Materials Data on Na3Fe2Mo5O16 by Materials Project
Na3Fe2Mo5O16 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 1-coordinate geometry to four O2- atoms. There are one shorter (2.20 Å) and three longer (2.49 Å) Na–O bond lengths. In the second Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six equivalent O2- atoms. All Na–O bond lengths are 2.60 Å. In the third Na1+ site, Na1+ is bonded in a 1-coordinate geometry to four O2- atoms. There are one shorter (2.27 Å) and three longer (2.49 Å) Na–O bond lengths. In the fourth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six equivalent O2- atoms. All Na–O bond lengths are 2.62 Å. There are three inequivalent Mo+4.60+ sites. In the first Mo+4.60+ site, Mo+4.60+ is bonded to four O2- atoms to form MoO4 tetrahedra that share corners with three equivalent FeO6 octahedra. The corner-sharing octahedral tilt angles are 21°. There is one shorter (1.76 Å) and three longer (1.82 Å) Mo–O bond length. In the second Mo+4.60+ site, Mo+4.60+ is bonded to six O2- atoms to form MoO6 octahedra that share corners with four FeO6 octahedra and edges with four equivalent MoO6 octahedra. The corner-sharing octahedra tilt angles range from 52–53°. There are a spread of Mo–O bond distances ranging from 2.02–2.13 Å. In the third Mo+4.60+ site, Mo+4.60+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Mo–O bond distances ranging from 1.76–2.49 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six equivalent MoO6 octahedra and corners with three equivalent MoO4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. There are three shorter (2.16 Å) and three longer (2.21 Å) Fe–O bond lengths. In the second Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six equivalent MoO6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are three shorter (2.04 Å) and three longer (2.15 Å) Fe–O bond lengths. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to four Mo+4.60+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to three equivalent Mo+4.60+ atoms. In the third O2- site, O2- is bonded in a linear geometry to one Na1+ and one Mo+4.60+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Mo+4.60+, and one Fe3+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Mo+4.60+, and one Fe3+ atom. In the sixth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Na1+, two equivalent Mo+4.60+, and one Fe3+ atom. In the seventh O2- site, O2- is bonded to one Na1+, two equivalent Mo+4.60+, and one Fe3+ atom to form a mixture of distorted corner and edge-sharing ONaFeMo2 trigonal pyramids. In the eighth O2- site, O2- is bonded in a linear geometry to one Na1+ and one Mo+4.60+ atom.