Neutron diffraction provides similar structural information as electron diffraction. Neutron beams interact more strongly with nuclei than do x-rays and neutron diffraction is more useful than x-ray diffraction for determining proton positions. Neutrons interact with a solid to a much lesser degree than x-rays and therefore have advantages in studying materials that are damaged by x-rays and in cases where a large penetration depth is desired. For the three types of diffraction methods, neutrons are unique in that they have a magnetic moment and are therefore sensitive to magnetic ordering in a solid.
Neutrons are produced by nuclear reactions in either a nuclear reactor or in an accelerator. Reactor sources produce a continuous spectrum of neutron energies and require a monochromator crystal to select a particular energy. Accelerator sources are usually operated in a pulsed mode and neutron wavelength is selected by time-of-flight methods, that is, data is taken at a fixed Bragg angle as a function of neutron energy.
/chem-ed/diffract/neutron.htm, updated 10/14/96
Copyright © 1996 by Brian M. Tissue, all rights reserved.
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