The content of this volume has been added to eMagRes (formerly Encyclopedia of Magnetic Resonance) – the ultimate online resource for NMR and MRI. Over the past 20 years technical developments in superconducting magnet technology and instrumentation have increased the potential of NMR spectroscopy so that it is now possible to study a wide range of solid materials. In addition, one can probe the nuclear environments of many other additional atoms that possess the property of spin. In particular,...