DOE OSTI2020
Y2Zr2O7 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are four inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Y–O bond distances ranging from 2.23–2.66 Å. In the second Y3+ site, Y3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Y–O bond distances ranging from 2.25–2.47 Å. In the third Y3+ site, Y3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Y–O bond distances ranging from 2.28–2.63 Å. In the fourth Y3+ site, Y3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Y–O bond distances ranging from 2.29–2.95 Å. There are four inequivalent Zr4+ sites. In the first Zr4+ site, Zr4+ is bonded to six O2- atoms to form corner-sharing ZrO6 octahedra. The corner-sharing octahedra tilt angles range from 41–48°. There are a spread of Zr–O bond distances ranging from 2.03–2.19 Å. In the second Zr4+ site, Zr4+ is bonded to six O2- atoms to form corner-sharing ZrO6 octahedra. The corner-sharing octahedra tilt angles range from 34–48°. There are a spread of Zr–O bond distances ranging from 2.00–2.31 Å. In the third Zr4+ site, Zr4+ is bonded to six O2- atoms to form corner-sharing ZrO6 octahedra. The corner-sharing octahedra tilt angles range from 41–53°. There are a spread of Zr–O bond distances ranging from 1.99–2.26 Å. In the fourth Zr4+ site, Zr4+ is bonded to six O2- atoms to form distorted corner-sharing ZrO6 octahedra. The corner-sharing octahedra tilt angles range from 32–53°. There are a spread of Zr–O bond distances ranging from 2.00–2.42 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded to three Y3+ and one Zr4+ atom to form distorted corner-sharing OY3Zr tetrahedra. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+ and two Zr4+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Y3+ and two Zr4+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Y3+ and two Zr4+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to three Y3+ and one Zr4+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+ and two equivalent Zr4+ atoms. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to two Y3+ and two Zr4+ atoms. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Y3+ and one Zr4+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+ and two Zr4+ atoms. In the tenth O2- site, O2- is bonded in a distorted tetrahedral geometry to two Y3+ and two Zr4+ atoms. In the eleventh O2- site, O2- is bonded in a distorted see-saw-like geometry to two Y3+ and two Zr4+ atoms. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to three Y3+ and one Zr4+ atom. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+ and two equivalent Zr4+ atoms. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Y3+ and two Zr4+ atoms.