Materials Data on Li4NbCu3O8 by Materials Project
Li4NbCu3O8 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three 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 NbO6 octahedra, edges with six LiO6 octahedra, and edges with six CuO6 octahedra. The corner-sharing octahedra tilt angles range from 6–12°. There are four shorter (2.12 Å) and two longer (2.57 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 six equivalent CuO6 octahedra, edges with two equivalent NbO6 octahedra, edges with four CuO6 octahedra, and edges with six LiO6 octahedra. The corner-sharing octahedra tilt angles range from 3–14°. There are a spread of Li–O bond distances ranging from 2.13–2.19 Å. In the third Li1+ site, Li1+ is bonded to six O2- atoms to form LiO6 octahedra that share corners with six equivalent CuO6 octahedra, edges with two equivalent NbO6 octahedra, edges with four equivalent CuO6 octahedra, and edges with six LiO6 octahedra. The corner-sharing octahedra tilt angles range from 9–12°. There are four shorter (2.06 Å) and two longer (2.54 Å) Li–O bond lengths. Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six equivalent LiO6 octahedra, edges with six LiO6 octahedra, and edges with six CuO6 octahedra. The corner-sharing octahedra tilt angles range from 6–12°. There are four shorter (2.00 Å) and two longer (2.11 Å) Nb–O bond lengths. There are two inequivalent Cu+2.33+ sites. In the first Cu+2.33+ site, Cu+2.33+ is bonded to six O2- atoms to form distorted CuO6 octahedra that share corners with six equivalent LiO6 octahedra, edges with two equivalent NbO6 octahedra, edges with four CuO6 octahedra, and edges with six LiO6 octahedra. The corner-sharing octahedra tilt angles range from 3–14°. There are a spread of Cu–O bond distances ranging from 1.93–2.54 Å. In the second Cu+2.33+ site, Cu+2.33+ is bonded to six O2- atoms to form CuO6 octahedra that share corners with six equivalent LiO6 octahedra, edges with two equivalent NbO6 octahedra, edges with four equivalent CuO6 octahedra, and edges with six LiO6 octahedra. The corner-sharing octahedra tilt angles range from 9–12°. There are four shorter (2.06 Å) and two longer (2.15 Å) Cu–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to three Li1+ and three Cu+2.33+ atoms to form distorted OLi3Cu3 octahedra that share corners with six equivalent OLi3Cu3 octahedra and edges with twelve OLi3NbCu2 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second O2- site, O2- is bonded to three Li1+, one Nb5+, and two Cu+2.33+ atoms to form distorted OLi3NbCu2 octahedra that share corners with six equivalent OLi3NbCu2 octahedra and edges with twelve OLi3Cu3 octahedra. The corner-sharing octahedral tilt angles are 0°. In the third O2- site, O2- is bonded to three Li1+, one Nb5+, and two equivalent Cu+2.33+ atoms to form distorted OLi3NbCu2 octahedra that share corners with six equivalent OLi3NbCu2 octahedra and edges with twelve OLi3Cu3 octahedra. The corner-sharing octahedral tilt angles are 0°.