Materials Data on Na4AlFe3O8 by Materials Project

Abstract

Na4Fe3AlO8 is beta beryllia-derived structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share corners with two equivalent AlO4 tetrahedra, corners with four NaO4 tetrahedra, and corners with six FeO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.30–2.37 Å. In the second Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share corners with two equivalent AlO4 tetrahedra, corners with four NaO4 tetrahedra, and corners with six FeO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.34–2.43 Å. In the third Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share corners with two equivalent AlO4 tetrahedra, corners with four NaO4 tetrahedra, and corners with six FeO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.31–2.40 Å. In the fourth Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share corners with two equivalent AlO4 tetrahedra, corners with four NaO4 tetrahedra, and corners with six FeO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.30–2.37 Å. There are three inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with two equivalent FeO4 tetrahedra, corners with two equivalent AlO4 tetrahedra, and corners with eight NaO4 tetrahedra. There is one shorter (1.90 Å) and three longer (1.91 Å) Fe–O bond length. In the second Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with four FeO4 tetrahedra and corners with eight NaO4 tetrahedra. There is one shorter (1.90 Å) and three longer (1.91 Å) Fe–O bond length. In the third Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with two equivalent FeO4 tetrahedra, corners with two equivalent AlO4 tetrahedra, and corners with eight NaO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.89–1.92 Å. Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with four FeO4 tetrahedra and corners with eight NaO4 tetrahedra. There is two shorter (1.78 Å) and two longer (1.79 Å) Al–O bond length. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Fe3+, and one Al3+ atom. In the second O2- site, O2- is bonded to two Na1+ and two Fe3+ atoms to form distorted ONa2Fe2 tetrahedra that share corners with six ONa2Fe2 tetrahedra and corners with four ONa2AlFe trigonal pyramids. In the third O2- site, O2- is bonded to two Na1+ and two Fe3+ atoms to form distorted ONa2Fe2 tetrahedra that share corners with eight ONa2Fe2 tetrahedra and corners with four ONa2AlFe trigonal pyramids. In the fourth O2- site, O2- is bonded to two Na1+, one Fe3+, and one Al3+ atom to form distorted ONa2AlFe tetrahedra that share corners with six ONa2Fe2 tetrahedra and corners with four ONa2AlFe trigonal pyramids. In the fifth O2- site, O2- is bonded to two Na1+ and two Fe3+ atoms to form ONa2Fe2 tetrahedra that share corners with eight ONa2Fe2 tetrahedra and corners with two equivalent ONa2AlFe trigonal pyramids. In the sixth O2- site, O2- is bonded to two Na1+ and two Fe3+ atoms to form distorted ONa2Fe2 tetrahedra that share corners with eight ONa2Fe2 tetrahedra and corners with two equivalent ONa2AlFe trigonal pyramids. In the seventh O2- site, O2- is bonded to two Na1+, one Fe3+, and one Al3+ atom to form distorted ONa2AlFe trigonal pyramids that share corners with eight ONa2Fe2 tetrahedra and corners with two equivalent ONa2AlFe trigonal pyramids. In the eighth O2- site, O2- is bonded to two Na1+, one Fe3+, and one Al3+ atom to form distorted ONa2AlFe trigonal pyramids that share corners with eight ONa2Fe2 tetrahedra and corners with two equivalent ONa2AlFe trigonal pyramids.