Materials Data on Na2UTeO7 by Materials Project
Na2UTeO7 crystallizes in the orthorhombic Ama2 space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to seven O2- atoms to form distorted NaO7 pentagonal bipyramids that share corners with two equivalent TeO6 octahedra, edges with four equivalent NaO8 hexagonal bipyramids, and edges with two equivalent TeO6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are a spread of Na–O bond distances ranging from 2.37–2.77 Å. In the second Na1+ site, Na1+ is bonded to eight O2- atoms to form distorted NaO8 hexagonal bipyramids that share edges with two equivalent NaO8 hexagonal bipyramids, edges with two equivalent TeO6 octahedra, and edges with four equivalent NaO7 pentagonal bipyramids. There are a spread of Na–O bond distances ranging from 2.47–2.89 Å. U6+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of U–O bond distances ranging from 1.87–2.58 Å. Te6+ is bonded to six O2- atoms to form TeO6 octahedra that share corners with two equivalent TeO6 octahedra, corners with two equivalent NaO7 pentagonal bipyramids, edges with two equivalent NaO8 hexagonal bipyramids, and edges with two equivalent NaO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 33°. There are a spread of Te–O bond distances ranging from 1.92–1.99 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one U6+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one U6+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one U6+, and one Te6+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Na1+, one U6+, and two equivalent Te6+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one U6+, and one Te6+ atom.