Rerefinement of the crystal structure of BiF₅

The crystal structure of bismuth pentafluoride, BiF 5 , was rerefined from single-crystal data. BiF 5 crystallizes in the α-UF 5 structure type in the form of colorless needles. In comparison with the previously reported crystal-structure model [Hebecker (1971). Z. Anorg. Allg. Chem. 384 , 111–114], the lattice parameters and fractional atomic coordinates were determined to much higher precision and all atoms were refined anisotropically, leading to a significantly improved structure model. The Bi atom (site symmetry 4/ m ..) is surrounded by six F atoms in a distorted octahedral coordination environment. The [BiF 6 ] octahedra are corner-linked to form infinite straight chains extending parallel to [001]. Density functional theory (DFT) calculations at the PBE0/TZVP level of theory were performed on the crystal structure of BiF 5 to calculate its IR and Raman spectra. These are compared with experimental data.