DOI: 10.17188/1652028
title: Materials Data on Tm2Si2O7 by Materials Project

description: Tm2Si2O7 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are twelve inequivalent Tm3+ sites. In the first Tm3+ site, Tm3+ is bonded to six O2- atoms to form distorted TmO6 octahedra that share corners with seven SiO4 tetrahedra. There are a spread of Tm–O bond distances ranging from 2.17–2.38 Å. In the second Tm3+ site, Tm3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Tm–O bond distances ranging from 2.16–2.82 Å. In the third Tm3+ site, Tm3+ is bonded to six O2- atoms to form distorted TmO6 octahedra that share corners with seven SiO4 tetrahedra. There are a spread of Tm–O bond distances ranging from 2.18–2.38 Å. In the fourth Tm3+ site, Tm3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Tm–O bond distances ranging from 2.23–2.71 Å. In the fifth Tm3+ site, Tm3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Tm–O bond distances ranging from 2.27–2.54 Å. In the sixth Tm3+ site, Tm3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Tm–O bond distances ranging from 2.28–2.53 Å. In the seventh Tm3+ site, Tm3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Tm–O bond distances ranging from 2.24–2.65 Å. In the eighth Tm3+ site, Tm3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Tm–O bond distances ranging from 2.22–2.64 Å. In the ninth Tm3+ site, Tm3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Tm–O bond distances ranging from 2.20–2.65 Å. In the tenth Tm3+ site, Tm3+ is bonded to seven O2- atoms to form distorted TmO7 pentagonal bipyramids that share corners with five SiO4 tetrahedra and an edgeedge with one SiO4 tetrahedra. There are a spread of Tm–O bond distances ranging from 2.21–2.43 Å. In the eleventh Tm3+ site, Tm3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Tm–O bond distances ranging from 2.21–2.40 Å. In the twelfth Tm3+ site, Tm3+ is bonded in a 7-coordinate geometry to eight O2- atoms. There are a spread of Tm–O bond distances ranging from 2.23–2.82 Å. There are twelve inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one TmO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 57°. There are a spread of Si–O bond distances ranging from 1.61–1.74 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one TmO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 58°. There are a spread of Si–O bond distances ranging from 1.63–1.73 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent TmO7 pentagonal bipyramids and a cornercorner with one SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.74 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three equivalent TmO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 60–68°. There are a spread of Si–O bond distances ranging from 1.61–1.67 Å. In the fifth Si4+ site, Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.73 Å. In the sixth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three equivalent TmO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 59–68°. There are a spread of Si–O bond distances ranging from 1.61–1.67 Å. In the seventh Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one TmO6 octahedra. The corner-sharing octahedral tilt angles are 56°. There are a spread of Si–O bond distances ranging from 1.62–1.66 Å. In the eighth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent TmO7 pentagonal bipyramids. There are a spread of Si–O bond distances ranging from 1.62–1.68 Å. In the ninth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one TmO6 octahedra and an edgeedge with one TmO7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 53°. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. In the tenth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent TmO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–63°. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. In the eleventh Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one TmO7 pentagonal bipyramid and a cornercorner with one SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.62–1.69 Å. In the twelfth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent TmO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–64°. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. There are forty-two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Tm3+ and two Si4+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Tm3+ and one Si4+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two Tm3+ and one Si4+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Tm3+ and two Si4+ atoms. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Tm3+ and one Si4+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Tm3+ and one Si4+ atom. In the seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two Tm3+ and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Tm3+ and two Si4+ atoms. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to two Tm3+ and one Si4+ atom. In the tenth O2- site, O2- is bonded in a 1-coordinate geometry to two Tm3+ and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two Tm3+ and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Tm3+ and one Si4+ atom. In the thirteenth O2- site, O2- is bonded in a 1-coordinate geometry to two Tm3+ and one Si4+ atom. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Tm3+ and one Si4+ atom. In the fifteenth O2- site, O2- is bonded in a 1-coordinate geometry to three Tm3+ and one Si4+ atom. In the sixteenth O2- site, O2- is bonded in a 1-coordinate geometry to two Tm3+ and one Si4+ atom. In the seventeenth O2- site, O2- is bonded in a 2-coordinate geometry to two Tm3+ and two Si4+ atoms. In the eighteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Tm3+ and one Si4+ atom. In the nineteenth O2- site, O2- is bonded in a bent 120 degrees geometry to two Si4+ atoms. In the twentieth O2- site, O2- is bonded in a 1-coordinate geometry to three Tm3+ and one Si4+ atom. In the twenty-first O2- site, O2- is bonded in a 3-coordinate geometry to two Tm3+ and one Si4+ atom. In the twenty-second O2- site, O2- is bonded in a 4-coordinate geometry to three Tm3+ and one Si4+ atom. In the twenty-third O2- site, O2- is bonded in a bent 120 degrees geometry to two Si4+ atoms. In the twenty-fourth O2- site, O2- is bonded in a 1-coordinate geometry to three Tm3+ and one Si4+ atom. In the twenty-fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Tm3+ and one Si4+ atom. In the twenty-sixth O2- site, O2- is bonded in a 3-coordinate geometry to two Tm3+ and one Si4+ atom. In the twenty-seventh O2- site, O2- is bonded in a 4-coordinate geometry to three Tm3+ and one Si4+ atom. In the twenty-eighth O2- site, O2- is bonded in a 3-coordinate geometry to two Tm3+ and one Si4+ atom. In the twenty-ninth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Tm3+ and one Si4+ atom. In the thirtieth O2- site, O2- is bonded in a 1-coordinate geometry to two Tm3+ and one Si4+ atom. In the thirty-first O2- site, O2- is bonded in a 1-coordinate geometry to three Tm3+ and one Si4+ atom. In the thirty-second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Tm3+ and one Si4+ atom. In the thirty-third O2- site, O2- is bonded in a 3-coordinate geometry to two Tm3+ and one Si4+ atom. In the thirty-fourth O2- site, O2- is bonded in a 1-coordinate geometry to three Tm3+ and one Si4+ atom. In the thirty-fifth O2- site, O2- is bonded in a 3-coordinate geometry to two Tm3+ and one Si4+ atom. In the thirty-sixth O2- site, O2- is bonded in a 1-coordinate geometry to three Tm3+ and one Si4+ atom. In the thirty-seventh O2- site, O2- is bonded in a 4-coordinate geometry to three Tm3+ and one Si4+ atom. In the thirty-eighth O2- site, O2- is bonded in a 3-coordinate geometry to two Tm3+ and one Si4+ atom. In the thirty-ninth O2- site, O2- is bonded in a 1-coordinate geometry to three Tm3+ and one Si4+ atom. In the fortieth O2- site, O2- is bonded in a 1-coordinate geometry to three Tm3+ and one Si4+ atom. In the forty-first O2- site, O2- is bonded in a 4-coordinate geometry to three Tm3+ and one Si4+ atom. In the forty-second O2- site, O2- is bonded in a 4-coordinate geometry to three Tm3+ and one Si4+ atom.