Materials Data on UMnFe by Materials Project
UMnFe crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. U is bonded in a 12-coordinate geometry to four equivalent U, six equivalent Mn, and six equivalent Fe atoms. All U–U bond lengths are 3.04 Å. All U–Mn bond lengths are 2.91 Å. There are two shorter (2.88 Å) and four longer (2.94 Å) U–Fe bond lengths. Mn is bonded to six equivalent U, two equivalent Mn, and four equivalent Fe atoms to form distorted MnU6Mn2Fe4 cuboctahedra that share corners with eight equivalent FeU6Mn4Fe2 cuboctahedra, corners with ten equivalent MnU6Mn2Fe4 cuboctahedra, edges with six equivalent MnU6Mn2Fe4 cuboctahedra, faces with six equivalent MnU6Mn2Fe4 cuboctahedra, and faces with twelve equivalent FeU6Mn4Fe2 cuboctahedra. Both Mn–Mn bond lengths are 2.51 Å. All Mn–Fe bond lengths are 2.48 Å. Fe is bonded to six equivalent U, four equivalent Mn, and two equivalent Fe atoms to form FeU6Mn4Fe2 cuboctahedra that share corners with eight equivalent MnU6Mn2Fe4 cuboctahedra, corners with ten equivalent FeU6Mn4Fe2 cuboctahedra, edges with six equivalent FeU6Mn4Fe2 cuboctahedra, faces with six equivalent FeU6Mn4Fe2 cuboctahedra, and faces with twelve equivalent MnU6Mn2Fe4 cuboctahedra. Both Fe–Fe bond lengths are 2.48 Å.