STRUCTURAL-ANALYSIS OF CHEMICAL AND TOPOLOGICAL INHOMOGENEITIES BY ASAXS

From ASAXS measurements partial pair correlations can be determined both in the fluctuations DELTAc(i)(r underbar) = c(i)(r underbar) - c(i)BAR of the local concentrations c(i)(r underbar) = n(i)(r underbar)/n(r underbar) of the i(th) species and in the fluctuations DELTAn(r underbar) = n(r underbar) - nBAR of the local number density of all kinds of atoms. This requires a separation of the measured intensity into partial intensities which depend linearly on the squared average atomic form factor, form factor differences and cross terms. The structural analysis is illustrated for the example of simple 2-phase models.