Bragg-scattering

Bragg scattering Coherent elastic scattering of monochromatic neutrons by a set of crystal planes. 

For local deviations from random atomic distribution electrical resistivity is affected just by the diffuse scattering of conduction electrons LRO in addition will contribute to resistivity by superlattice Bragg scattering, thus changing the effective number of conduction electrons. When measuring resistivity at a low and constant temperature no phonon scattering need be considered ar a rather simple formula results ... 

The Bragg scattering of X-rays by a periodic lattice in contrast to a Mossbauer transition is a collective event which is short in time as compared to the typical lattice vibration frequencies. Therefore, the mean-square displacement (x ) in the Debye-Waller factor is obtained from the average over the ensemble, whereas (r4) in the Lamb-Mossbauer factor describes a time average. The results are equivalent. 

Another technique widely used to measure the cholesteric pitch is based on the Bragg scattering of monochromatic light (obtained by a helium-neon laser) from fingerprint or planar textures of the cholesteric32 Its angular dependence is strictly related to the cholesteric pitch. 

Note 3 Chiral nematic mesophases exhibit Bragg scattering of circularly polarised light at a wavelength proportional to the pitch P (Xr = P, where is the mean refractive index). 

The wave function P contains all information of the joint probability distribution of the electrons. For example, the two-electron density is obtained from the wave function by integration over the spin and space coordinates of all but two electrons. It describes the joint probability of finding electron 1 at r, and electron 2 at r2. The two-electron density cannot be obtained from elastic Bragg scattering. 

Kubayashi, K., Kawata, H., and Mori, K. (1998). Site specification on normal and magnetic XANES of ferrimagnetic Fc304 by means of resonant magnetic Bragg scattering. J. Synch. Rad. 5, 972-4. 

Fig. 7. Illustration of magnetic Bragg scatterings in 1-D, 2-D or 3-D magnetic orderings...

Figure 7 illustrates magnetic Bragg scatterings of low-dimensional systems33. Since in a 3-D material, Bragg peaks are observed, in a 2-D system lines, and in a 1-D material planes will be detected. 

Finally, X rays of a certain X can specifically excite X-ray luminescence of the sample. Thus, Cu-Ka line will excite iron atoms, and Mo-K those of yttrium, producing a strong parasitic background which (imlike Bragg scattering) does not decrease with the increase of the Bragg angle - a most unwelcome complication. 

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