High-Pressure Structures and Superconductivity of Barium Iodide

Generally, pressure is a useful tool to modify the behavior of physical properties of materials due to the change in distance between atoms or molecules in the lattice. Barium iodide (BaI2), as one of the simplest and most prototypical iodine compounds, has substantial high pressure investigation value. In this work, we explored the crystal structures of BaI2 at a wide pressure range of 0–200 GPa using a global structure search methodology. A thermodynamical structure with tetragonal I4/mmm symmetry of BaI2 was predicted to be stable at 17.1 GPa. Further electronic calculations indicated that I4/mmm BaI2 exhibits the metallic feature via an indirect band gap closure under moderate pressure. We also found that the superconductivity of BaI2 at 30 GPa is much lower than that of CsI at 180 GPa based on our electron–phonon coupling simulations. Our current simulations provide a step toward the further understanding of the high-pressure behavior of iodine compounds at extreme conditions.

Study of Barium Iodide-Hexamethylentetramin-Water System

Research relevance in this article is based on study of heterogeneous equilibria in ternary aqueous systems BaI2 — (CH2)6N4 — H2O, as synthesized complexes can be used as an antibacterial drug in veterinary medicine. Materials and research methods: heterogeneous equilibria were studied by the isothermal solubility method at 25 °С. Concentration limits of compounds existence and their solubility types have been established. Research objectives: to determine chemical bond types between the complexing agent and the ligand, as well as the general laws of thermal decomposition of synthesized compounds. Research results: the solubility isotherm of the BaI2 — (CH2)6N4 — H2O system has been studied and compiled. Conclusions: effect of anions on complexation and composition of resulting compounds were revealed.

Preparation and study of the luminescent glass-ceramics based on barium iodide activated with Eu2+

In this paper an original method for obtaining glass-ceramics based on barium iodide powder activated with Eu2+ is proposed, their structural and spectral-luminescent properties are investigated. X-ray diffraction analysis has evidenced that glass-ceramics containing BaI2 ∙ 2H2O and BaI2 are formed when 50 mas. % of the starting iodide powder is used in the synthesis process. The possibility of using glass-ceramics for preventing the contact of iodide powder with water vapor has been confirmed.