Materials Data on CaEu2B2O7 by Materials Project
CaEu2B2O7 crystallizes in the trigonal R3c space group. The structure is three-dimensional. Ca2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ca–O bond distances ranging from 2.36–2.88 Å. There are two inequivalent Eu3+ sites. In the first Eu3+ site, Eu3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Eu–O bond distances ranging from 2.31–2.63 Å. In the second Eu3+ site, Eu3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Eu–O bond distances ranging from 2.28–2.83 Å. There are six inequivalent B3+ sites. In the first B3+ site, B3+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All B–O bond lengths are 1.39 Å. In the second B3+ site, B3+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All B–O bond lengths are 1.38 Å. In the third B3+ site, B3+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All B–O bond lengths are 1.38 Å. In the fourth B3+ site, B3+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All B–O bond lengths are 1.38 Å. In the fifth B3+ site, B3+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All B–O bond lengths are 1.39 Å. In the sixth B3+ site, B3+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All B–O bond lengths are 1.39 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Ca2+, one Eu3+, and one B3+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Ca2+, three Eu3+, and one B3+ atom. In the third O2- site, O2- is bonded to one Ca2+ and three Eu3+ atoms to form distorted corner-sharing OCaEu3 trigonal pyramids. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to three Eu3+ and one B3+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to one Ca2+, three Eu3+, and one B3+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Ca2+, two Eu3+, and one B3+ atom. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Ca2+, two Eu3+, and one B3+ atom.