DOE OSTI2020
Li14Be6(BO3)9 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. there are four inequivalent Li sites. In the first Li site, Li is bonded to four O atoms to form LiO4 tetrahedra that share a cornercorner with one LiO4 tetrahedra, corners with three equivalent BeO4 tetrahedra, and an edgeedge with one LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.97–2.06 Å. In the second Li site, Li is bonded in a trigonal planar geometry to three equivalent O atoms. All Li–O bond lengths are 1.95 Å. In the third Li site, Li is bonded in a 6-coordinate geometry to six equivalent O atoms. All Li–O bond lengths are 2.26 Å. In the fourth Li site, Li is bonded to four O atoms to form distorted LiO4 tetrahedra that share corners with two equivalent LiO4 tetrahedra, corners with four equivalent BeO4 tetrahedra, and an edgeedge with one LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.95–2.03 Å. Be is bonded to four O atoms to form BeO4 tetrahedra that share corners with seven LiO4 tetrahedra. There is two shorter (1.63 Å) and two longer (1.66 Å) Be–O bond length. There are four inequivalent B sites. In the first B site, B is bonded in a trigonal planar geometry to three equivalent O atoms. All B–O bond lengths are 1.39 Å. In the second B site, B is bonded in a trigonal planar geometry to three equivalent O atoms. All B–O bond lengths are 1.38 Å. In the third B site, B is bonded in a trigonal planar geometry to three O atoms. There is one shorter (1.37 Å) and two longer (1.40 Å) B–O bond length. In the fourth B site, B is bonded in a trigonal planar geometry to three equivalent O atoms. All B–O bond lengths are 1.39 Å. There are five inequivalent O sites. In the first O site, O is bonded to two Li, one Be, and one B atom to form a mixture of distorted corner and edge-sharing OLi2BeB tetrahedra. In the second O site, O is bonded to two equivalent Li, one Be, and one B atom to form distorted corner-sharing OLi2BeB tetrahedra. In the third O site, O is bonded in a 4-coordinate geometry to two Li, one Be, and one B atom. In the fourth O site, O is bonded to two Li, one Be, and one B atom to form a mixture of distorted corner and edge-sharing OLi2BeB tetrahedra. In the fifth O site, O is bonded to three Li and one B atom to form corner-sharing OLi3B tetrahedra.