and inter relation of the different branches have been stressed, as well as their general setting in spectroscopy as a whole. In this way it is hoped that the book will be of interest to many research workers and students who, although not directly concerned with the subject, would like to obtain a general picture of its methods and applica tions. At the same time considerable space has been given to the design of experimental apparatus and equipment, so that those wishing to set up such spectroscopes should be able to find much useful and detailed information.
1. Introduction.- 1.1 The nature of spectroscopy.- 1.2 The concept of energy levels.- 1.3 The electromagnetic spectrum.- 1.4 Methods of spectroscopy.- 1.5 The microwave region.- 1.6 Gaseous spectroscopy.- 1.7 Solid state spectroscopy.- 1.8 Ferromagnetic resonance.- 1.9 Free radicals and F-centres.- 1.10 Measurements at radiofrequencies.- 2. The Production and Detection of Microwaves.- 2.1 Introduction.- 2.2 Velocity modulation.- 2.3 Practical microwave sources.- 2.4 Automatic tuning.- 2.5 Other sources of radiation.- 2.6 Detection of the radiation—silicon crystals.- 2.7 Different detecting systems.- 2.8 Display systems.- 2.9 Measurement of frequency.- 3. Waveguide Techniques.- 3.1 Propagation of radiation in waveguides.- 3.2 Choice of waveguide size.- 3.3 Circular guides.- 3.4 Coupling into waveguides. Directional couplers.- 3.5 Matching techniques.- 3.6 Crystal holders.- 3.7 Microwave bridge balancing.- 3.8 Cavity resonators. Wavemeters.- 3.9 Absorption cavities.- 3.10 Waveguide cells.- 4. Microwave Spectroscopes.- 4.1 General considerations.- 4.2 Line widths in gaseous spectroscopy—natural line width—the Doppler effect—pressure broadening—wall collisions—power saturation broadening—modulation broadening.- 4.3 Early gaseous microwave spectroscopes—Stark modulation—source modulation.- 4.4 Recent gaseous spectroscopes—mm-wavelength spectroscope—high resolution gaseous spectroscope.- 4.5 Comparison of sensitivities—superheterodyne detection —Stark and source modulation—crystal video detection.- 4.6 Special spectroscopes. Zeeman effect.- 4.7 Measurement of line shapes and intensities.- 4.8 Paramagnetic resonance. Solid state spectroscopy— natural line width—spin-lattice relaxation—spin-spin interaction—exchange interaction—power saturation broadening—inhomogeneous fields—summary.- 4.9 Early paramagnetic resonance experiments.- 4.10 Typical paramagnetic resonance spectroscopes— crystal-video—superheterodyne detection—source modulation.- 4.11 Gaseous paramagnetic spectroscopes.- 4.12 Comparison of sensitivities.- 4.13 The production and measurement of magnetic fields.- 4.14 Low-temperature technique.- 5. Results and Theory of Gaseous Spectroscopy.- 5.1 Introduction—water vapour—oxygen.- 5.2 Molecular energy levels.- 5.3 Linear molecules.- 5.4 Symmetric-top molecules.- 5.5 Asymmetric-top molecules.- 5.6 Inversion spectra.- 5.7 Hindered rotation.- 5.8 Stark and Zeeman effects—Introduction.- 5.9 Stark effect—linear molecules—symmetric-top molecules— asymmetric-top molecules—inversion spectra.- 5.10 The Zeeman effect.- 5.11 Nuclear interaction and hyperfine structure—electric quadrupole interaction—two-nuclei quadrupole interaction— nuclear octopole moment—magnetic hyperfine structure.- 6. Results and Theory of Paramagnetic Resonance.- 6.1 Introduction.- 6.2 The transition elements.- 6.3 The effect of internal crystalline fields.- 6.4 The resonance condition.- 6.5 Nuclear interaction and hyperfine structure.- 6.6 Second-order effects and quadrupole interaction.- 6.7 The theoretical Hamiltonian.- 6.8 Angular variation—electronic transitions—hyperfine structure.- 6.9 The iron group. Effect of crystalline fields.- 6.10 General results from the iron transition group— electronic transitions—hyperfine structure.- 6.11 Results for individual ions of the first transition group.- 6.12 Covalent compounds.- 6.13 The rare-earth group. General results.- 6.14 Results for different ions of the rare-earth group.- 6.15 Results from the palladium transition group.- 6.16 Results for the platinum group.- 6.17 Results from the trans-uranic group.- 6.18 Paramagnetic resonance and other low-temperature measurements.- 6.19 Paramagnetic resonance in gases.- 6.20 Conclusion.- 7. Ferromagnetic Resonance. Free Radicals and F-Centres.- 7.1 Introduction—ferromagnetic resonance—paramagnetic resonance in free radicals—electron resonance from metals and semi-conductors—paramagnetic resonance absorption in F-centres.- 7.2 Ferromagnetic resonance. Initial work.- 7.3 Further experiments in ferromagnetic resonance.- 7.4 The theoretical treatment of ferromagnetic resonance —g-values—line widths.- 7.5 Antiferromagnetic resonance.- 7.6 Paramagnetic resonance in systems other than the transition elements.- 7.7 Resonance in free radicals.- 7.8 Resonance from broken bonds.- 7.9 Resonance from conduction electrons.- 7.10 Electron resonance in semi-conductors—resonance from donor atoms in silicon—cyclotron resonance in germanium.- 7.11 Paramagnetic resonance from F-centres.- 7.12 Summary.- 8. Radiofrequency Spectroscopy.- 8.1 The resonance condition.- 8.2 Molecular beam experiments—steady field deflexion methods—radiofrequency resonance techniques—initial results from the resonance method—recent work on molecular beams.- 8.3 Atomic beams and the determination of the free electron gyromagnetic ratio—the hyperfine structure anomaly—the determination of quadrupole moments— determination of the gyromagnetic ratio of the free electron.- 8.4 Initial solid state experiments.- 8.5 The techniques of nuclear resonance.- 8.6 The techniques of nuclear induction.- 8.7 Pulse and echo methods—nutational resonance—spin echo method.- 8.8 Results of nuclear paramagnetic experiments— results from liquids—results from metals—results from crystals—other frequency shifts in nuclear resonance.- 8.9 Pure quadrupole nuclear resonance—initial work— later results—experimental technique.- 8.10 The interaction of electron and nuclear resonance. The Overhauser effect.- 8.11 Electron resonance at radiofrequencies.- 9. Applications of Radiofrequency and Microwave Spectroscopy.- 9.1 Introductory review.- I: Applications to Fundamental Research.- 9.2 Nuclear spins—determinations by paramagnetic resonance —determination by gaseous spectroscopy—determination by nuclear resonance.- 9.3 Nuclear magnetic moments—from nuclear resonance— from paramagnetic resonance—determinations from gaseous spectroscopy.- 9.4 Nuclear quadrupole moments.- 9.5 Nuclear alignment—low-temperature methods—paramagnetic resonance and nuclear alignment—results of low-temperature experiments—nuclear alignment by direct resonance techniques.- 9.6 The determination of chemical parameters—determinations from gaseous spectroscopy—determinations from paramagnetic resonance—determinations from nuclear resonance.- II: Applications of a Practical Nature.- 9.7 Frequency standards and the measurement of time— gaseous microwave standards—atomic beam frequency standards.- 9.8 The measurement of magnetic fields—nuclear resonance—electron resonance—nuclear precession—stabilization of magnetic fields by resonance methods.- 9.9 Chemical analysis—by gaseous spectroscopy—by paramagnetic resonance.- 9.10 The detection of free radicals.- 9.11 The study of irradiation damage.- 9.12 Other applications—radio astronomy—study of conduction bands in metals and semi-conductors—photochemical reactions—study of gas discharges.- Author Index.
IN view of the growing interest in spectroscopy at radio and micro wave frequencies, and the increasing number of its applications to both physics and chemistry, it was thought that a general outline of the subject for non-specialists might be of some value. Research in this field is still expanding, but is now sufficiently developed for a critical review to be made both of its main applications and of the techniques that are used in this wavelength region. A broad approach has been taken, and the similarity and inter relation of the different branches have been stressed, as well as their general setting in spectroscopy as a whole. In this way it is hoped that the book will be of interest to many research workers and students who, although not directly concerned with the subject, would like to obtain a general picture of its methods and applica tions. At the same time considerable space has been given to the design of experimental apparatus and equipment, so that those wishing to set up such spectroscopes should be able to find much useful and detailed information.
1. Introduction.- 2. The Production and Detection of Microwaves.- 3. Waveguide Techniques.- 4. Microwave Spectroscopes.- 5. Results and Theory of Gaseous Spectroscopy.- 6. Results and Theory of Paramagnetic Resonance.- 7. Ferromagnetic Resonance. Free Radicals and F-Centres.- 8. Radiofrequency Spectroscopy.- 9. Applications of Radiofrequency and Microwave Spectroscopy.- Author Index.
Inhaltsverzeichnis
1. Introduction.- 2. The Production and Detection of Microwaves.- 3. Waveguide Techniques.- 4. Microwave Spectroscopes.- 5. Results and Theory of Gaseous Spectroscopy.- 6. Results and Theory of Paramagnetic Resonance.- 7. Ferromagnetic Resonance. Free Radicals and F-Centres.- 8. Radiofrequency Spectroscopy.- 9. Applications of Radiofrequency and Microwave Spectroscopy.- Author Index.
Klappentext
IN view of the growing interest in spectroscopy at radio and micro wave frequencies, and the increasing number of its applications to both physics and chemistry, it was thought that a general outline of the subject for non-specialists might be of some value. Research in this field is still expanding, but is now sufficiently developed for a critical review to be made both of its main applications and of the techniques that are used in this wavelength region. A broad approach has been taken, and the similarity and inter relation of the different branches have been stressed, as well as their general setting in spectroscopy as a whole. In this way it is hoped that the book will be of interest to many research workers and students who, although not directly concerned with the subject, would like to obtain a general picture of its methods and applica tions. At the same time considerable space has been given to the design of experimental apparatus and equipment, so that those wishing to set up such spectroscopes should be able to find much useful and detailed information.
