Interactive Experimentation and Modeling for Phase Equilibrium

The thermodynamic descriptions of the perovskite phase SrZrO3 and the TbBr3-KBr molten salt system were carried out using the available experimental information. Special attention was paid to the structural behavior of SrZrO3 and the decomposition of K3TbBr6 at low temperature, respectively, to illustrate how to select an appropriate thermodynamic model based on crystal structure and chemistry information, how to identify and resolve the inconsistency between various kinds of experimental data, and how to use thermodynamic modeling as a basic tool in the development and optimization of materials and process. In the present work, different structures of SrZrO3 were explained by thermodynamic calculation and confirmed with experimental technologies. The decomposition of the compound K3TbBr6 at about 593 K was detected by the present thermodynamic calculation and the new complementary experimental measurements. Comparison between the calculated and measured phase diagrams as well as thermodynamic quantities provided the final test of the overall consistency between the reliable experimental information and the present modeling and thermodynamic computation.

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