DOE OSTI2020
MnFe3(BiO3)4 is Ilmenite-derived structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. Mn3+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with six FeO6 octahedra. The corner-sharing octahedra tilt angles range from 27–31°. There are a spread of Mn–O bond distances ranging from 1.95–2.29 Å. There are three inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with three equivalent MnO6 octahedra and corners with three equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 25–31°. There are a spread of Fe–O bond distances ranging from 1.96–2.18 Å. In the second Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with three equivalent MnO6 octahedra and corners with three equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 26–29°. There are a spread of Fe–O bond distances ranging from 2.00–2.15 Å. In the third Fe3+ site, Fe3+ is bonded to six O2- atoms to form corner-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 25–29°. There are a spread of Fe–O bond distances ranging from 1.98–2.22 Å. There are four 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 2.28–2.53 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 2.29–2.57 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 2.32–2.51 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 2.34–2.56 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted see-saw-like geometry to one Mn3+, one Fe3+, and two Bi3+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Fe3+ and two Bi3+ atoms. In the third O2- site, O2- is bonded in a distorted see-saw-like geometry to one Mn3+, one Fe3+, and two Bi3+ atoms. In the fourth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Fe3+ and two Bi3+ atoms. In the fifth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Fe3+ and two Bi3+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Mn3+, one Fe3+, and two Bi3+ atoms. In the seventh O2- site, O2- is bonded in a distorted see-saw-like geometry to one Mn3+, one Fe3+, and two Bi3+ atoms. In the eighth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Fe3+ and two Bi3+ atoms. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to one Mn3+, one Fe3+, and two Bi3+ atoms. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to two Fe3+ and two Bi3+ atoms. In the eleventh O2- site, O2- is bonded in a distorted see-saw-like geometry to two Fe3+ and two Bi3+ atoms. In the twelfth O2- site, O2- is bonded in a distorted tetrahedral geometry to one Mn3+, one Fe3+, and two Bi3+ atoms.