Fe3Nb is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. Nb(1) is bonded to four equivalent Fe(1) and eight equivalent Fe(2) atoms to form NbFe12 cuboctahedra that share corners with four equivalent Nb(1)Fe12 cuboctahedra, edges with eight equivalent Nb(1)Fe12 cuboctahedra, edges with sixteen equivalent Fe(2)Nb4Fe8 cuboctahedra, faces with four equivalent Nb(1)Fe12 cuboctahedra, and faces with eight equivalent Fe(2)Nb4Fe8 cuboctahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a distorted square co-planar geometry to four equivalent Nb(1) and eight equivalent Fe(2) atoms. In the second Fe site, Fe(2) is bonded to four equivalent Nb(1), four equivalent Fe(1), and four equivalent Fe(2) atoms to form FeNb4Fe8 cuboctahedra that share corners with twelve equivalent Fe(2)Nb4Fe8 cuboctahedra, edges with eight equivalent Nb(1)Fe12 cuboctahedra, edges with eight equivalent Fe(2)Nb4Fe8 cuboctahedra, faces with four equivalent Nb(1)Fe12 cuboctahedra, and faces with ten equivalent Fe(2)Nb4Fe8 cuboctahedra.
Fe3Nb is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. Nb(1) is bonded to four equivalent Fe(1) and eight equivalent Fe(2) atoms to form NbFe12 cuboctahedra that share corners with four equivalent Nb(1)Fe12 cuboctahedra, edges with eight equivalent Nb(1)Fe12 cuboctahedra, edges with sixteen equivalent Fe(2)Nb4Fe8 cuboctahedra, faces with four equivalent Nb(1)Fe12 cuboctahedra, and faces with eight equivalent Fe(2)Nb4Fe8 cuboctahedra. All Nb(1)-Fe(1) bond lengths are 2.53 Å. All Nb(1)-Fe(2) bond lengths are 2.74 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a distorted square co-planar geometry to four equivalent Nb(1) and eight equivalent Fe(2) atoms. All Fe(1)-Fe(2) bond lengths are 2.74 Å. In the second Fe site, Fe(2) is bonded to four equivalent Nb(1), four equivalent Fe(1), and four equivalent Fe(2) atoms to form FeNb4Fe8 cuboctahedra that share corners with twelve equivalent Fe(2)Nb4Fe8 cuboctahedra, edges with eight equivalent Nb(1)Fe12 cuboctahedra, edges with eight equivalent Fe(2)Nb4Fe8 cuboctahedra, faces with four equivalent Nb(1)Fe12 cuboctahedra, and faces with ten equivalent Fe(2)Nb4Fe8 cuboctahedra. All Fe(2)-Fe(2) bond lengths are 2.53 Å.