DOE OSTI2020
NaNbO3 is (Cubic) Perovskite-like structured and crystallizes in the orthorhombic P222_1 space group. The structure is three-dimensional. there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with twelve NaO12 cuboctahedra, faces with six NaO12 cuboctahedra, and faces with eight NbO6 octahedra. There are a spread of Na–O bond distances ranging from 2.75–2.93 Å. In the second Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with twelve NaO12 cuboctahedra, faces with six NaO12 cuboctahedra, and faces with eight NbO6 octahedra. There are a spread of Na–O bond distances ranging from 2.79–2.88 Å. In the third Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with twelve NaO12 cuboctahedra, faces with six NaO12 cuboctahedra, and faces with eight NbO6 octahedra. There are a spread of Na–O bond distances ranging from 2.72–2.96 Å. In the fourth Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with twelve NaO12 cuboctahedra, faces with six NaO12 cuboctahedra, and faces with eight NbO6 octahedra. There are a spread of Na–O bond distances ranging from 2.75–2.95 Å. 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 six NbO6 octahedra and faces with eight NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 2–8°. There are a spread of Nb–O bond distances ranging from 1.90–2.13 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six NbO6 octahedra and faces with eight NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 3–12°. There are a spread of Nb–O bond distances ranging from 1.92–2.11 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to four Na1+ and two equivalent Nb5+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four Na1+ and two equivalent Nb5+ atoms. In the third O2- site, O2- is bonded in a distorted linear geometry to four Na1+ and two equivalent Nb5+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to four Na1+ and two equivalent Nb5+ atoms. In the fifth O2- site, O2- is bonded in a distorted linear geometry to four Na1+ and two Nb5+ atoms. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to four Na1+ and two Nb5+ atoms. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to four Na1+ and two Nb5+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to four Na1+ and two Nb5+ atoms.