Materials Data on LaNb3O9 by Materials Project
LaNb3O9 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent La3+ sites. In the first La3+ site, La3+ is bonded to twelve O2- atoms to form LaO12 cuboctahedra that share corners with three LaO12 cuboctahedra, faces with two equivalent LaO12 cuboctahedra, and faces with eight NbO6 octahedra. There are a spread of La–O bond distances ranging from 2.60–2.88 Å. In the second La3+ site, La3+ is bonded to twelve O2- atoms to form LaO12 cuboctahedra that share corners with three LaO12 cuboctahedra, faces with two equivalent LaO12 cuboctahedra, and faces with eight NbO6 octahedra. There are a spread of La–O bond distances ranging from 2.64–2.87 Å. There are six inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six NbO6 octahedra and faces with two LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 2–15°. There are a spread of Nb–O bond distances ranging from 1.97–2.03 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six NbO6 octahedra and faces with three LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 3–17°. There are a spread of Nb–O bond distances ranging from 1.92–2.15 Å. In the third Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six NbO6 octahedra and faces with three LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 3–17°. There are a spread of Nb–O bond distances ranging from 1.90–2.13 Å. In the fourth Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six NbO6 octahedra and faces with three LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 3–18°. There are a spread of Nb–O bond distances ranging from 1.93–2.09 Å. In the fifth Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with six NbO6 octahedra and faces with three LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 4–18°. There are a spread of Nb–O bond distances ranging from 1.90–2.17 Å. In the sixth Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six NbO6 octahedra and faces with two LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 2–14°. There are a spread of Nb–O bond distances ranging from 1.94–2.07 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to two La3+ and two Nb5+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one La3+ and two Nb5+ atoms. In the third O2- site, O2- is bonded in a distorted linear geometry to one La3+ and two Nb5+ atoms. In the fourth O2- site, O2- is bonded in a 5-coordinate geometry to three La3+ and two Nb5+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to three La3+ and two Nb5+ atoms. In the sixth O2- site, O2- is bonded in a linear geometry to two Nb5+ atoms. In the seventh O2- site, O2- is bonded in a linear geometry to two Nb5+ atoms. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to two La3+ and two Nb5+ atoms. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to one La3+ and two Nb5+ atoms. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to one La3+ and two Nb5+ atoms. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to one La3+ and two Nb5+ atoms. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to two La3+ and two Nb5+ atoms. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to two La3+ and two Nb5+ atoms. In the fourteenth O2- site, O2- is bonded in a linear geometry to two Nb5+ atoms. In the fifteenth O2- site, O2- is bonded in a 4-coordinate geometry to two La3+ and two Nb5+ atoms. In the sixteenth O2- site, O2- is bonded in a 3-coordinate geometry to one La3+ and two Nb5+ atoms. In the seventeenth O2- site, O2- is bonded in a 3-coordinate geometry to one La3+ and two Nb5+ atoms. In the eighteenth O2- site, O2- is bonded in a 3-coordinate geometry to one La3+ and two Nb5+ atoms.