Materials Data on Al2NiO4 by Materials Project
NiAl2O4 is Spinel-like structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are six inequivalent Ni2+ sites. In the first Ni2+ site, Ni2+ is bonded to four O2- atoms to form NiO4 tetrahedra that share corners with three NiO6 octahedra and corners with nine AlO6 octahedra. The corner-sharing octahedra tilt angles range from 56–65°. There are a spread of Ni–O bond distances ranging from 1.94–1.99 Å. In the second Ni2+ site, Ni2+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with six AlO4 tetrahedra, edges with two NiO6 octahedra, and edges with four AlO6 octahedra. There are a spread of Ni–O bond distances ranging from 2.04–2.09 Å. In the third Ni2+ site, Ni2+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with two equivalent NiO4 tetrahedra, corners with four AlO4 tetrahedra, an edgeedge with one NiO6 octahedra, and edges with five AlO6 octahedra. There are a spread of Ni–O bond distances ranging from 2.02–2.08 Å. In the fourth Ni2+ site, Ni2+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with six AlO4 tetrahedra, edges with two NiO6 octahedra, and edges with four AlO6 octahedra. There are a spread of Ni–O bond distances ranging from 2.04–2.10 Å. In the fifth Ni2+ site, Ni2+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with six AlO4 tetrahedra, edges with two NiO6 octahedra, and edges with four equivalent AlO6 octahedra. There are a spread of Ni–O bond distances ranging from 2.04–2.07 Å. In the sixth Ni2+ site, Ni2+ is bonded to six O2- atoms to form NiO6 octahedra that share a cornercorner with one NiO4 tetrahedra, corners with five AlO4 tetrahedra, an edgeedge with one NiO6 octahedra, and edges with five AlO6 octahedra. There are a spread of Ni–O bond distances ranging from 2.02–2.07 Å. There are nine inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with two equivalent NiO4 tetrahedra, corners with four AlO4 tetrahedra, edges with three NiO6 octahedra, and edges with three AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.87–1.98 Å. In the second Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with three equivalent NiO4 tetrahedra, corners with three equivalent AlO4 tetrahedra, edges with two NiO6 octahedra, and edges with four AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.86–2.00 Å. In the third Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with six NiO6 octahedra and corners with six AlO6 octahedra. The corner-sharing octahedra tilt angles range from 53–59°. There is three shorter (1.80 Å) and one longer (1.84 Å) Al–O bond length. In the fourth Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six AlO4 tetrahedra, edges with two equivalent AlO6 octahedra, and edges with four NiO6 octahedra. There are a spread of Al–O bond distances ranging from 1.89–1.98 Å. In the fifth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with six NiO6 octahedra and corners with six AlO6 octahedra. The corner-sharing octahedra tilt angles range from 51–58°. There is two shorter (1.78 Å) and two longer (1.82 Å) Al–O bond length. In the sixth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with six NiO6 octahedra and corners with six AlO6 octahedra. The corner-sharing octahedra tilt angles range from 53–59°. There are a spread of Al–O bond distances ranging from 1.79–1.85 Å. In the seventh Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one NiO4 tetrahedra, corners with five AlO4 tetrahedra, edges with three NiO6 octahedra, and edges with three AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.86–2.02 Å. In the eighth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with six NiO6 octahedra and corners with six AlO6 octahedra. The corner-sharing octahedra tilt angles range from 53–59°. There are a spread of Al–O bond distances ranging from 1.79–1.85 Å. In the ninth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with three NiO6 octahedra and corners with nine AlO6 octahedra. The corner-sharing octahedra tilt angles range from 56–59°. There are a spread of Al–O bond distances ranging from 1.80–1.91 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Ni2+ and two Al3+ atoms. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ni2+ and three Al3+ atoms. In the third O2- site, O2- is bonded to one Ni2+ and three Al3+ atoms to form distorted corner-sharing OAl3Ni trigonal pyramids. In the fourth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ni2+ and three Al3+ atoms. In the fifth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Ni2+ and two Al3+ atoms. In the sixth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Ni2+ and two Al3+ atoms. In the seventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ni2+ and three Al3+ atoms. In the eighth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ni2+ and three Al3+ atoms. In the ninth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ni2+ and three Al3+ atoms. In the tenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Ni2+ and two Al3+ atoms. In the eleventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ni2+ and three Al3+ atoms. In the twelfth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Ni2+ and two Al3+ atoms. In the thirteenth O2- site, O2- is bonded to two Ni2+ and two equivalent Al3+ atoms to form distorted corner-sharing OAl2Ni2 trigonal pyramids. In the fourteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ni2+ and three Al3+ atoms. In the fifteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ni2+ and three Al3+ atoms. In the sixteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to four Al3+ atoms. In the seventeenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ni2+ and three Al3+ atoms. In the eighteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ni2+ and three Al3+ atoms.