Grazing incidence scattering

Figure 1.7 sketches the grazing incidence scattering geometry used for studies of thin films and surfaces. The set of polarization vectors (cr, n), the polar and azimuthal angles (0, ) describing the relative orientation of the v/ave vector ko of the incident photons to the direction of the magnetization vector m of the sample are indicated. 

Grazing incidence scattering geometry the photon beam with a wave vector k is illuminating the sample at an incidence angle (typically below 1 ).The polarization vector basis of the phonon (ejJ = x,y,z) and the projections of and 6y along the direction of the beam propagation are shown, n denotes the surface normal. 

Gutmann JS, Miiller-Buschbaum P, WoDcenhauer M, Hermsdorf N, Stamm M. X-ray and neutron grazing incidence scattering study of a ternary ultra-thin polymer blend film. J Macromol Sci B 2005 43 207-217. 

HEED High-energy electron diffraction [104] Diffraction of elastically back-scattered electrons (-20 keV, grazing incidence) Surface structure... 

Melroy O R, Toney M F, Borges G L, Samant M G, Kortright J B, Ross P N and Blum L 1989 An In situ grazing incidence x-ray scattering study of the initial stages of electrochemical growth of lead on silver(111) J. Electroanal. Chem. 258 403-14... 

FIGURE 27.7 Grazing incidence X-ray scattering geometry. The X-rays are incident on the sample at an angle (j) and are detected at a combination of two angles 29 and 2c ). ... 

Special care has to be taken concerning data pre-evaluation if the scattering of highly oriented nanostructures are investigated in symmetrical reflection or at grazing incidence. Absorption correction is delicate (cf. Sect. 7.6.3). Even a refraction correction (Sect. 7.6.5) may be necessary118. 

However, at grazing incidence angles near the critical angle the reflected beam becomes important, and eventually becomes dominant. This is an important effect and the two-beam case is seriously in error for angles of incidence close to the critical angle. Fortunately, the reflected beam decreases in intensity as the fourth power of the scattering angle, and is weak compared with the diffracted... 

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