The structural studies of powder diffraction using synchrotron radiation X-ray data have been described with some examples. The C2entrapping structure of yttrium di-metallofullerene has been determined by Maximum Entropy method (MEM) combined with Rietveld refinement. The MEM analysis of Zn4Sb3, which is one of the most efficient thermoelectric materials, has been presented by both powder and single crystal method. The structure determination of a single-component palladium complex with extended TTF-type dithiolate ligands has also been described.