Materials Data on Na5GdO4 by Materials Project

Abstract

Na5GdO4 crystallizes in the tetragonal P4_2/nmc space group. The structure is three-dimensional. there are six inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to four equivalent O2- atoms to form distorted NaO4 tetrahedra that share corners with two equivalent NaO4 tetrahedra, corners with four equivalent GdO4 tetrahedra, corners with four equivalent NaO4 trigonal pyramids, edges with three NaO4 tetrahedra, and edges with two equivalent NaO4 trigonal pyramids. There are two shorter (2.23 Å) and two longer (2.54 Å) Na–O bond lengths. In the second Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 trigonal pyramids that share corners with two equivalent GdO4 tetrahedra, corners with six NaO4 tetrahedra, corners with four equivalent NaO4 trigonal pyramids, an edgeedge with one GdO4 tetrahedra, edges with two NaO4 tetrahedra, and edges with two equivalent NaO4 trigonal pyramids. There are a spread of Na–O bond distances ranging from 2.25–2.52 Å. In the third Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share corners with four equivalent GdO4 tetrahedra, corners with six NaO4 tetrahedra, corners with four equivalent NaO4 trigonal pyramids, and edges with two NaO4 tetrahedra. There are two shorter (2.38 Å) and two longer (2.40 Å) Na–O bond lengths. In the fourth Na1+ site, Na1+ is bonded to four equivalent O2- atoms to form NaO4 tetrahedra that share corners with four equivalent GdO4 tetrahedra, corners with eight equivalent NaO4 trigonal pyramids, edges with two equivalent NaO4 tetrahedra, and edges with four equivalent NaO4 trigonal pyramids. There are two shorter (2.34 Å) and two longer (2.40 Å) Na–O bond lengths. In the fifth Na1+ site, Na1+ is bonded to four equivalent O2- atoms to form NaO4 tetrahedra that share corners with four equivalent GdO4 tetrahedra, corners with eight equivalent NaO4 tetrahedra, and edges with two equivalent NaO4 tetrahedra. All Na–O bond lengths are 2.38 Å. In the sixth Na1+ site, Na1+ is bonded to four equivalent O2- atoms to form NaO4 tetrahedra that share corners with four equivalent GdO4 tetrahedra and edges with six NaO4 tetrahedra. All Na–O bond lengths are 2.43 Å. Gd3+ is bonded to four O2- atoms to form GdO4 tetrahedra that share corners with twelve NaO4 tetrahedra, corners with four equivalent NaO4 trigonal pyramids, and edges with two equivalent NaO4 trigonal pyramids. There are a spread of Gd–O bond distances ranging from 2.21–2.27 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to five Na1+ and one Gd3+ atom to form distorted ONa5Gd octahedra that share corners with two equivalent ONa5Gd octahedra, a cornercorner with one ONa6Gd pentagonal bipyramid, edges with four equivalent ONa5Gd octahedra, and edges with two equivalent ONa6Gd pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 53–68°. In the second O2- site, O2- is bonded to six Na1+ and one Gd3+ atom to form distorted ONa6Gd pentagonal bipyramids that share corners with two equivalent ONa5Gd octahedra, edges with four equivalent ONa5Gd octahedra, and edges with five equivalent ONa6Gd pentagonal bipyramids. The corner-sharing octahedral tilt angles are 44°. In the third O2- site, O2- is bonded in a 5-coordinate geometry to four Na1+ and one Gd3+ atom.