DOE OSTI2020
Sc2Ti2O7 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are eight inequivalent Sc3+ sites. In the first Sc3+ site, Sc3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sc–O bond distances ranging from 2.14–2.72 Å. In the second Sc3+ site, Sc3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sc–O bond distances ranging from 2.08–2.48 Å. In the third Sc3+ site, Sc3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sc–O bond distances ranging from 2.08–2.48 Å. In the fourth Sc3+ site, Sc3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sc–O bond distances ranging from 2.10–2.60 Å. In the fifth Sc3+ site, Sc3+ is bonded in a 6-coordinate geometry to seven O2- atoms. There are a spread of Sc–O bond distances ranging from 2.12–2.66 Å. In the sixth Sc3+ site, Sc3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sc–O bond distances ranging from 2.08–2.50 Å. In the seventh Sc3+ site, Sc3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sc–O bond distances ranging from 2.11–2.26 Å. In the eighth Sc3+ site, Sc3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sc–O bond distances ranging from 2.06–2.61 Å. There are eight inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form corner-sharing TiO6 octahedra. The corner-sharing octahedra tilt angles range from 42–54°. There are a spread of Ti–O bond distances ranging from 1.81–2.11 Å. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form distorted corner-sharing TiO6 octahedra. The corner-sharing octahedra tilt angles range from 33–54°. There are a spread of Ti–O bond distances ranging from 1.84–2.34 Å. In the third Ti4+ site, Ti4+ is bonded to six O2- atoms to form corner-sharing TiO6 octahedra. The corner-sharing octahedra tilt angles range from 36–49°. There are a spread of Ti–O bond distances ranging from 1.83–2.18 Å. In the fourth Ti4+ site, Ti4+ is bonded to six O2- atoms to form distorted corner-sharing TiO6 octahedra. The corner-sharing octahedra tilt angles range from 34–53°. There are a spread of Ti–O bond distances ranging from 1.84–2.28 Å. In the fifth Ti4+ site, Ti4+ is bonded to six O2- atoms to form corner-sharing TiO6 octahedra. The corner-sharing octahedra tilt angles range from 43–53°. There are a spread of Ti–O bond distances ranging from 1.81–2.11 Å. In the sixth Ti4+ site, Ti4+ is bonded to six O2- atoms to form corner-sharing TiO6 octahedra. The corner-sharing octahedra tilt angles range from 41–48°. There are a spread of Ti–O bond distances ranging from 1.84–2.06 Å. In the seventh Ti4+ site, Ti4+ is bonded to six O2- atoms to form distorted corner-sharing TiO6 octahedra. The corner-sharing octahedra tilt angles range from 35–50°. There are a spread of Ti–O bond distances ranging from 1.82–2.18 Å. In the eighth Ti4+ site, Ti4+ is bonded to six O2- atoms to form corner-sharing TiO6 octahedra. The corner-sharing octahedra tilt angles range from 39–48°. There are a spread of Ti–O bond distances ranging from 1.87–2.06 Å. There are twenty-eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Sc3+ and two equivalent Ti4+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two Sc3+ and two Ti4+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Sc3+ and two Ti4+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Sc3+ and two Ti4+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to three Sc3+ and one Ti4+ atom. In the sixth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Sc3+ and two Ti4+ atoms. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to two Sc3+ and one Ti4+ atom. In the eighth O2- site, O2- is bonded in a distorted trigonal pyramidal geometry to two Sc3+ and two Ti4+ atoms. In the ninth O2- site, O2- is bonded in a 5-coordinate geometry to three Sc3+ and two equivalent Ti4+ atoms. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to two Sc3+ and two Ti4+ atoms. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to two Sc3+ and two equivalent Ti4+ atoms. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to three Sc3+ and one Ti4+ atom. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Sc3+ and one Ti4+ atom. In the fourteenth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Sc3+ and two Ti4+ atoms. In the fifteenth O2- site, O2- is bonded in a distorted trigonal pyramidal geometry to two Sc3+ and two Ti4+ atoms. In the sixteenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Sc3+ and two Ti4+ atoms. In the seventeenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Sc3+ and two Ti4+ atoms. In the eighteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Sc3+ and one Ti4+ atom. In the nineteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Sc3+ and one Ti4+ atom. In the twentieth O2- site, O2- is bonded in a 4-coordinate geometry to two Sc3+ and two Ti4+ atoms. In the twenty-first O2- site, O2- is bonded in a 4-coordinate geometry to two Sc3+ and two Ti4+ atoms. In the twenty-second O2- site, O2- is bonded in a 4-coordinate geometry to two Sc3+ and two equivalent Ti4+ atoms. In the twenty-third O2- site, O2- is bonded in a 4-coordinate geometry to two Sc3+ and two Ti4+ atoms. In the twenty-fourth O2- site, O2- is bonded in a distorted T-shaped geometry to one Sc3+ and two Ti4+ atoms. In the twenty-fifth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Sc3+ and two Ti4+ atoms. In the twenty-sixth O2- site, O2- is bonded in a 4-coordinate geometry to three Sc3+ and one Ti4+ atom. In the twenty-seventh O2- site, O2- is bonded in a 3-coordinate geometry to three Sc3+ and one Ti4+ atom. In the twenty-eighth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Sc3+ and two Ti4+ atoms.