Real-space distributions from small-angle scattering data: Structure interference method versus indirect transformation method

The indirect transformation method (program ITP) developed by Glatter since 1977 is still one of the most popular methods for obtaining real-space information from small-angle scattering data. In order to validate the novel structure interference method (SIM), a comparison of the two methods has been performed with both simulated and experimental data. Although no explicit smoothing criterion is used in SIM, the solutions are less influenced by oscillations, termination effects are smaller and higher real-space resolution is obtained compared with ITP. It has been found that the structure interference method is very robust even in the case of incomplete data (h(1) R(max) > pi) where the indirect transformation method fails to find a physically meaningful solution.