Materials Data on U2(Fe7B2)3 by Materials Project
U2Fe21B6 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. U is bonded in a distorted tetrahedral geometry to four equivalent Fe atoms. All U–Fe bond lengths are 2.44 Å. There are three inequivalent Fe sites. In the first Fe site, Fe is bonded in a distorted bent 150 degrees geometry to one Fe and two equivalent B atoms. The Fe–Fe bond length is 2.55 Å. Both Fe–B bond lengths are 2.12 Å. In the second Fe site, Fe is bonded to one U and three equivalent B atoms to form a mixture of edge and corner-sharing FeUB3 tetrahedra. All Fe–B bond lengths are 2.14 Å. In the third Fe site, Fe is bonded in a cuboctahedral geometry to twelve equivalent Fe atoms. B is bonded in a 8-coordinate geometry to eight Fe atoms.
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