DOI: 10.17188/1204160
title: Materials Data on Ta2Bi4O11 by Materials Project

description: Bi4Ta2O11 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with three equivalent TaO6 octahedra, a cornercorner with one BiO7 pentagonal bipyramid, a cornercorner with one BiO6 pentagonal pyramid, an edgeedge with one BiO7 pentagonal bipyramid, and an edgeedge with one BiO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 14–31°. There are a spread of Ta–O bond distances ranging from 1.93–2.11 Å. In the second Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with three equivalent TaO6 octahedra, a cornercorner with one BiO7 pentagonal bipyramid, a cornercorner with one BiO6 pentagonal pyramid, and an edgeedge with one BiO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 14–31°. There are a spread of Ta–O bond distances ranging from 1.94–2.11 Å. There are four inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded to seven O2- atoms to form distorted BiO7 pentagonal bipyramids that share corners with two TaO6 octahedra, a cornercorner with one BiO6 pentagonal pyramid, an edgeedge with one TaO6 octahedra, edges with two equivalent BiO7 pentagonal bipyramids, and an edgeedge with one BiO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 53–57°. There are a spread of Bi–O bond distances ranging from 2.35–2.69 Å. In the second Bi3+ site, Bi3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Bi–O bond distances ranging from 2.33–2.58 Å. In the third Bi3+ site, Bi3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Bi–O bond distances ranging from 2.11–2.69 Å. In the fourth Bi3+ site, Bi3+ is bonded to six O2- atoms to form distorted BiO6 pentagonal pyramids that share corners with two TaO6 octahedra, a cornercorner with one BiO7 pentagonal bipyramid, edges with two TaO6 octahedra, and an edgeedge with one BiO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 34–37°. There are a spread of Bi–O bond distances ranging from 2.13–2.72 Å. There are eleven inequivalent O2- sites. In the first O2- site, O2- is bonded to four Bi3+ atoms to form distorted OBi4 tetrahedra that share corners with six OTaBi3 tetrahedra and edges with two OBi4 tetrahedra. In the second O2- site, O2- is bonded in a 4-coordinate geometry to one Ta5+ and three Bi3+ atoms. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one Ta5+ and two Bi3+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Ta5+ and two Bi3+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to one Ta5+ and three Bi3+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Ta5+ and three Bi3+ atoms. In the seventh O2- site, O2- is bonded to one Ta5+ and three Bi3+ atoms to form a mixture of distorted edge and corner-sharing OTaBi3 tetrahedra. In the eighth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Ta5+ and one Bi3+ atom. In the ninth O2- site, O2- is bonded in a linear geometry to two Ta5+ atoms. In the tenth O2- site, O2- is bonded to four Bi3+ atoms to form a mixture of distorted edge and corner-sharing OBi4 tetrahedra. In the eleventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Ta5+ and one Bi3+ atom.