Materials Data on Na3BiBAsO7 by Materials Project
Na3BBiAsO7 crystallizes in the monoclinic P2_1/m 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 a spread of Na–O bond distances ranging from 2.42–2.86 Å. In the second Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.26–2.64 Å. B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.34 Å) and two longer (1.42 Å) B–O bond length. Bi3+ is bonded to six O2- atoms to form distorted BiO6 octahedra that share corners with four equivalent AsO4 tetrahedra. There are a spread of Bi–O bond distances ranging from 2.25–2.64 Å. As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with four equivalent BiO6 octahedra. The corner-sharing octahedra tilt angles range from 49–71°. There is one shorter (1.71 Å) and three longer (1.74 Å) As–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to four Na1+ and one B3+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one B3+, and one Bi3+ atom. In the third O2- site, O2- is bonded to three Na1+, one B3+, and one Bi3+ atom to form distorted corner-sharing ONa3BiB trigonal bipyramids. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Bi3+, and one As5+ atom. In the fifth O2- site, O2- is bonded to two equivalent Na1+, one Bi3+, and one As5+ atom to form distorted corner-sharing ONa2BiAs tetrahedra. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+, one Bi3+, and one As5+ atom.