Prokes, Karel; Yokaichiya, Fabiano: Elastic Neutron Diffraction on Magnetic Materials. In: Brück, Ekkes [Ed.] : Handbook of Magnetic Materials / Volume 25. Amsterdam: Elsevier, 2016. - ISBN 978-0-444-63871-7, p. 67-144

The neutron as an elementary particle has been discovered in 1932 by Chadwick and soon it was recognized as being useful for studies of magnetic materials (Bloch, 1936). Since the first successful experiments in the mid of last century by Shull and Brockhouse, it has been used for studying various materials (both were awarded in 1994 with the Nobel Prize for Physics, for the development of different neutron techniques). Today, neutron scattering and diffraction are among the most widely used microscopic tools in condensed matter research, especially in the field of magnetism, phase transitions, and elementary collective excitations. It was the technique of choice to prove the existence of an antiferromagnetic state predicted by Ne`el, another Nobel Prize laureate (1970). An experiment on MnO has disclosed additional Bragg reflections at temperatures below the magnetic phase transition proving the appearance of a new periodicity in this material (Shull and Smart, 1949). Since then, neutron sciences have contributed enormously to the knowledge of human beings in many different fields and continue to do so till present (Brammer, 2003; Bru¨ck, 2005; Catalan and Scott, 2009; Tokura, 2006; Zaccai, 2000). A vast variety of different techniques have been developed and it is simply impossible to mention them all at this place in detail. For more detailed information, we advise the reader to consult several very excellent books (Bacon, 1975; Furrer et al., 2008; Izyumov and Ozerov, 1970; Marshal and Lovesey, 1971; Squires, 1978). In this chapter we give merely a dense overview of the elastic neutron diffraction technique as tool for studying magnetic materials, along with several representative examples documenting the main notions of this technique. The chapter is meant to help the reader to understand the variety of advantages and also limitations of the method. By no means is it supposed to duplicate many useful textbooks and texts already existing.