Materials Data on NaTi3Nb(CuO4)3 by Materials Project

Abstract

NaCu3Ti3NbO12 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share faces with two equivalent NbO6 octahedra and faces with six equivalent TiO6 octahedra. There are six shorter (2.66 Å) and six longer (2.67 Å) Na–O bond lengths. Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent NbO6 octahedra, corners with four equivalent TiO6 octahedra, and faces with two equivalent NaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 40°. There are a spread of Ti–O bond distances ranging from 1.98–2.00 Å. Nb5+ is bonded to six equivalent O2- atoms to form NbO6 octahedra that share corners with six equivalent TiO6 octahedra and faces with two equivalent NaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 40°. All Nb–O bond lengths are 2.01 Å. Cu2+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.97 Å) and two longer (1.98 Å) Cu–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, two equivalent Ti4+, and one Cu2+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Ti4+, one Nb5+, and one Cu2+ atom.