Materials Data on BaTiFe2(SiO5)2 by Materials Project
BaTiFe2(SiO5)2 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Ba2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ba–O bond distances ranging from 2.81–2.86 Å. Ti4+ is bonded to five O2- atoms to form TiO5 square pyramids that share corners with four equivalent SiO4 tetrahedra. There are a spread of Ti–O bond distances ranging from 1.73–1.95 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent SiO4 tetrahedra and edges with two equivalent FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.08–2.18 Å. In the second Fe3+ site, Fe3+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Fe–O bond distances ranging from 1.90–2.02 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one FeO6 octahedra, corners with two equivalent TiO5 square pyramids, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. There are a spread of Si–O bond distances ranging from 1.60–1.67 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two Fe3+ and one Si4+ atom. In the second O2- site, O2- is bonded in a trigonal non-coplanar geometry to three Fe3+ atoms. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ba2+, one Ti4+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ba2+, one Ti4+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a linear geometry to two equivalent Si4+ atoms. In the sixth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three Fe3+ atoms. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Ba2+ and one Ti4+ atom.