Ca3(FeN2)2 crystallizes in the orthorhombic Imm2 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 5-coordinate geometry to one N(2), one N(3), and three equivalent N(1) atoms. In the second Ca site, Ca(2) is bonded in a distorted see-saw-like geometry to two equivalent N(1) and two equivalent N(3) atoms. Fe(1) is bonded in a distorted trigonal planar geometry to one N(1), one N(2), and one N(3) atom. There are three inequivalent N sites. In the first N site, N(1) is bonded to one Ca(2), three equivalent Ca(1), and one Fe(1) atom to form distorted NCa4Fe trigonal bipyramids that share corners with two equivalent N(3)Ca4Fe2 octahedra, corners with seven equivalent N(1)Ca4Fe trigonal bipyramids, and edges with two equivalent N(3)Ca4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 29-40°. In the second N site, N(2) is bonded in a square co-planar geometry to two equivalent Ca(1) and two equivalent Fe(1) atoms. In the third N site, N(3) is bonded to two equivalent Ca(1), two equivalent Ca(2), and two equivalent Fe(1) atoms to form distorted NCa4Fe2 octahedra that share corners with two equivalent N(3)Ca4Fe2 octahedra, corners with four equivalent N(1)Ca4Fe trigonal bipyramids, and edges with four equivalent N(1)Ca4Fe trigonal bipyramids. The corner-sharing octahedral tilt angles are 18°.
Ca3(FeN2)2 crystallizes in the orthorhombic Imm2 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 5-coordinate geometry to one N(2), one N(3), and three equivalent N(1) atoms. The Ca(1)-N(2) bond length is 2.47 Å. The Ca(1)-N(3) bond length is 2.60 Å. There are two shorter (2.48 Å) and one longer (2.68 Å) Ca(1)-N(1) bond length. In the second Ca site, Ca(2) is bonded in a distorted see-saw-like geometry to two equivalent N(1) and two equivalent N(3) atoms. Both Ca(2)-N(1) bond lengths are 2.42 Å. Both Ca(2)-N(3) bond lengths are 2.46 Å. Fe(1) is bonded in a distorted trigonal planar geometry to one N(1), one N(2), and one N(3) atom. The Fe(1)-N(1) bond length is 1.72 Å. The Fe(1)-N(2) bond length is 1.75 Å. The Fe(1)-N(3) bond length is 1.82 Å. There are three inequivalent N sites. In the first N site, N(1) is bonded to one Ca(2), three equivalent Ca(1), and one Fe(1) atom to form distorted NCa4Fe trigonal bipyramids that share corners with two equivalent N(3)Ca4Fe2 octahedra, corners with seven equivalent N(1)Ca4Fe trigonal bipyramids, and edges with two equivalent N(3)Ca4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 29-40°. In the second N site, N(2) is bonded in a square co-planar geometry to two equivalent Ca(1) and two equivalent Fe(1) atoms. In the third N site, N(3) is bonded to two equivalent Ca(1), two equivalent Ca(2), and two equivalent Fe(1) atoms to form distorted NCa4Fe2 octahedra that share corners with two equivalent N(3)Ca4Fe2 octahedra, corners with four equivalent N(1)Ca4Fe trigonal bipyramids, and edges with four equivalent N(1)Ca4Fe trigonal bipyramids. The corner-sharing octahedral tilt angles are 18°.