Ionothermal synthesis of the mixed-anion material, Ba3Cl4CO3

A low-temperature ionothermal method for the facile synthesis of the halide carbonate, Ba3Cl4CO3, in single-crystalline form has been developed. This has enabled the first determination of the crystal structure of this material to be carried out. Analysis of single-crystal X-ray diffraction data indicates that barium chloride carbonate crystallises in the orthorhombic space group Pnma (Z=4), with a=8.4074(11), b=9.5886(12), c=12.4833(15) A (Rw=0.0392). It exhibits a complex structure in which a three-dimensional network is formed from cross-linking of chains of anion-centred octahedra that share faces. - Graphical Abstract: Ionothermal synthesis has provided single crystals of the mixed-anion material barium chloride carbonate, enabling the first determination of the complex crystal structure of this phase to be performed.