Materials Data on NaCa2Nb8(BiO4)9 by Materials Project
NaCa2Nb8(BiO4)9 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.42–2.75 Å. There are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.36–2.59 Å. In the second Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.37–2.58 Å. There are four inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 25–33°. There are a spread of Nb–O bond distances ranging from 1.88–2.23 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 29–33°. There are a spread of Nb–O bond distances ranging from 1.90–2.24 Å. In the third Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 31–33°. There are a spread of Nb–O bond distances ranging from 1.90–2.20 Å. In the fourth Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 27–33°. There are a spread of Nb–O bond distances ranging from 1.89–2.18 Å. There are five inequivalent Bi3+ sites. In the first 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 2.21–2.63 Å. In the second 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 2.21–2.61 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 2.21–2.59 Å. In the fourth 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 2.20–2.60 Å. In the fifth Bi3+ site, Bi3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Bi–O bond distances ranging from 2.25–2.66 Å. There are twenty inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted see-saw-like geometry to one Na1+, two equivalent Nb5+, and one Bi3+ atom. In the second O2- site, O2- is bonded to two Ca2+ and two equivalent Nb5+ atoms to form distorted corner-sharing OCa2Nb2 tetrahedra. In the third O2- site, O2- is bonded to two Ca2+ and two equivalent Nb5+ atoms to form distorted corner-sharing OCa2Nb2 tetrahedra. In the fourth O2- site, O2- is bonded in a distorted tetrahedral geometry to one Na1+, two equivalent Nb5+, and one Bi3+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two Nb5+ and one Bi3+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+ and two Nb5+ atoms. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+ and two Nb5+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+ and two Nb5+ atoms. In the ninth O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, two Nb5+, and one Bi3+ atom. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two Nb5+ atoms. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two Nb5+ atoms. In the twelfth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, two Nb5+, and one Bi3+ atom. In the thirteenth O2- site, O2- is bonded to four Bi3+ atoms to form a mixture of distorted edge and corner-sharing OBi4 tetrahedra. In the fourteenth O2- site, O2- is bonded to four Bi3+ atoms to form a mixture of distorted edge and corner-sharing OBi4 tetrahedra. In the fifteenth O2- site, O2- is bonded to four Bi3+ atoms to form a mixture of distorted edge and corner-sharing OBi4 tetrahedra. In the sixteenth O2- site, O2- is bonded to four Bi3+ atoms to form a mixture of distorted edge and corner-sharing OBi4 tetrahedra. In the seventeenth O2- site, O2- is bonded in a 1-coordinate geometry to one Nb5+ and two Bi3+ atoms. In the eighteenth O2- site, O2- is bonded in a 1-coordinate geometry to one Nb5+ and two Bi3+ atoms. In the nineteenth O2- site, O2- is bonded in a 1-coordinate geometry to one Nb5+ and two Bi3+ atoms. In the twentieth O2- site, O2- is bonded in a distorted single-bond geometry to one Nb5+ and two Bi3+ atoms.