Examination of Errors in the Determination of Phase Boundary Thickness by Small Angle X-ray Scattering

摘要

The method of determining the thickness of diffuse phase boundary with density profile governed by equilibrium conditions is proposed. It follows the well-known procedure of analyzing the deviations from Porod's law. Errors in the obtained boundary thickness, due to statistical scatter in the intensity data and to the difficulty of separating the effect of density fluctuations within the phases, are examined. For this purpose, scattering curves are synthesized on the basis of a well-defined model structure with known boundary thicknesses. These synthesized curves, when analyzed according to the proposed method, yield the correct boundary thickness under favorable conditions, but are also shown to lead to very erroneous results in some cases. (Author)