Materials Data on Sr6Ta2O11 by Materials Project

Abstract

Sr6Ta2O11 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. there are three inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.64–3.10 Å. In the second Sr2+ site, Sr2+ is bonded to five O2- atoms to form distorted SrO5 square pyramids that share corners with four equivalent TaO6 octahedra and a cornercorner with one TaO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 10°. There are four shorter (2.30 Å) and one longer (2.85 Å) Sr–O bond lengths. In the third Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are two shorter (2.32 Å) and four longer (2.57 Å) Sr–O bond lengths. There are two inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to five O2- atoms to form distorted TaO5 trigonal bipyramids that share a cornercorner with one SrO5 square pyramid. There is one shorter (1.91 Å) and four longer (1.97 Å) Ta–O bond length. In the second Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with four equivalent SrO5 square pyramids. There is two shorter (1.95 Å) and four longer (2.01 Å) Ta–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to five Sr2+ and one Ta5+ atom. In the second O2- site, O2- is bonded in a distorted linear geometry to five Sr2+ and one Ta5+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one Ta5+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to five Sr2+ and one Ta5+ atom.