Determination of the largest particle dimension by direct Fourier cosine transformation of experimental small-angle X-ray scattering data

The largest dimension, L, of a scattering particle is an essential structure parameter of the sample and is necessary both for designing and carrying out experiments and also for analysis of the scattering data. It is shown that L, which is identical to the upper-limit frequency of the scattering curve, can always be evaluated from a Fourier cosine transformation of scattering data which are not corrected for collimation effects, regardless of the shape of the primary beam.