Materials Data on Sr3Zr2O7 by Materials Project
Sr3Zr2O7 crystallizes in the orthorhombic Pmmm space group. The structure is three-dimensional. there are four inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with four equivalent SrO12 cuboctahedra, faces with four equivalent SrO12 cuboctahedra, and faces with eight equivalent ZrO6 octahedra. All Sr–O bond lengths are 2.96 Å. In the second Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with four equivalent SrO12 cuboctahedra, faces with four equivalent SrO12 cuboctahedra, and faces with eight equivalent ZrO6 octahedra. There are eight shorter (2.95 Å) and four longer (2.96 Å) Sr–O bond lengths. In the third Sr2+ site, Sr2+ is bonded in a 1-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.40–2.98 Å. In the fourth Sr2+ site, Sr2+ is bonded in a 1-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.41–2.98 Å. There are two inequivalent Zr4+ sites. In the first Zr4+ site, Zr4+ is bonded to six O2- atoms to form ZrO6 octahedra that share corners with five equivalent ZrO6 octahedra and faces with four equivalent SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are five shorter (2.10 Å) and one longer (2.12 Å) Zr–O bond lengths. In the second Zr4+ site, Zr4+ is bonded to six O2- atoms to form ZrO6 octahedra that share corners with five equivalent ZrO6 octahedra and faces with four equivalent SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are five shorter (2.10 Å) and one longer (2.13 Å) Zr–O bond lengths. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to four Sr2+ and two equivalent Zr4+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four Sr2+ and two equivalent Zr4+ atoms. In the third O2- site, O2- is bonded in a distorted linear geometry to four Sr2+ and two equivalent Zr4+ atoms. In the fourth O2- site, O2- is bonded in a distorted linear geometry to five Sr2+ and one Zr4+ atom. In the fifth O2- site, O2- is bonded in a distorted linear geometry to four equivalent Sr2+ and two equivalent Zr4+ atoms. In the sixth O2- site, O2- is bonded in a distorted linear geometry to four equivalent Sr2+ and two equivalent Zr4+ atoms. In the seventh O2- site, O2- is bonded in a distorted linear geometry to five Sr2+ and one Zr4+ atom.