Ceramics include inorganic materials that are not metals or alloys and they are synthesized by heating at high temperature. Ceramic materials have a variety of different structures. The basic structural data that we need to determine if we want to describe the structure of a crystal are the unit cell parameters, the type and coordinates of the atoms in the asymmetric unit, and the space group. The displacement parameters of the atoms may be determined and sometimes also their positions occupancy. Structural models can also be used to determine the structure of the product. As part of this work, we performed approximate structural characterization of gallium- strontium titanate (IV), with the application of the preliminary measurements, based on the the years ago prepared product. Qualitative X-ray powder analysis, based on the measured powder diffractogram, was performed with the computer program Crystallographica Search Match-CSM. Using the ICSD-Desktop program, we searched through the ICSD crystal structure database for the structural data of the reactants used in the product synthesis and for aluminum-strontium titanate (IV), which served as a structural model. Using the TOPAS 2.1 program, we performed the Rietveld-refinement, which was used to calculate the mass fraction of the crystalline phases in the crystalline part of the sample and to determine the approximate crystal structure of gallium-strontium titanate (IV), drawn with the Mercury program. As part of this work, we confirmed that the structure of aluminum-strontium titanate (IV) is a suitable structural model for determining the crystal structure of gallium-strontium titanate (IV). The structure of the product, like the structural model, shows a monoclinic space group C2 / c and a very similar, however slightly larger unit cell, which is consistent with the slightly larger gallium(III) ionic radius than for aluminum(III).
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