DOE OSTI2020
Li8Pb3 crystallizes in the monoclinic C2/m space group. The structure is two-dimensional and consists of one Li8Pb3 sheet oriented in the (0, 0, 1) direction. there are four inequivalent Li sites. In the first Li site, Li is bonded to three equivalent Li and four Pb atoms to form distorted LiLi3Pb4 tetrahedra that share corners with four LiLi3Pb4 tetrahedra, edges with nine LiLi3Pb4 tetrahedra, and faces with three equivalent LiLi4Pb4 tetrahedra. All Li–Li bond lengths are 2.90 Å. There are one shorter (2.86 Å) and three longer (2.92 Å) Li–Pb bond lengths. In the second Li site, Li is bonded in a distorted trigonal non-coplanar geometry to one Li and three equivalent Pb atoms. The Li–Li bond length is 3.04 Å. All Li–Pb bond lengths are 2.98 Å. In the third Li site, Li is bonded to four equivalent Li and four Pb atoms to form a mixture of distorted edge, face, and corner-sharing LiLi4Pb4 tetrahedra. There are one shorter (2.86 Å) and three longer (2.93 Å) Li–Li bond lengths. There are three shorter (2.90 Å) and one longer (2.91 Å) Li–Pb bond lengths. In the fourth Li site, Li is bonded in a 10-coordinate geometry to eight Li and six Pb atoms. There are a spread of Li–Pb bond distances ranging from 3.34–3.37 Å. There are two inequivalent Pb sites. In the first Pb site, Pb is bonded in a 7-coordinate geometry to ten Li atoms. In the second Pb site, Pb is bonded in a body-centered cubic geometry to fourteen Li atoms.