Materials Data on Na2SrAl4(B2O7)2 by Materials Project

Abstract

Na2SrAl4(B2O7)2 crystallizes in the trigonal P3 space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.42 Å) and three longer (2.94 Å) Na–O bond lengths. In the second Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.31 Å) and three longer (2.85 Å) Na–O bond lengths. Sr2+ is bonded to six O2- atoms to form SrO6 octahedra that share corners with six AlO4 tetrahedra. There are three shorter (2.52 Å) and three longer (2.65 Å) Sr–O bond lengths. There are four inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with three equivalent SrO6 octahedra and a cornercorner with one AlO4 tetrahedra. The corner-sharing octahedral tilt angles are 66°. There is one shorter (1.67 Å) and three longer (1.80 Å) Al–O bond length. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There is one shorter (1.75 Å) and three longer (1.77 Å) Al–O bond length. In the third Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with three equivalent SrO6 octahedra and a cornercorner with one AlO4 tetrahedra. The corner-sharing octahedral tilt angles are 65°. There is one shorter (1.71 Å) and three longer (1.79 Å) Al–O bond length. In the fourth Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There is one shorter (1.73 Å) and three longer (1.77 Å) Al–O bond length. There are four inequivalent B3+ sites. In the first B3+ site, B3+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All B–O bond lengths are 1.39 Å. In the second B3+ site, B3+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All B–O bond lengths are 1.38 Å. In the third B3+ site, B3+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All B–O bond lengths are 1.38 Å. In the fourth B3+ site, B3+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All B–O bond lengths are 1.39 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to three equivalent Na1+ and two Al3+ atoms. In the second O2- site, O2- is bonded in a linear geometry to two Al3+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+, one Al3+, and one B3+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Sr2+, one Al3+, and one B3+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Al3+, and one B3+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Sr2+, one Al3+, and one B3+ atom.