Abstract: The small-angle X-ray scattering (SAXS) is a nondestructive method for the analysis of nanostructures in a wide variety of materials. This method allows determining averaged structural parameters on a length scale from just above atomic size up to several 100 nanometers, such as size distributions, volume fractions, and inner surface sizes. Moreover, anomalous small-angle X-ray scattering (ASAXS) exploits the anomalous dispersion of the scattering amplitudes near the X-ray absorption edges of elements contained in the sample. These element-sensitive contrast variations are used to analyze averaged composition fluctuations on the nanometer scale.
This talk will elaborate on the advantages of ASAXS in the analysis of complex materials. First, some technical details of the ASAXS dedicated instrument at the BESSY II synchrotron will be presented. The instrument is moveable, can be attached to different monochromatic X-ray sources, and is optimized for ASAXS as well as grazing incidence SAXS. Construction details and strategies necessary for ASAXS will be emphasized. Nowadays, it is used in an energy range of 2-10 keV.