Materials Data on Ca3Zr2O7 by Materials Project
Ca3Zr2O7 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Ca–O bond distances ranging from 2.22–2.45 Å. In the second Ca2+ site, Ca2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are one shorter (2.36 Å) and four longer (2.47 Å) Ca–O bond lengths. Zr4+ is bonded to six O2- atoms to form corner-sharing ZrO6 octahedra. The corner-sharing octahedra tilt angles range from 28–37°. There are a spread of Zr–O bond distances ranging from 2.09–2.15 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted see-saw-like geometry to two equivalent Ca2+ and two equivalent Zr4+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ca2+ and one Zr4+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ca2+ and two equivalent Zr4+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+ and two equivalent Zr4+ atoms.