Materials Data on Li7Si2 by Materials Project
Li7Si2 is zeta silver zinc-like structured and crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. there are eight inequivalent Li sites. In the first Li site, Li is bonded in a 4-coordinate geometry to two equivalent Li and four equivalent Si atoms. Both Li–Li bond lengths are 2.95 Å. All Li–Si bond lengths are 2.57 Å. In the second Li site, Li is bonded in a body-centered cubic geometry to eight Li atoms. There are two shorter (2.36 Å) and six longer (2.65 Å) Li–Li bond lengths. In the third Li site, Li is bonded in a 3-coordinate geometry to five Li and three Si atoms. There are a spread of Li–Li bond distances ranging from 2.38–2.78 Å. There are one shorter (2.53 Å) and two longer (2.66 Å) Li–Si bond lengths. In the fourth Li site, Li is bonded in a 10-coordinate geometry to two Li and four Si atoms. The Li–Li bond length is 2.73 Å. There are a spread of Li–Si bond distances ranging from 2.70–2.91 Å. In the fifth Li site, Li is bonded in a 3-coordinate geometry to seven Li and three Si atoms. There are two shorter (2.70 Å) and two longer (2.88 Å) Li–Li bond lengths. There are one shorter (2.67 Å) and two longer (2.73 Å) Li–Si bond lengths. In the sixth Li site, Li is bonded in a 2-coordinate geometry to three Li and four Si atoms. The Li–Li bond length is 2.49 Å. There are a spread of Li–Si bond distances ranging from 2.65–2.97 Å. In the seventh Li site, Li is bonded in a 2-coordinate geometry to four Li and two equivalent Si atoms. There are one shorter (2.61 Å) and one longer (2.62 Å) Li–Li bond lengths. There are one shorter (2.69 Å) and one longer (2.72 Å) Li–Si bond lengths. In the eighth Li site, Li is bonded in a 12-coordinate geometry to eight Li and four Si atoms. There are a spread of Li–Si bond distances ranging from 2.82–2.96 Å. There are two inequivalent Si sites. In the first Si site, Si is bonded in a 12-coordinate geometry to twelve Li atoms. In the second Si site, Si is bonded in a 11-coordinate geometry to ten Li and one Si atom. The Si–Si bond length is 2.51 Å.