Materials Data on CrBi8O15 by Materials Project
Bi8(CrO4)O11 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are two inequivalent Cr6+ sites. In the first Cr6+ site, Cr6+ is bonded to four O2- atoms to form CrO4 tetrahedra that share corners with four equivalent BiO6 octahedra. The corner-sharing octahedra tilt angles range from 58–73°. There are a spread of Cr–O bond distances ranging from 1.66–1.68 Å. In the second Cr6+ site, Cr6+ is bonded to four O2- atoms to form CrO4 tetrahedra that share corners with two equivalent BiO6 octahedra. The corner-sharing octahedral tilt angles are 54°. There is three shorter (1.67 Å) and one longer (1.68 Å) Cr–O bond length. There are ten inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded in a 4-coordinate geometry to four O2- atoms. There are two shorter (2.21 Å) and two longer (2.31 Å) Bi–O bond lengths. In the second Bi3+ site, Bi3+ is bonded to six O2- atoms to form distorted BiO6 octahedra that share a cornercorner with one BiO6 octahedra, corners with three CrO4 tetrahedra, and an edgeedge with one BiO6 octahedra. The corner-sharing octahedral tilt angles are 48°. There are a spread of Bi–O bond distances ranging from 2.13–2.94 Å. In the third Bi3+ site, Bi3+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Bi–O bond distances ranging from 2.15–2.48 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 2.17–2.75 Å. In the fifth Bi3+ site, Bi3+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Bi–O bond distances ranging from 2.14–2.83 Å. In the sixth 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 2.14–3.10 Å. In the seventh Bi3+ site, Bi3+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Bi–O bond distances ranging from 2.29–2.92 Å. In the eighth Bi3+ site, Bi3+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Bi–O bond distances ranging from 2.10–2.95 Å. In the ninth 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 2.20–2.86 Å. In the tenth 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 2.14–2.86 Å. There are twenty inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three Bi3+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to four Bi3+ atoms. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one Cr6+ and two equivalent Bi3+ atoms. In the fourth O2- site, O2- is bonded in a trigonal non-coplanar geometry to three Bi3+ atoms. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to one Cr6+ and three Bi3+ atoms. In the sixth O2- site, O2- is bonded in a single-bond geometry to one Cr6+ and three Bi3+ atoms. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to one Cr6+ and two Bi3+ atoms. In the eighth O2- site, O2- is bonded in a trigonal non-coplanar geometry to three Bi3+ atoms. In the ninth O2- site, O2- is bonded in a trigonal non-coplanar geometry to three Bi3+ atoms. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to four Bi3+ atoms. In the eleventh O2- site, O2- is bonded to four Bi3+ atoms to form distorted edge-sharing OBi4 tetrahedra. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to four Bi3+ atoms. In the thirteenth O2- site, O2- is bonded in a single-bond geometry to one Cr6+ and two equivalent Bi3+ atoms. In the fourteenth O2- site, O2- is bonded in a single-bond geometry to one Cr6+ atom. In the fifteenth O2- site, O2- is bonded in a 3-coordinate geometry to three Bi3+ atoms. In the sixteenth O2- site, O2- is bonded in a 4-coordinate geometry to four Bi3+ atoms. In the seventeenth O2- site, O2- is bonded in a 2-coordinate geometry to four Bi3+ atoms. In the eighteenth O2- site, O2- is bonded to four Bi3+ atoms to form distorted edge-sharing OBi4 tetrahedra. In the nineteenth O2- site, O2- is bonded to four Bi3+ atoms to form distorted edge-sharing OBi4 tetrahedra. In the twentieth O2- site, O2- is bonded in a 3-coordinate geometry to three Bi3+ atoms.