DOE OSTI2020
Na10Zn4O9 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are twelve inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with two equivalent NaO4 tetrahedra, corners with two equivalent NaO5 trigonal bipyramids, corners with two equivalent NaO4 trigonal pyramids, and edges with six ZnO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.58–2.90 Å. In the second Na1+ site, Na1+ is bonded to five O2- atoms to form distorted NaO5 trigonal bipyramids that share a cornercorner with one NaO6 octahedra, a cornercorner with one NaO4 tetrahedra, corners with two ZnO4 tetrahedra, a cornercorner with one NaO4 trigonal pyramid, edges with two NaO4 tetrahedra, edges with two ZnO4 tetrahedra, and an edgeedge with one NaO4 trigonal pyramid. The corner-sharing octahedral tilt angles are 43°. There are a spread of Na–O bond distances ranging from 2.41–2.68 Å. In the third Na1+ site, Na1+ is bonded in a 3-coordinate geometry to four O2- atoms. There are a spread of Na–O bond distances ranging from 2.28–2.74 Å. In the fourth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 trigonal pyramids that share a cornercorner with one NaO6 octahedra, corners with two NaO4 tetrahedra, corners with four ZnO4 tetrahedra, a cornercorner with one NaO5 trigonal bipyramid, an edgeedge with one NaO4 tetrahedra, and an edgeedge with one NaO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 83°. There are a spread of Na–O bond distances ranging from 2.23–2.64 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 2.48–2.83 Å. In the sixth Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share a cornercorner with one NaO4 tetrahedra, corners with four ZnO4 tetrahedra, a cornercorner with one NaO5 trigonal bipyramid, a cornercorner with one NaO4 trigonal pyramid, an edgeedge with one NaO5 trigonal bipyramid, and an edgeedge with one NaO4 trigonal pyramid. There are a spread of Na–O bond distances ranging from 2.29–2.35 Å. In the seventh 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 2.32–2.41 Å. In the eighth Na1+ site, Na1+ is bonded in a 2-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.35–2.71 Å. In the ninth Na1+ site, Na1+ is bonded in a 3-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.35–2.90 Å. In the tenth 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 2.35–2.53 Å. In the eleventh 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 2.28–2.61 Å. In the twelfth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with two equivalent NaO6 octahedra, corners with two equivalent NaO4 tetrahedra, corners with four ZnO4 tetrahedra, corners with two equivalent NaO4 trigonal pyramids, and edges with two equivalent NaO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 41°. There are two shorter (2.36 Å) and two longer (2.51 Å) Na–O bond lengths. There are four inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share corners with two ZnO4 tetrahedra, corners with three NaO4 tetrahedra, a cornercorner with one NaO5 trigonal bipyramid, corners with two equivalent NaO4 trigonal pyramids, an edgeedge with one NaO6 octahedra, an edgeedge with one ZnO4 tetrahedra, and an edgeedge with one NaO5 trigonal bipyramid. There are a spread of Zn–O bond distances ranging from 1.98–2.07 Å. In the second Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share corners with two NaO4 tetrahedra, corners with two ZnO4 tetrahedra, a cornercorner with one NaO4 trigonal pyramid, an edgeedge with one NaO6 octahedra, an edgeedge with one ZnO4 tetrahedra, and an edgeedge with one NaO5 trigonal bipyramid. There are a spread of Zn–O bond distances ranging from 1.98–2.08 Å. In the third Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share a cornercorner with one NaO4 tetrahedra, corners with two ZnO4 tetrahedra, a cornercorner with one NaO5 trigonal bipyramid, a cornercorner with one NaO4 trigonal pyramid, an edgeedge with one NaO6 octahedra, and an edgeedge with one ZnO4 tetrahedra. There are a spread of Zn–O bond distances ranging from 1.97–2.07 Å. In the fourth Zn2+ site, Zn2+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of Zn–O bond distances ranging from 1.92–1.97 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to five Na1+ and two Zn2+ atoms. In the second O2- site, O2- is bonded in a 5-coordinate geometry to five Na1+ and two equivalent Zn2+ atoms. In the third O2- site, O2- is bonded to six Na1+ and one Zn2+ atom to form distorted ONa6Zn pentagonal bipyramids that share a cornercorner with one ONa6Zn pentagonal bipyramid and an edgeedge with one ONa4Zn2 trigonal bipyramid. In the fourth O2- site, O2- is bonded in a 7-coordinate geometry to five Na1+ and two Zn2+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to four Na1+ and two Zn2+ atoms. In the sixth O2- site, O2- is bonded to four Na1+ and two Zn2+ atoms to form distorted edge-sharing ONa4Zn2 trigonal bipyramids. In the seventh O2- site, O2- is bonded in a 7-coordinate geometry to six Na1+ and one Zn2+ atom. In the eighth O2- site, O2- is bonded in a 7-coordinate geometry to six Na1+ and one Zn2+ atom. In the ninth O2- site, O2- is bonded in a 7-coordinate geometry to five Na1+ and two Zn2+ atoms.