DOE OSTI2020
Li3NbO4 is Caswellsilverite-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to six O2- atoms to form LiO6 octahedra that share corners with six equivalent LiO6 octahedra, edges with four NbO6 octahedra, and edges with eight LiO6 octahedra. The corner-sharing octahedra tilt angles range from 0–12°. There are four shorter (2.09 Å) and two longer (2.15 Å) Li–O bond lengths. In the second Li1+ site, Li1+ is bonded to six O2- atoms to form LiO6 octahedra that share corners with two equivalent NbO6 octahedra, corners with four equivalent LiO6 octahedra, edges with four equivalent NbO6 octahedra, and edges with eight equivalent LiO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.08 Å) and two longer (2.36 Å) Li–O bond lengths. There are two inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with two equivalent LiO6 octahedra, corners with four equivalent NbO6 octahedra, and edges with twelve LiO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (1.94 Å) and four longer (2.08 Å) Nb–O bond lengths. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with two equivalent LiO6 octahedra, corners with four equivalent NbO6 octahedra, and edges with twelve LiO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (1.94 Å) and four longer (2.08 Å) Nb–O bond lengths. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to five Li1+ and one Nb5+ atom to form a mixture of corner and edge-sharing OLi5Nb octahedra. The corner-sharing octahedra tilt angles range from 0–12°. In the second O2- site, O2- is bonded to four Li1+ and two equivalent Nb5+ atoms to form OLi4Nb2 octahedra that share corners with six OLi4Nb2 octahedra and edges with twelve OLi5Nb octahedra. The corner-sharing octahedral tilt angles are 0°. Both O–Li bond lengths are 2.15 Å. In the third O2- site, O2- is bonded to four Li1+ and two equivalent Nb5+ atoms to form OLi4Nb2 octahedra that share corners with six OLi4Nb2 octahedra and edges with twelve OLi5Nb octahedra. The corner-sharing octahedral tilt angles are 0°. In the fourth O2- site, O2- is bonded to four Li1+ and two equivalent Nb5+ atoms to form OLi4Nb2 octahedra that share corners with six OLi4Nb2 octahedra and edges with twelve OLi5Nb octahedra. The corner-sharing octahedral tilt angles are 0°. Both O–Li bond lengths are 2.08 Å. In the fifth O2- site, O2- is bonded to four Li1+ and two equivalent Nb5+ atoms to form OLi4Nb2 octahedra that share corners with six OLi4Nb2 octahedra and edges with twelve OLi5Nb octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.08 Å) and two longer (2.15 Å) O–Li bond lengths.