Materials Data on YUB8 by Materials Project
UYB8 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. U3+ is bonded in a 12-coordinate geometry to eighteen B+0.75- atoms. There are a spread of U–B bond distances ranging from 2.70–2.99 Å. Y3+ is bonded in a 4-coordinate geometry to eighteen B+0.75- atoms. There are a spread of Y–B bond distances ranging from 2.71–3.03 Å. There are five inequivalent B+0.75- sites. In the first B+0.75- site, B+0.75- is bonded in a 9-coordinate geometry to two equivalent U3+, two equivalent Y3+, and five B+0.75- atoms. There are a spread of B–B bond distances ranging from 1.71–1.86 Å. In the second B+0.75- site, B+0.75- is bonded in a 9-coordinate geometry to two equivalent U3+, two equivalent Y3+, and five B+0.75- atoms. There is one shorter (1.69 Å) and two longer (1.75 Å) B–B bond length. In the third B+0.75- site, B+0.75- is bonded in a distorted trigonal planar geometry to two equivalent U3+, four equivalent Y3+, and three B+0.75- atoms. The B–B bond length is 1.78 Å. In the fourth B+0.75- site, B+0.75- is bonded in a distorted trigonal planar geometry to four equivalent U3+, two equivalent Y3+, and three B+0.75- atoms. The B–B bond length is 1.73 Å. In the fifth B+0.75- site, B+0.75- is bonded in a 1-coordinate geometry to two equivalent U3+, two equivalent Y3+, and five B+0.75- atoms. The B–B bond length is 1.60 Å.