Syntheses and structure of hydrothermally prepared CsNiX3 (X=Cl, Br, I)

During reinvestigation of the hydrothermal synthesis reported earlier of the compound cesium nickel phosphide, “CsNiP”, we arrived at a new route to the synthesis of the cesium nickel halide compounds CsNiX3 (X=Cl, Br, I). The method has also been shown to extend to cobalt and iron compounds. Single crystals of these compounds were synthesized in phosphoric acid in sealed autoclaves. Their structures were determined by single-crystal X-ray diffraction methods. The compounds crystallize in the hexagonal space group P63/mmc in the BaNiO3 structure type. The synthetic method and the resultant crystallographic details for CsNiCl3 are essentially identical with those reported earlier for the synthesis and structure of “CsNiP”.

Graphical abstractThe CsNiX3 (X=Cl, Br, I) structure. Cesium is blue, nickel is in dark green polyhedra, halide is brown.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► A hydrothermal approach to single crystal growth of cesium transition-metal halides. ► Reexamination of “CsNiP” to determine its composition as CsNiCl3. ► X-ray single-crystal structures of CsNiBr3 and CsNiI3.