Materials Data on NaSr2Ta3O9 by Materials Project

Abstract

NaSr2Ta3O9 is (Cubic) Perovskite-derived structured and crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with six equivalent NaO12 cuboctahedra, corners with six equivalent SrO12 cuboctahedra, faces with six equivalent SrO12 cuboctahedra, and faces with eight TaO6 octahedra. There are six shorter (2.86 Å) and six longer (2.88 Å) Na–O bond lengths. Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with three equivalent NaO12 cuboctahedra, corners with nine equivalent SrO12 cuboctahedra, faces with three equivalent NaO12 cuboctahedra, faces with three equivalent SrO12 cuboctahedra, and faces with eight TaO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.83–2.86 Å. There are two inequivalent Ta+4.33+ sites. In the first Ta+4.33+ site, Ta+4.33+ is bonded to six equivalent O2- atoms to form TaO6 octahedra that share corners with six equivalent TaO6 octahedra, faces with two equivalent NaO12 cuboctahedra, and faces with six equivalent SrO12 cuboctahedra. The corner-sharing octahedral tilt angles are 2°. All Ta–O bond lengths are 2.02 Å. In the second Ta+4.33+ site, Ta+4.33+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra, faces with three equivalent NaO12 cuboctahedra, and faces with five equivalent SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are three shorter (2.01 Å) and three longer (2.03 Å) Ta–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to one Na1+, three equivalent Sr2+, and two Ta+4.33+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to two equivalent Na1+, two equivalent Sr2+, and two equivalent Ta+4.33+ atoms.