International
Tables for Crystallography Volume H Powder diffraction Edited by C. J. Gilmore, J. A. Kaduk and H. Schenk © International Union of Crystallography 2018 
International Tables for Crystallography (2018). Vol. H, ch. 2.2, p. 58
Figure 2.2.11^{a} 

Figure 2.2.11
Δ(2θ) calculated from equation (2.2.2) for a beamline with a doublecrystal Si(111) monochromator, an Si(111) analyser (Δ_{m} = Δ_{a} and θ_{m} = θ_{a}) and an FWHM vertical divergence of 25 µrad at λ = 0.4 Å (solid line: Δ_{m} ≃ 8.3 µrad, θ_{m} = 3.6571°), λ = 0.8 Å (dashed line: Δ_{m} ≃ 16.6 µrad, θ_{m} = 7.3292°) and λ = 1.2 Å (dotted line: Δ_{m} ≃ 25.2 µrad, θ_{m} = 11.0319°). 