DOE OSTI2020
Ta(Cu3O4)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Ta5+ is bonded in a body-centered cubic geometry to eight O2- atoms. All Ta–O bond lengths are 2.15 Å. There are four inequivalent Cu+1.83+ sites. In the first Cu+1.83+ site, Cu+1.83+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.95 Å) and two longer (1.96 Å) Cu–O bond length. In the second Cu+1.83+ site, Cu+1.83+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.95 Å) and two longer (1.96 Å) Cu–O bond length. In the third Cu+1.83+ site, Cu+1.83+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.95 Å) and two longer (1.96 Å) Cu–O bond length. In the fourth Cu+1.83+ site, Cu+1.83+ is bonded in a square co-planar geometry to four equivalent O2- atoms. All Cu–O bond lengths are 1.95 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to one Ta5+ and three Cu+1.83+ atoms to form a mixture of corner and edge-sharing OTaCu3 tetrahedra. In the second O2- site, O2- is bonded to one Ta5+ and three Cu+1.83+ atoms to form a mixture of corner and edge-sharing OTaCu3 tetrahedra. In the third O2- site, O2- is bonded to one Ta5+ and three Cu+1.83+ atoms to form a mixture of corner and edge-sharing OTaCu3 tetrahedra.