Mössbauer Spectroscopy

Rudolph Mossbauer discovered the phenomenon of recoil-free nuclear resonance fluorescence in 1957-58 and the first indications of hyperfine interactions in a chemical compound were obtained by Kistner and Sunyar in 1960. From these beginnings the technique of Mossbauer spectroscopy rapidly emerged and the astonishing versatility of this new technique soon led to its extensive application to a wide variety of chemical and solid-state problems. This book reviews the results obtained by Mossbauer spectroscopy during the past ten years in the belief that this will provide a firm basis for the continued development and application of the technique to new problems in the future. It has been our aim to write a unified and consistent treatment which firstly presents the basic principles underlying the phenomena involved, then outlines the experimental techniques used, and finally summarises the wealth of experimental and theoretical results which have been obtained. We have tried to give some feeling for the physical basis of the Mossbauer effect with out extensive use of mathematical formalism, and some appreciation of the experimental methods employed without embarking on a detailed discussion of electronics and instrumentation. However, full references to the original literature are provided and particular points can readily be pursued in more detail if required.

1. The Mössbauer Effect -- 1.1 Energetics of free-atom recoil and thermal broadening -- 1.2 Heisenberg natural linewidth -- 1.3 Energy and momentum transfer to the lattice -- 1.4 Recoil-free fraction and Debye-Waller factor -- 1.5 Cross-section for resonant reabsorption -- 1.6 A Mössbauer spectrum -- 2. Experimental Techniques -- 2.1 Velocity modulation of gamma-rays -- 2.2 Constant-velocity drives -- 2.3 Repetitive velocity-scan systems -- 2.4 Derivative spectrometers -- 2.5 Scattering experiments -- 2.6 Source and absorber preparation -- 2.7 Detection equipment -- 2.8 Cryogenic equipment and ovens -- 2.9 Velocity calibration -- 2.10 Curve fitting by computer -- 3. Hyperfine Interactions -- 3.1 Chemical isomer shift,? -- 3.2 Second-order Doppler shift and zero-point motion -- 3.3 Effect of pressure on the chemical isomer shift -- 3.4 Electric quadrupole interactions -- 3.5 Magnetic hyperfine interactions -- 3.6 Combined magnetic and quadrupole interactions -- 3.7 Relative intensities of absorption lines -- 3.8 Relaxation phenomena -- 3.9 Anisotropy of the recoilless fraction -- 3.10 The pseudoquadrupole interaction -- 4. Applications of the Mössbauer Effect -- 4.1 Relativity and …