A complex Ce bearing oxide, Gd2Ce2O7 was synthesized in order to simulate Pu in a fluorite derivative oxide. X-ray diffraction (XRD) was collected using a lab diffractometer at room temperature and Rietveld refinements of the XRD pattern was carried out using GSAS and XND programs. The diffraction pattern could be indexed with a C-type cubic bixbyite crystal structure with a cell parameter of 10.86413(8) Å. Several peaks showed peak asymmetry and line broadening and could not be fitted with conventional Rietveld refinement procedures. A full pattern refinement, assuming a possible formation of micro domains of a disordered phase with short range ordering and a structure correlated with the host C-type cubic lattice, gave a good fit with the experimental data. Understanding the structure of host lattice and its relation with the micro domains can have a profound effect on the radiation stability of this material. The diffraction data analysis and computational results will be presented and correlated with the complementary data obtained from transmission electron microscopy and Raman spectroscopy analysis.