Materials Data on Ba2Nb8O11 by Materials Project
Ba2Nb8O11 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ba2+ is bonded in a distorted q6 geometry to ten O2- atoms. There are eight shorter (2.91 Å) and two longer (3.00 Å) Ba–O bond lengths. There are three inequivalent Nb+2.25+ sites. In the first Nb+2.25+ site, Nb+2.25+ is bonded in a square co-planar geometry to four O2- atoms. There are two shorter (2.12 Å) and two longer (2.13 Å) Nb–O bond lengths. In the second Nb+2.25+ site, Nb+2.25+ is bonded in a rectangular see-saw-like geometry to four equivalent O2- atoms. All Nb–O bond lengths are 2.12 Å. In the third Nb+2.25+ site, Nb+2.25+ is bonded to five O2- atoms to form corner-sharing NbO5 square pyramids. There are one shorter (2.09 Å) and four longer (2.13 Å) Nb–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+ and two equivalent Nb+2.25+ atoms. In the second O2- site, O2- is bonded to two equivalent Ba2+ and three Nb+2.25+ atoms to form a mixture of distorted corner and edge-sharing OBa2Nb3 trigonal bipyramids. In the third O2- site, O2- is bonded in a square co-planar geometry to four equivalent Nb+2.25+ atoms.