DOI: 10.17188/1707638
title: Materials Data on Na3YbSi2O7 by Materials Project

description: Na3YbSi2O7 crystallizes in the trigonal P31c space group. The structure is three-dimensional. there are eleven inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to five O2- atoms to form distorted NaO5 trigonal bipyramids that share corners with six SiO4 tetrahedra, a cornercorner with one NaO4 trigonal pyramid, and edges with two equivalent YbO6 octahedra. There are a spread of Na–O bond distances ranging from 2.38–2.65 Å. In the second Na1+ site, Na1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Na–O bond distances ranging from 2.36–2.44 Å. In the third Na1+ site, Na1+ is bonded in a 4-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.30–2.89 Å. In the fourth Na1+ site, Na1+ is bonded in a 4-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.35–2.88 Å. In the fifth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.34–2.98 Å. In the sixth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 trigonal pyramids that share corners with two YbO6 octahedra, corners with four SiO4 tetrahedra, a cornercorner with one NaO5 trigonal bipyramid, and an edgeedge with one YbO6 octahedra. The corner-sharing octahedra tilt angles range from 76–78°. There are a spread of Na–O bond distances ranging from 2.33–2.40 Å. In the seventh Na1+ site, Na1+ is bonded in a 4-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.29–2.97 Å. In the eighth Na1+ site, Na1+ is bonded in a 4-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.31–2.88 Å. In the ninth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.51 Å) and three longer (2.55 Å) Na–O bond lengths. In the tenth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.61 Å) and three longer (2.83 Å) Na–O bond lengths. In the eleventh Na1+ site, Na1+ is bonded in a distorted hexagonal planar geometry to six O2- atoms. There are three shorter (2.61 Å) and three longer (2.67 Å) Na–O bond lengths. There are five inequivalent Yb3+ sites. In the first Yb3+ site, Yb3+ is bonded to six O2- atoms to form YbO6 octahedra that share corners with six SiO4 tetrahedra and an edgeedge with one NaO4 trigonal pyramid. There are a spread of Yb–O bond distances ranging from 2.27–2.35 Å. In the second Yb3+ site, Yb3+ is bonded to six O2- atoms to form YbO6 octahedra that share corners with six SiO4 tetrahedra, a cornercorner with one NaO4 trigonal pyramid, and edges with two equivalent NaO5 trigonal bipyramids. There are a spread of Yb–O bond distances ranging from 2.26–2.38 Å. In the third Yb3+ site, Yb3+ is bonded to six O2- atoms to form distorted YbO6 octahedra that share corners with six SiO4 tetrahedra. There are three shorter (2.32 Å) and three longer (2.33 Å) Yb–O bond lengths. In the fourth Yb3+ site, Yb3+ is bonded to six O2- atoms to form distorted YbO6 pentagonal pyramids that share corners with six SiO4 tetrahedra. There are three shorter (2.34 Å) and three longer (2.35 Å) Yb–O bond lengths. In the fifth Yb3+ site, Yb3+ is bonded to six O2- atoms to form distorted YbO6 octahedra that share corners with six SiO4 tetrahedra and corners with three equivalent NaO4 trigonal pyramids. There are three shorter (2.33 Å) and three longer (2.35 Å) Yb–O bond lengths. There are six inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three YbO6 octahedra, a cornercorner with one SiO4 tetrahedra, a cornercorner with one NaO5 trigonal bipyramid, and corners with two equivalent NaO4 trigonal pyramids. The corner-sharing octahedra tilt angles range from 31–54°. There is three shorter (1.63 Å) and one longer (1.69 Å) Si–O bond length. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three YbO6 octahedra, a cornercorner with one SiO4 tetrahedra, a cornercorner with one NaO5 trigonal bipyramid, and a cornercorner with one NaO4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 31–53°. There are a spread of Si–O bond distances ranging from 1.63–1.69 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three YbO6 octahedra, a cornercorner with one SiO4 tetrahedra, and a cornercorner with one NaO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 26–53°. There is three shorter (1.63 Å) and one longer (1.69 Å) Si–O bond length. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three YbO6 octahedra, a cornercorner with one SiO4 tetrahedra, and a cornercorner with one NaO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 29–51°. There are a spread of Si–O bond distances ranging from 1.63–1.69 Å. In the fifth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two YbO6 octahedra, a cornercorner with one YbO6 pentagonal pyramid, a cornercorner with one SiO4 tetrahedra, a cornercorner with one NaO5 trigonal bipyramid, and a cornercorner with one NaO4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 37–43°. There are a spread of Si–O bond distances ranging from 1.63–1.69 Å. In the sixth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two YbO6 octahedra, a cornercorner with one YbO6 pentagonal pyramid, a cornercorner with one SiO4 tetrahedra, and a cornercorner with one NaO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 24–43°. There is three shorter (1.63 Å) and one longer (1.69 Å) Si–O bond length. There are twenty-one inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Yb3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 5-coordinate geometry to three Na1+, one Yb3+, and one Si4+ atom. In the third O2- site, O2- is bonded to two Na1+, one Yb3+, and one Si4+ atom to form distorted corner-sharing ONa2YbSi tetrahedra. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+ and two Si4+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Yb3+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+, one Yb3+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Yb3+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Yb3+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Yb3+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a 1-coordinate geometry to four Na1+, one Yb3+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a trigonal planar geometry to one Na1+ and two Si4+ atoms. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Yb3+, and one Si4+ atom. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Yb3+, and one Si4+ atom. In the fourteenth O2- site, O2- is bonded to two Na1+, one Yb3+, and one Si4+ atom to form distorted corner-sharing ONa2YbSi tetrahedra. In the fifteenth O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Yb3+, and one Si4+ atom. In the sixteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Yb3+, and one Si4+ atom. In the seventeenth O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Yb3+, and one Si4+ atom. In the eighteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+ and two Si4+ atoms. In the nineteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Yb3+, and one Si4+ atom. In the twentieth O2- site, O2- is bonded to two Na1+, one Yb3+, and one Si4+ atom to form distorted corner-sharing ONa2YbSi tetrahedra. In the twenty-first O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Yb3+, and one Si4+ atom.