Materials Data on Ta8Pb6O25 by Materials Project
Ta8Pb6O25 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eight inequivalent Ta+4.75+ sites. In the first Ta+4.75+ site, Ta+4.75+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and edges with four PbO7 hexagonal pyramids. The corner-sharing octahedra tilt angles range from 36–43°. There are a spread of Ta–O bond distances ranging from 1.96–2.04 Å. In the second Ta+4.75+ site, Ta+4.75+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and edges with two PbO7 hexagonal pyramids. The corner-sharing octahedra tilt angles range from 37–44°. There are a spread of Ta–O bond distances ranging from 1.94–2.05 Å. In the third Ta+4.75+ site, Ta+4.75+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and edges with four PbO7 hexagonal pyramids. The corner-sharing octahedra tilt angles range from 36–43°. There are a spread of Ta–O bond distances ranging from 1.96–2.04 Å. In the fourth Ta+4.75+ site, Ta+4.75+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and edges with two PbO7 hexagonal pyramids. The corner-sharing octahedra tilt angles range from 34–44°. There are a spread of Ta–O bond distances ranging from 1.94–2.06 Å. In the fifth Ta+4.75+ site, Ta+4.75+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and edges with four PbO7 hexagonal pyramids. The corner-sharing octahedra tilt angles range from 36–42°. There are a spread of Ta–O bond distances ranging from 1.96–2.04 Å. In the sixth Ta+4.75+ site, Ta+4.75+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and edges with four PbO7 hexagonal pyramids. The corner-sharing octahedra tilt angles range from 36–42°. There are a spread of Ta–O bond distances ranging from 1.98–2.02 Å. In the seventh Ta+4.75+ site, Ta+4.75+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and edges with two PbO7 hexagonal pyramids. The corner-sharing octahedra tilt angles range from 37–44°. There are a spread of Ta–O bond distances ranging from 1.96–2.04 Å. In the eighth Ta+4.75+ site, Ta+4.75+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and edges with two PbO7 hexagonal pyramids. The corner-sharing octahedra tilt angles range from 34–44°. There are a spread of Ta–O bond distances ranging from 1.94–2.05 Å. There are six inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded in a hexagonal planar geometry to six O2- atoms. There are a spread of Pb–O bond distances ranging from 2.65–2.89 Å. In the second Pb2+ site, Pb2+ is bonded in a hexagonal planar geometry to six O2- atoms. There are a spread of Pb–O bond distances ranging from 2.68–2.85 Å. In the third Pb2+ site, Pb2+ is bonded to seven O2- atoms to form distorted PbO7 hexagonal pyramids that share a cornercorner with one PbO7 hexagonal pyramid, edges with three PbO7 hexagonal pyramids, and edges with six TaO6 octahedra. There are a spread of Pb–O bond distances ranging from 2.37–2.77 Å. In the fourth Pb2+ site, Pb2+ is bonded to seven O2- atoms to form distorted PbO7 hexagonal pyramids that share a cornercorner with one PbO7 hexagonal pyramid, edges with three PbO7 hexagonal pyramids, and edges with six TaO6 octahedra. There are a spread of Pb–O bond distances ranging from 2.36–2.74 Å. In the fifth Pb2+ site, Pb2+ is bonded to seven O2- atoms to form distorted PbO7 hexagonal pyramids that share a cornercorner with one PbO7 hexagonal pyramid, edges with three PbO7 hexagonal pyramids, and edges with six TaO6 octahedra. There are a spread of Pb–O bond distances ranging from 2.37–2.79 Å. In the sixth Pb2+ site, Pb2+ is bonded to seven O2- atoms to form distorted PbO7 hexagonal pyramids that share a cornercorner with one PbO7 hexagonal pyramid, edges with three PbO7 hexagonal pyramids, and edges with six TaO6 octahedra. There are a spread of Pb–O bond distances ranging from 2.37–2.78 Å. There are twenty-five inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Ta+4.75+ and one Pb2+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Ta+4.75+ and one Pb2+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Ta+4.75+ and one Pb2+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two Ta+4.75+ and two Pb2+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to two Ta+4.75+ and two Pb2+ atoms. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Ta+4.75+ and two Pb2+ atoms. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Ta+4.75+ and two Pb2+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two Ta+4.75+ and two Pb2+ atoms. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to two Ta+4.75+ and two Pb2+ atoms. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to two Ta+4.75+ and two Pb2+ atoms. In the eleventh O2- site, O2- is bonded in a tetrahedral geometry to four Pb2+ atoms. In the twelfth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Ta+4.75+ and two Pb2+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Ta+4.75+ and one Pb2+ atom. In the fourteenth O2- site, O2- is bonded in a bent 150 degrees geometry to two Ta+4.75+ atoms. In the fifteenth O2- site, O2- is bonded in a 2-coordinate geometry to two Ta+4.75+ and two Pb2+ atoms. In the sixteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Ta+4.75+ and one Pb2+ atom. In the seventeenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Ta+4.75+ and two Pb2+ atoms. In the eighteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Ta+4.75+ and one Pb2+ atom. In the nineteenth O2- site, O2- is bonded in a 2-coordinate geometry to two Ta+4.75+ and two Pb2+ atoms. In the twentieth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Ta+4.75+ and two Pb2+ atoms. In the twenty-first O2- site, O2- is bonded in a 2-coordinate geometry to two Ta+4.75+ and two Pb2+ atoms. In the twenty-second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Ta+4.75+ and one Pb2+ atom. In the twenty-third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Ta+4.75+ and one Pb2+ atom. In the twenty-fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Ta+4.75+ and one Pb2+ atom. In the twenty-fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Ta+4.75+ and one Pb2+ atom.