Materials Data on Ba2NiF6 by Materials Project
Ba2NiF6 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ba2+ is bonded in a 12-coordinate geometry to twelve F1- atoms. There are a spread of Ba–F bond distances ranging from 2.63–3.24 Å. Ni2+ is bonded to six F1- atoms to form corner-sharing NiF6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (1.96 Å) and four longer (2.07 Å) Ni–F bond lengths. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted single-bond geometry to four equivalent Ba2+ and one Ni2+ atom. In the second F1- site, F1- is bonded in a linear geometry to four equivalent Ba2+ and two equivalent Ni2+ atoms. In the third F1- site, F1- is bonded to four equivalent Ba2+ atoms to form a mixture of edge and corner-sharing FBa4 tetrahedra.