Zr3Fe3C crystallizes in the cubic Fd-3m space group. Zr(1) is bonded in a 2-coordinate geometry to two equivalent Fe(1), four equivalent Fe(2), and two equivalent C(1) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to six equivalent Zr(1) and six equivalent Fe(2) atoms to form FeZr6Fe6 cuboctahedra that share corners with six equivalent Fe(2)Zr6Fe6 cuboctahedra, edges with six equivalent C(1)Zr6 octahedra, faces with six equivalent Fe(1)Zr6Fe6 cuboctahedra, and faces with eight equivalent Fe(2)Zr6Fe6 cuboctahedra. In the second Fe site, Fe(2) is bonded to six equivalent Zr(1), three equivalent Fe(1), and three equivalent Fe(2) atoms to form FeZr6Fe6 cuboctahedra that share corners with three equivalent Fe(1)Zr6Fe6 cuboctahedra, corners with six equivalent Fe(2)Zr6Fe6 cuboctahedra, corners with three equivalent C(1)Zr6 octahedra, faces with four equivalent Fe(1)Zr6Fe6 cuboctahedra, faces with nine equivalent Fe(2)Zr6Fe6 cuboctahedra, and faces with three equivalent C(1)Zr6 octahedra. The corner-sharing octahedral tilt angles are 43°. C(1) is bonded to six equivalent Zr(1) atoms to form CZr6 octahedra that share corners with six equivalent Fe(2)Zr6Fe6 cuboctahedra, corners with six equivalent C(1)Zr6 octahedra, edges with six equivalent Fe(1)Zr6Fe6 cuboctahedra, and faces with six equivalent Fe(2)Zr6Fe6 cuboctahedra. The corner-sharing octahedral tilt angles are 47°.
Zr3Fe3C crystallizes in the cubic Fd-3m space group. Zr(1) is bonded in a 2-coordinate geometry to two equivalent Fe(1), four equivalent Fe(2), and two equivalent C(1) atoms. Both Zr(1)-Fe(1) bond lengths are 2.93 Å. There are two shorter (2.95 Å) and two longer (3.00 Å) Zr(1)-Fe(2) bond lengths. Both Zr(1)-C(1) bond lengths are 2.28 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to six equivalent Zr(1) and six equivalent Fe(2) atoms to form FeZr6Fe6 cuboctahedra that share corners with six equivalent Fe(2)Zr6Fe6 cuboctahedra, edges with six equivalent C(1)Zr6 octahedra, faces with six equivalent Fe(1)Zr6Fe6 cuboctahedra, and faces with eight equivalent Fe(2)Zr6Fe6 cuboctahedra. All Fe(1)-Fe(2) bond lengths are 2.49 Å. In the second Fe site, Fe(2) is bonded to six equivalent Zr(1), three equivalent Fe(1), and three equivalent Fe(2) atoms to form FeZr6Fe6 cuboctahedra that share corners with three equivalent Fe(1)Zr6Fe6 cuboctahedra, corners with six equivalent Fe(2)Zr6Fe6 cuboctahedra, corners with three equivalent C(1)Zr6 octahedra, faces with four equivalent Fe(1)Zr6Fe6 cuboctahedra, faces with nine equivalent Fe(2)Zr6Fe6 cuboctahedra, and faces with three equivalent C(1)Zr6 octahedra. The corner-sharing octahedral tilt angles are 43°. All Fe(2)-Fe(2) bond lengths are 2.38 Å. C(1) is bonded to six equivalent Zr(1) atoms to form CZr6 octahedra that share corners with six equivalent Fe(2)Zr6Fe6 cuboctahedra, corners with six equivalent C(1)Zr6 octahedra, edges with six equivalent Fe(1)Zr6Fe6 cuboctahedra, and faces with six equivalent Fe(2)Zr6Fe6 cuboctahedra. The corner-sharing octahedral tilt angles are 47°.