Materials Data on U3Sn7 by Materials Project
U3Sn7 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. there are two inequivalent U sites. In the first U site, U is bonded in a 10-coordinate geometry to ten Sn atoms. There are a spread of U–Sn bond distances ranging from 3.20–3.40 Å. In the second U site, U is bonded to twelve Sn atoms to form a mixture of corner and face-sharing USn12 cuboctahedra. There are a spread of U–Sn bond distances ranging from 3.24–3.34 Å. There are four inequivalent Sn sites. In the first Sn site, Sn is bonded in a 4-coordinate geometry to four U atoms. In the second Sn site, Sn is bonded in a 12-coordinate geometry to six equivalent U and two equivalent Sn atoms. Both Sn–Sn bond lengths are 3.10 Å. In the third Sn site, Sn is bonded in a distorted rectangular see-saw-like geometry to four U atoms. In the fourth Sn site, Sn is bonded in a distorted square co-planar geometry to four equivalent U atoms.