论文信息 - X-ray reflectivities, at low and high order of reflection, of flat highly oriented pyrolytic graphite crystals

X-ray reflectivities, at low and high order of reflection, of flat highly oriented pyrolytic graphite crystals

Abstract Integrated reflectivities of flat highly oriented pyrolytic graphite crystals have been measured at various energies (5.9 ≤E ≤ 15.10 keV) and for various orders of reflection n (1 ≤n ≤ 5). For low n values, the reflectivity is severely affected by secondary extinction; our results show that the theory of Zachariasen represents the experiment reasonably well, a conclusion reached by other authors for the case of n = 1 reflections. For high n values, the reflectivity is more sensitive to the structure factor's temperature correction, a quantity not precisely known. Our measurements are in favour of the larger temperature correction within the range reported in the literature.

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