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Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Ti2CrFe3(PO4)6 crystallizes in the trigonal R3 space group. The structure is three-dimensional. there are two inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six PO4 tetrahedra, a faceface with one CrO6 octahedra, and a faceface with one FeO6 octahedra. There are three shorter (1.99 Å) and three longer (2.13 Å) Ti–O bond lengths. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six PO4 tetrahedra and faces with two FeO6 octahedra. There are three shorter (2.01 Å) and three longer (2.08 Å) Ti–O bond lengths. Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one TiO6 octahedra. There is three shorter (1.95 Å) and three longer (2.04 Å) Cr–O bond length. There are three inequivalent Fe+2.33+ sites. In the first Fe+2.33+ site, Fe+2.33+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one TiO6 octahedra. There are three shorter (1.98 Å) and three longer (2.17 Å) Fe–O bond lengths. In the second Fe+2.33+ site, Fe+2.33+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one TiO6 octahedra. There are three shorter (1.99 Å) and three longer (2.17 Å) Fe–O bond lengths. In the third Fe+2.33+ site, Fe+2.33+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one TiO6 octahedra. There are three shorter (1.92 Å) and three longer (2.13 Å) Fe–O bond lengths. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one CrO6 octahedra, corners with two TiO6 octahedra, and corners with three FeO6 octahedra. The corner-sharing octahedra tilt angles range from 28–55°. There are a spread of P–O bond distances ranging from 1.51–1.59 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one CrO6 octahedra, corners with two TiO6 octahedra, and corners with three FeO6 octahedra. The corner-sharing octahedra tilt angles range from 32–56°. There are a spread of P–O bond distances ranging from 1.51–1.61 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe+2.33+ and one P5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Ti4+, one Fe+2.33+, and one P5+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Cr3+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Ti4+, one Fe+2.33+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe+2.33+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Ti4+, one Cr3+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Ti4+, one Fe+2.33+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe+2.33+ and one P5+ atom.
TiCr2Fe3(PO4)6 crystallizes in the trigonal R3 space group. The structure is three-dimensional. Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six PO4 tetrahedra. There is three shorter (1.88 Å) and three longer (2.07 Å) Ti–O bond length. There are two inequivalent Cr3+ sites. In the first Cr3+ site, Cr3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.17 Å) and three longer (2.19 Å) Cr–O bond lengths. In the second Cr3+ site, Cr3+ is bonded to six O2- atoms to form distorted CrO6 octahedra that share corners with six PO4 tetrahedra and faces with two FeO6 octahedra. There are three shorter (2.14 Å) and three longer (2.15 Å) Cr–O bond lengths. There are three inequivalent Fe+2.67+ sites. In the first Fe+2.67+ site, Fe+2.67+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share corners with six PO4 tetrahedra. There are three shorter (1.93 Å) and three longer (2.10 Å) Fe–O bond lengths. In the second Fe+2.67+ site, Fe+2.67+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one CrO6 octahedra. There are three shorter (1.94 Å) and three longer (2.14 Å) Fe–O bond lengths. In the third Fe+2.67+ site, Fe+2.67+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one CrO6 octahedra. There are three shorter (1.93 Å) and three longer (2.10 Å) Fe–O bond lengths. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one TiO6 octahedra, a cornercorner with one CrO6 octahedra, and corners with three FeO6 octahedra. The corner-sharing octahedra tilt angles range from 29–51°. There are a spread of P–O bond distances ranging from 1.52–1.58 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one TiO6 octahedra, a cornercorner with one CrO6 octahedra, and corners with three FeO6 octahedra. The corner-sharing octahedra tilt angles range from 24–53°. There are a spread of P–O bond distances ranging from 1.52–1.56 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe+2.67+ and one P5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Cr3+, one Fe+2.67+, and one P5+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Ti4+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Cr3+, one Fe+2.67+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe+2.67+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Ti4+, one Cr3+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Cr3+, one Fe+2.67+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe+2.67+ and one P5+ atom.