Fe5CoN4 is pyrite-derived structured and crystallizes in the orthorhombic Pmmn space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 3-coordinate geometry to two equivalent N(1) and two equivalent N(2) atoms. In the second Fe site, Fe(2) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form FeN4 tetrahedra that share corners with four equivalent Co(1)N4 tetrahedra. Co(1) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form CoN4 tetrahedra that share corners with four equivalent Fe(2)N4 tetrahedra. There are two inequivalent N sites. In the first N site, N(1) is bonded in a 6-coordinate geometry to one Fe(2), four equivalent Fe(1), and one Co(1) atom. In the second N site, N(2) is bonded to one Fe(2), four equivalent Fe(1), and one Co(1) atom to form a mixture of corner and edge-sharing NFe5Co octahedra. The corner-sharing octahedral tilt angles range from 56-62°.
Fe5CoN4 is pyrite-derived structured and crystallizes in the orthorhombic Pmmn space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 3-coordinate geometry to two equivalent N(1) and two equivalent N(2) atoms. There is one shorter (1.84 Å) and one longer (2.34 Å) Fe(1)-N(1) bond length. There is one shorter (1.88 Å) and one longer (1.89 Å) Fe(1)-N(2) bond length. In the second Fe site, Fe(2) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form FeN4 tetrahedra that share corners with four equivalent Co(1)N4 tetrahedra. Both Fe(2)-N(1) bond lengths are 1.88 Å. Both Fe(2)-N(2) bond lengths are 1.92 Å. Co(1) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form CoN4 tetrahedra that share corners with four equivalent Fe(2)N4 tetrahedra. Both Co(1)-N(1) bond lengths are 1.91 Å. Both Co(1)-N(2) bond lengths are 2.01 Å. There are two inequivalent N sites. In the first N site, N(1) is bonded in a 6-coordinate geometry to one Fe(2), four equivalent Fe(1), and one Co(1) atom. In the second N site, N(2) is bonded to one Fe(2), four equivalent Fe(1), and one Co(1) atom to form a mixture of corner and edge-sharing NFe5Co octahedra. The corner-sharing octahedral tilt angles range from 56-62°.