Contents

Chapter 1. Introduction
1

Chapter 2. The Origin of Atomic Moments
3

2.1. Spin and Orbital States of Electrons
3

2.2. The Vector Model of Atoms
5

Chapter 3. Paramagnetism of Free Ions
11

3.1. The Brillouin Function
11

3.2. The Curie Law
13

References
17

Chapter 4. The Magnetically Ordered State
19

4.1. The Heisenberg Exchange Interaction and the Weiss Field
19

4.2. Ferromagnetism
22

4.3. Antiferromagnetism
26

4.4. Ferrimagnetism
34

References
41

Chapter 5. Crystal Fields
43

5.1. Introduction
43

5.2. Quantum-Mechanical Treatment
44

5.3. Experimental Determination of Crystal-Field Parameters
50

5.4. The Point-Charge Approximation and Its Limitations
52

5.5. Crystal-Field-Induced Anisotropy
54

5.6. A Simplified View of 4f-Electron Anisotropy
56

References
57

Chapter 6. Diamagnetism
59

Reference
61

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