DOI: 10.17188/1306919
title: Materials Data on Na5LaO4 by Materials Project

description: Na5LaO4 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 NaO4 tetrahedra that share corners with six NaO4 tetrahedra, corners with four equivalent LaO4 trigonal pyramids, and edges with five NaO4 tetrahedra. There are two shorter (2.27 Å) and two longer (2.48 Å) Na–O bond lengths. In the second Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with ten NaO4 tetrahedra, corners with two equivalent LaO4 trigonal pyramids, edges with four NaO4 tetrahedra, and an edgeedge with one LaO4 trigonal pyramid. There are a spread of Na–O bond distances ranging from 2.28–2.52 Å. In the third Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share corners with ten NaO4 tetrahedra, corners with four equivalent LaO4 trigonal pyramids, and edges with two NaO4 tetrahedra. All Na–O bond lengths are 2.40 Å. In the fourth Na1+ site, Na1+ is bonded to four equivalent O2- atoms to form NaO4 tetrahedra that share corners with eight equivalent NaO4 tetrahedra, corners with four equivalent LaO4 trigonal pyramids, and edges with six NaO4 tetrahedra. There are two shorter (2.38 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 eight equivalent NaO4 tetrahedra, corners with four equivalent LaO4 trigonal pyramids, and edges with two equivalent NaO4 tetrahedra. All Na–O bond lengths are 2.37 Å. In the sixth Na1+ site, Na1+ is bonded to four equivalent O2- atoms to form NaO4 tetrahedra that share corners with four equivalent LaO4 trigonal pyramids and edges with six NaO4 tetrahedra. All Na–O bond lengths are 2.37 Å. La3+ is bonded to four O2- atoms to form LaO4 trigonal pyramids that share corners with sixteen NaO4 tetrahedra and edges with two equivalent NaO4 tetrahedra. There are a spread of La–O bond distances ranging from 2.28–2.41 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to five Na1+ and one La3+ atom to form distorted ONa5La octahedra that share corners with two equivalent ONa5La octahedra, a cornercorner with one ONa6La pentagonal bipyramid, corners with three equivalent ONa4La trigonal bipyramids, edges with four equivalent ONa5La octahedra, and edges with two equivalent ONa6La pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 55–67°. In the second O2- site, O2- is bonded to six Na1+ and one La3+ atom to form distorted ONa6La pentagonal bipyramids that share corners with two equivalent ONa5La octahedra, a cornercorner with one ONa4La trigonal bipyramid, edges with four equivalent ONa5La octahedra, and edges with five equivalent ONa6La pentagonal bipyramids. The corner-sharing octahedral tilt angles are 46°. In the third O2- site, O2- is bonded to four Na1+ and one La3+ atom to form distorted ONa4La trigonal bipyramids that share corners with six equivalent ONa5La octahedra, a cornercorner with one ONa6La pentagonal bipyramid, corners with two equivalent ONa4La trigonal bipyramids, and edges with three equivalent ONa4La trigonal bipyramids. The corner-sharing octahedra tilt angles range from 61–70°.