Zr3TaFe8 is Hexagonal Laves-derived structured and crystallizes in the trigonal R3m space group. There are three inequivalent Zr sites. In the first Zr site, Zr(1) is bonded in a 12-coordinate geometry to one Zr(3), three equivalent Zr(2), three equivalent Fe(1), three equivalent Fe(4), and six equivalent Fe(2) atoms. In the second Zr site, Zr(2) is bonded in a 16-coordinate geometry to three equivalent Zr(1), one Ta(1), three equivalent Fe(2), three equivalent Fe(4), and six equivalent Fe(1) atoms. In the third Zr site, Zr(3) is bonded in a 16-coordinate geometry to one Zr(1), three equivalent Ta(1), three equivalent Fe(1), three equivalent Fe(3), and six equivalent Fe(2) atoms. Ta(1) is bonded in a 16-coordinate geometry to one Zr(2), three equivalent Zr(3), three equivalent Fe(2), three equivalent Fe(3), and six equivalent Fe(1) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one Zr(1), one Zr(3), two equivalent Zr(2), two equivalent Ta(1), one Fe(3), one Fe(4), and four equivalent Fe(1) atoms to form FeZr4Ta2Fe6 cuboctahedra that share corners with two equivalent Fe(3)Zr3Ta3Fe6 cuboctahedra, corners with two equivalent Fe(4)Zr6Fe6 cuboctahedra, corners with four equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra, corners with ten equivalent Fe(2)Zr5TaFe6 cuboctahedra, edges with two equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra, edges with four equivalent Fe(2)Zr5TaFe6 cuboctahedra, faces with three equivalent Fe(3)Zr3Ta3Fe6 cuboctahedra, faces with three equivalent Fe(4)Zr6Fe6 cuboctahedra, faces with four equivalent Fe(2)Zr5TaFe6 cuboctahedra, and faces with eight equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra. In the second Fe site, Fe(2) is bonded to one Zr(2), two equivalent Zr(1), two equivalent Zr(3), one Ta(1), one Fe(3), one Fe(4), and four equivalent Fe(2) atoms to form FeZr5TaFe6 cuboctahedra that share corners with two equivalent Fe(3)Zr3Ta3Fe6 cuboctahedra, corners with two equivalent Fe(4)Zr6Fe6 cuboctahedra, corners with four equivalent Fe(2)Zr5TaFe6 cuboctahedra, corners with ten equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra, edges with two equivalent Fe(2)Zr5TaFe6 cuboctahedra, edges with four equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra, faces with three equivalent Fe(3)Zr3Ta3Fe6 cuboctahedra, faces with three equivalent Fe(4)Zr6Fe6 cuboctahedra, faces with four equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra, and faces with eight equivalent Fe(2)Zr5TaFe6 cuboctahedra. In the third Fe site, Fe(3) is bonded to three equivalent Zr(3), three equivalent Ta(1), three equivalent Fe(1), and three equivalent Fe(2) atoms to form FeZr3Ta3Fe6 cuboctahedra that share corners with six equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra, corners with six equivalent Fe(2)Zr5TaFe6 cuboctahedra, corners with six equivalent Fe(4)Zr6Fe6 cuboctahedra, edges with six equivalent Fe(3)Zr3Ta3Fe6 cuboctahedra, faces with nine equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra, and faces with nine equivalent Fe(2)Zr5TaFe6 cuboctahedra. In the fourth Fe site, Fe(4) is bonded to three equivalent Zr(1), three equivalent Zr(2), three equivalent Fe(1), and three equivalent Fe(2) atoms to form FeZr6Fe6 cuboctahedra that share corners with six equivalent Fe(3)Zr3Ta3Fe6 cuboctahedra, corners with six equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra, corners with six equivalent Fe(2)Zr5TaFe6 cuboctahedra, edges with six equivalent Fe(4)Zr6Fe6 cuboctahedra, faces with nine equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra, and faces with nine equivalent Fe(2)Zr5TaFe6 cuboctahedra.
Zr3TaFe8 is Hexagonal Laves-derived structured and crystallizes in the trigonal R3m space group. There are three inequivalent Zr sites. In the first Zr site, Zr(1) is bonded in a 12-coordinate geometry to one Zr(3), three equivalent Zr(2), three equivalent Fe(1), three equivalent Fe(4), and six equivalent Fe(2) atoms. The Zr(1)-Zr(3) bond length is 3.07 Å. All Zr(1)-Zr(2) bond lengths are 3.05 Å. All Zr(1)-Fe(1) bond lengths are 2.94 Å. All Zr(1)-Fe(4) bond lengths are 2.92 Å. All Zr(1)-Fe(2) bond lengths are 2.93 Å. In the second Zr site, Zr(2) is bonded in a 16-coordinate geometry to three equivalent Zr(1), one Ta(1), three equivalent Fe(2), three equivalent Fe(4), and six equivalent Fe(1) atoms. The Zr(2)-Ta(1) bond length is 3.03 Å. All Zr(2)-Fe(2) bond lengths are 2.96 Å. All Zr(2)-Fe(4) bond lengths are 2.92 Å. All Zr(2)-Fe(1) bond lengths are 2.92 Å. In the third Zr site, Zr(3) is bonded in a 16-coordinate geometry to one Zr(1), three equivalent Ta(1), three equivalent Fe(1), three equivalent Fe(3), and six equivalent Fe(2) atoms. All Zr(3)-Ta(1) bond lengths are 3.04 Å. All Zr(3)-Fe(1) bond lengths are 2.87 Å. All Zr(3)-Fe(3) bond lengths are 2.91 Å. All Zr(3)-Fe(2) bond lengths are 2.91 Å. Ta(1) is bonded in a 16-coordinate geometry to one Zr(2), three equivalent Zr(3), three equivalent Fe(2), three equivalent Fe(3), and six equivalent Fe(1) atoms. All Ta(1)-Fe(2) bond lengths are 2.89 Å. All Ta(1)-Fe(3) bond lengths are 2.91 Å. All Ta(1)-Fe(1) bond lengths are 2.90 Å. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one Zr(1), one Zr(3), two equivalent Zr(2), two equivalent Ta(1), one Fe(3), one Fe(4), and four equivalent Fe(1) atoms to form FeZr4Ta2Fe6 cuboctahedra that share corners with two equivalent Fe(3)Zr3Ta3Fe6 cuboctahedra, corners with two equivalent Fe(4)Zr6Fe6 cuboctahedra, corners with four equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra, corners with ten equivalent Fe(2)Zr5TaFe6 cuboctahedra, edges with two equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra, edges with four equivalent Fe(2)Zr5TaFe6 cuboctahedra, faces with three equivalent Fe(3)Zr3Ta3Fe6 cuboctahedra, faces with three equivalent Fe(4)Zr6Fe6 cuboctahedra, faces with four equivalent Fe(2)Zr5TaFe6 cuboctahedra, and faces with eight equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra. The Fe(1)-Fe(3) bond length is 2.46 Å. The Fe(1)-Fe(4) bond length is 2.51 Å. There are two shorter (2.48 Å) and two longer (2.49 Å) Fe(1)-Fe(1) bond lengths. In the second Fe site, Fe(2) is bonded to one Zr(2), two equivalent Zr(1), two equivalent Zr(3), one Ta(1), one Fe(3), one Fe(4), and four equivalent Fe(2) atoms to form FeZr5TaFe6 cuboctahedra that share corners with two equivalent Fe(3)Zr3Ta3Fe6 cuboctahedra, corners with two equivalent Fe(4)Zr6Fe6 cuboctahedra, corners with four equivalent Fe(2)Zr5TaFe6 cuboctahedra, corners with ten equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra, edges with two equivalent Fe(2)Zr5TaFe6 cuboctahedra, edges with four equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra, faces with three equivalent Fe(3)Zr3Ta3Fe6 cuboctahedra, faces with three equivalent Fe(4)Zr6Fe6 cuboctahedra, faces with four equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra, and faces with eight equivalent Fe(2)Zr5TaFe6 cuboctahedra. The Fe(2)-Fe(3) bond length is 2.47 Å. The Fe(2)-Fe(4) bond length is 2.51 Å. There are two shorter (2.48 Å) and two longer (2.49 Å) Fe(2)-Fe(2) bond lengths. In the third Fe site, Fe(3) is bonded to three equivalent Zr(3), three equivalent Ta(1), three equivalent Fe(1), and three equivalent Fe(2) atoms to form FeZr3Ta3Fe6 cuboctahedra that share corners with six equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra, corners with six equivalent Fe(2)Zr5TaFe6 cuboctahedra, corners with six equivalent Fe(4)Zr6Fe6 cuboctahedra, edges with six equivalent Fe(3)Zr3Ta3Fe6 cuboctahedra, faces with nine equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra, and faces with nine equivalent Fe(2)Zr5TaFe6 cuboctahedra. In the fourth Fe site, Fe(4) is bonded to three equivalent Zr(1), three equivalent Zr(2), three equivalent Fe(1), and three equivalent Fe(2) atoms to form FeZr6Fe6 cuboctahedra that share corners with six equivalent Fe(3)Zr3Ta3Fe6 cuboctahedra, corners with six equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra, corners with six equivalent Fe(2)Zr5TaFe6 cuboctahedra, edges with six equivalent Fe(4)Zr6Fe6 cuboctahedra, faces with nine equivalent Fe(1)Zr4Ta2Fe6 cuboctahedra, and faces with nine equivalent Fe(2)Zr5TaFe6 cuboctahedra.