Materials Data on U3Si11Pt23 by Materials Project
U3Pt23Si11 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. U+3.33+ is bonded in a 8-coordinate geometry to four equivalent U+3.33+ and four equivalent Pt2- atoms. All U–U bond lengths are 2.82 Å. All U–Pt bond lengths are 3.08 Å. There are four inequivalent Pt2- sites. In the first Pt2- site, Pt2- is bonded in a 3-coordinate geometry to one U+3.33+, two equivalent Pt2-, and three Si+3.27+ atoms. Both Pt–Pt bond lengths are 3.19 Å. There are a spread of Pt–Si bond distances ranging from 2.43–2.48 Å. In the second Pt2- site, Pt2- is bonded to four Si+3.27+ atoms to form a mixture of distorted edge and corner-sharing PtSi4 tetrahedra. There are one shorter (2.28 Å) and three longer (2.51 Å) Pt–Si bond lengths. In the third Pt2- site, Pt2- is bonded in a body-centered cubic geometry to eight equivalent Pt2- atoms. In the fourth Pt2- site, Pt2- is bonded to four Si+3.27+ atoms to form a mixture of edge and corner-sharing PtSi4 tetrahedra. There are one shorter (2.45 Å) and three longer (2.49 Å) Pt–Si bond lengths. There are three inequivalent Si+3.27+ sites. In the first Si+3.27+ site, Si+3.27+ is bonded in a distorted tetrahedral geometry to four Pt2- atoms. In the second Si+3.27+ site, Si+3.27+ is bonded in a body-centered cubic geometry to eight Pt2- atoms. In the third Si+3.27+ site, Si+3.27+ is bonded in a 7-coordinate geometry to seven Pt2- atoms.