DOI: 10.17188/1321536
title: Materials Data on Ca2AlBiO5 by Materials Project

description: Ca2AlBiO5 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six O2- atoms to form distorted CaO6 pentagonal pyramids that share a cornercorner with one BiO6 octahedra, a cornercorner with one CaO4 tetrahedra, corners with four AlO4 tetrahedra, edges with two equivalent BiO6 octahedra, and a faceface with one BiO6 octahedra. The corner-sharing octahedral tilt angles are 79°. There are a spread of Ca–O bond distances ranging from 2.27–2.65 Å. In the second Ca2+ site, Ca2+ is bonded to four O2- atoms to form distorted CaO4 tetrahedra that share corners with two equivalent BiO6 octahedra, a cornercorner with one CaO6 pentagonal pyramid, corners with four AlO4 tetrahedra, and an edgeedge with one BiO6 octahedra. The corner-sharing octahedra tilt angles range from 60–89°. There are a spread of Ca–O bond distances ranging from 2.24–2.42 Å. In the third Ca2+ site, Ca2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Ca–O bond distances ranging from 2.23–2.47 Å. In the fourth Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.24–2.97 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two BiO6 octahedra, corners with two equivalent CaO6 pentagonal pyramids, corners with two equivalent CaO4 tetrahedra, and corners with two equivalent AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 51–52°. There are a spread of Al–O bond distances ranging from 1.77–1.87 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two BiO6 octahedra, corners with two equivalent CaO6 pentagonal pyramids, corners with two equivalent CaO4 tetrahedra, and corners with two equivalent AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–53°. There are a spread of Al–O bond distances ranging from 1.78–1.87 Å. There are two inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded to six O2- atoms to form distorted BiO6 octahedra that share corners with four equivalent BiO6 octahedra, a cornercorner with one CaO6 pentagonal pyramid, corners with two equivalent CaO4 tetrahedra, corners with two AlO4 tetrahedra, and a faceface with one CaO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 44–59°. There are a spread of Bi–O bond distances ranging from 2.20–2.76 Å. In the second Bi3+ site, Bi3+ is bonded to six O2- atoms to form distorted BiO6 octahedra that share corners with four equivalent BiO6 octahedra, corners with two AlO4 tetrahedra, edges with two equivalent CaO6 pentagonal pyramids, and an edgeedge with one CaO4 tetrahedra. The corner-sharing octahedra tilt angles range from 44–59°. There are a spread of Bi–O bond distances ranging from 2.24–2.77 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two Al3+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two Al3+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Al3+, and one Bi3+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Al3+, and one Bi3+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to three Ca2+, one Al3+, and one Bi3+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Al3+, and one Bi3+ atom. In the seventh O2- site, O2- is bonded to two Ca2+ and two Bi3+ atoms to form distorted corner-sharing OCa2Bi2 trigonal pyramids. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two Bi3+ atoms. In the ninth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Ca2+ and two Bi3+ atoms. In the tenth O2- site, O2- is bonded to two Ca2+ and two Bi3+ atoms to form distorted corner-sharing OCa2Bi2 trigonal pyramids.