Materials Data on NaCr4O12 by Materials Project

Abstract

NaCr4O12 crystallizes in the tetragonal I4_1/a space group. The structure is three-dimensional. Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.50–2.59 Å. There are two inequivalent Cr+5.75+ sites. In the first Cr+5.75+ site, Cr+5.75+ is bonded to four O2- atoms to form corner-sharing CrO4 tetrahedra. There are a spread of Cr–O bond distances ranging from 1.60–1.78 Å. In the second Cr+5.75+ site, Cr+5.75+ is bonded to four O2- atoms to form corner-sharing CrO4 tetrahedra. There are a spread of Cr–O bond distances ranging from 1.61–1.83 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Na1+ and one Cr+5.75+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Na1+ and one Cr+5.75+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to two Cr+5.75+ atoms. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Na1+ and one Cr+5.75+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to one Na1+ and one Cr+5.75+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Cr+5.75+ atoms. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Cr+5.75+ atoms.