Materials Data on BaNa6O4 by Materials Project

Abstract

Na6BaO4 crystallizes in the cubic I-43m space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share a cornercorner with one BaO4 tetrahedra, corners with twelve NaO4 tetrahedra, an edgeedge with one BaO4 tetrahedra, and edges with five equivalent NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.28–2.60 Å. In the second Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with three equivalent BaO4 tetrahedra, corners with twelve NaO4 tetrahedra, and edges with five equivalent NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.43–2.71 Å. Ba2+ is bonded to four O2- atoms to form BaO4 tetrahedra that share corners with three equivalent BaO4 tetrahedra, corners with twelve NaO4 tetrahedra, and edges with three equivalent NaO4 tetrahedra. There are one shorter (2.51 Å) and three longer (2.54 Å) Ba–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to six Na1+ and one Ba2+ atom to form distorted OBaNa6 pentagonal bipyramids that share corners with two equivalent OBaNa6 pentagonal bipyramids, a cornercorner with one OBa4 tetrahedra, and edges with six equivalent OBaNa6 pentagonal bipyramids. In the second O2- site, O2- is bonded to four equivalent Ba2+ atoms to form corner-sharing OBa4 tetrahedra. In the third O2- site, O2- is bonded in a distorted body-centered cubic geometry to eight Na1+ atoms.