Fe2Nb is Hexagonal Laves-like structured and crystallizes in the hexagonal P6_3/mmc space group. There are five inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 16-coordinate geometry to one Nb(1), three equivalent Nb(2), three equivalent Fe(1), three equivalent Fe(3), and six equivalent Fe(2) atoms. In the second Nb site, Nb(1) is bonded in a 16-coordinate geometry to one Nb(1), three equivalent Nb(2), three equivalent Fe(1), three equivalent Fe(3), and six equivalent Fe(2) atoms. In the third Nb site, Nb(1) is bonded in a 16-coordinate geometry to one Nb(1), three equivalent Nb(2), three equivalent Fe(1), three equivalent Fe(3), and six equivalent Fe(2) atoms. In the fourth Nb site, Nb(2) is bonded in a 16-coordinate geometry to one Nb(2), three equivalent Nb(1), three equivalent Fe(1), three equivalent Fe(2), and six equivalent Fe(3) atoms. In the fifth Nb site, Nb(2) is bonded in a 16-coordinate geometry to one Nb(2), three equivalent Nb(1), three equivalent Fe(1), three equivalent Fe(2), and six equivalent Fe(3) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to three equivalent Nb(1), three equivalent Nb(2), three equivalent Fe(2), and three equivalent Fe(3) atoms to form a mixture of edge, face, and corner-sharing FeNb6Fe6 cuboctahedra. In the second Fe site, Fe(2) is bonded to two equivalent Nb(2); four Nb(1,1); two equivalent Fe(1); and four equivalent Fe(2) atoms to form a mixture of edge, face, and corner-sharing FeNb6Fe6 cuboctahedra. In the third Fe site, Fe(3) is bonded to two Nb(1,1); four Nb(2,2); two equivalent Fe(1); and four equivalent Fe(3) atoms to form a mixture of edge, face, and corner-sharing FeNb6Fe6 cuboctahedra.
Fe2Nb is Hexagonal Laves-like structured and crystallizes in the hexagonal P6_3/mmc space group. There are five inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 16-coordinate geometry to one Nb(1), three equivalent Nb(2), three equivalent Fe(1), three equivalent Fe(3), and six equivalent Fe(2) atoms. The Nb(1)-Nb(1) bond length is 2.88 Å. All Nb(1)-Nb(2) bond lengths are 2.93 Å. All Nb(1)-Fe(1) bond lengths are 2.81 Å. All Nb(1)-Fe(3) bond lengths are 2.80 Å. All Nb(1)-Fe(2) bond lengths are 2.79 Å. In the second Nb site, Nb(1) is bonded in a 16-coordinate geometry to one Nb(1), three equivalent Nb(2), three equivalent Fe(1), three equivalent Fe(3), and six equivalent Fe(2) atoms. All Nb(1)-Nb(2) bond lengths are 2.93 Å. All Nb(1)-Fe(1) bond lengths are 2.81 Å. All Nb(1)-Fe(3) bond lengths are 2.80 Å. All Nb(1)-Fe(2) bond lengths are 2.79 Å. In the third Nb site, Nb(1) is bonded in a 16-coordinate geometry to one Nb(1), three equivalent Nb(2), three equivalent Fe(1), three equivalent Fe(3), and six equivalent Fe(2) atoms. The Nb(1)-Nb(1) bond length is 2.88 Å. All Nb(1)-Nb(2) bond lengths are 2.93 Å. All Nb(1)-Fe(1) bond lengths are 2.81 Å. All Nb(1)-Fe(3) bond lengths are 2.80 Å. All Nb(1)-Fe(2) bond lengths are 2.79 Å. In the fourth Nb site, Nb(2) is bonded in a 16-coordinate geometry to one Nb(2), three equivalent Nb(1), three equivalent Fe(1), three equivalent Fe(2), and six equivalent Fe(3) atoms. The Nb(2)-Nb(2) bond length is 2.93 Å. All Nb(2)-Fe(1) bond lengths are 2.80 Å. All Nb(2)-Fe(2) bond lengths are 2.80 Å. All Nb(2)-Fe(3) bond lengths are 2.81 Å. In the fifth Nb site, Nb(2) is bonded in a 16-coordinate geometry to one Nb(2), three equivalent Nb(1), three equivalent Fe(1), three equivalent Fe(2), and six equivalent Fe(3) atoms. The Nb(2)-Nb(2) bond length is 2.93 Å. All Nb(2)-Fe(1) bond lengths are 2.80 Å. All Nb(2)-Fe(2) bond lengths are 2.80 Å. All Nb(2)-Fe(3) bond lengths are 2.81 Å. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to three equivalent Nb(1), three equivalent Nb(2), three equivalent Fe(2), and three equivalent Fe(3) atoms to form a mixture of edge, face, and corner-sharing FeNb6Fe6 cuboctahedra. All Fe(1)-Fe(2) bond lengths are 2.41 Å. All Fe(1)-Fe(3) bond lengths are 2.39 Å. In the second Fe site, Fe(2) is bonded to two equivalent Nb(2); four Nb(1,1); two equivalent Fe(1); and four equivalent Fe(2) atoms to form a mixture of edge, face, and corner-sharing FeNb6Fe6 cuboctahedra. All Fe(2)-Fe(2) bond lengths are 2.39 Å. In the third Fe site, Fe(3) is bonded to two Nb(1,1); four Nb(2,2); two equivalent Fe(1); and four equivalent Fe(3) atoms to form a mixture of edge, face, and corner-sharing FeNb6Fe6 cuboctahedra. There are two shorter (2.33 Å) and two longer (2.45 Å) Fe(3)-Fe(3) bond lengths.