DOE OSTI2020
Y2Bi2O7 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 5-coordinate geometry to seven O2- atoms. There are a spread of Y–O bond distances ranging from 2.25–2.90 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 2.21–2.47 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 2.21–2.81 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 2.38–2.88 Å. There are four inequivalent Bi4+ sites. In the first Bi4+ site, Bi4+ is bonded to six O2- atoms to form corner-sharing BiO6 octahedra. The corner-sharing octahedra tilt angles range from 45–54°. There are a spread of Bi–O bond distances ranging from 2.13–2.28 Å. In the second Bi4+ site, Bi4+ is bonded to six O2- atoms to form corner-sharing BiO6 octahedra. The corner-sharing octahedra tilt angles range from 42–56°. There are a spread of Bi–O bond distances ranging from 2.22–2.38 Å. In the third Bi4+ site, Bi4+ is bonded to six O2- atoms to form corner-sharing BiO6 octahedra. The corner-sharing octahedra tilt angles range from 45–62°. There are a spread of Bi–O bond distances ranging from 2.10–2.35 Å. In the fourth Bi4+ site, Bi4+ is bonded to six O2- atoms to form distorted corner-sharing BiO6 octahedra. The corner-sharing octahedra tilt angles range from 34–62°. There are a spread of Bi–O bond distances ranging from 2.20–2.49 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Y3+ and one Bi4+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+ and two Bi4+ atoms. In the third O2- site, O2- is bonded in a trigonal planar geometry to one Y3+ and two Bi4+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Y3+ and two Bi4+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to three Y3+ and one Bi4+ atom. In the sixth O2- site, O2- is bonded to two Y3+ and two equivalent Bi4+ atoms to form distorted corner-sharing OY2Bi2 trigonal pyramids. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+ and two Bi4+ atoms. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Y3+ and one Bi4+ atom. In the ninth O2- site, O2- is bonded to two Y3+ and two Bi4+ atoms to form distorted corner-sharing OY2Bi2 trigonal pyramids. In the tenth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Y3+ and two Bi4+ atoms. In the eleventh O2- site, O2- is bonded in a distorted see-saw-like geometry to two Y3+ and two Bi4+ atoms. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to three Y3+ and one Bi4+ atom. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+ and two equivalent Bi4+ atoms. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+ and two Bi4+ atoms.