Abstract: According to the small-angle X-ray scattering theory, it is always assumed that the scattering intensities of particles are simply added up to give the total diffraction pattern. This is true only for a very dilute particle system. However, with increasing concentration, some effects of interpartiole interference should be expected. Several models and theories of interpartiole interference have been presented but no rigorous solution can be given so far. In the practical case, the magnitude of the concentration effects can be seen by plotting the scattering curves of the various concentrated particle systems, normalized to unit concentration. Sometimes it is impossible to measure a series of concentrations in the applications of materials science, such as determining the size distribution of a mioro-inhomogeneous region, global droplets of spinodal decomposition, precipitation of the second phase, condensation of vacancies and defects in bulk materials. Therefore, it is of importance to find an empii-ical equation of the interference function. The intensities of ultrafine MoSs samples in several concentrations at different angles are determined in detail. The empirical equation of the interference Junction is deduced as:K^-1=[1+2.5ω^1.4+2θ° (15.4ω^0.5-23.6ω²-1.3ω^0.01)]^-1.

Key words: small-angle X-ray scattering, effects of interpartiole interference