Ni4CN4 crystallizes in the orthorhombic Pnma space group. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a distorted rectangular see-saw-like geometry to one N(1), one N(3), and two equivalent N(2) atoms. In the second Ni site, Ni(2) is bonded in a square co-planar geometry to two equivalent N(2) and two equivalent N(3) atoms. In the third Ni site, Ni(3) is bonded in a rectangular see-saw-like geometry to two equivalent N(1) and two equivalent N(4) atoms. In the fourth Ni site, Ni(4) is bonded in a distorted trigonal planar geometry to one N(2) and two equivalent N(1) atoms. C(1) is bonded in a linear geometry to one N(3) and one N(4) atom. There are four inequivalent N sites. In the first N site, N(4) is bonded in a distorted T-shaped geometry to two equivalent Ni(3) and one C(1) atom. In the second N site, N(1) is bonded to one Ni(1), two equivalent Ni(3), and two equivalent Ni(4) atoms to form distorted NNi5 trigonal bipyramids that share  a cornercorner with one N(3)Ni3C tetrahedra, corners with four equivalent N(2)Ni5 trigonal bipyramids, and edges with two equivalent N(1)Ni5 trigonal bipyramids. In the third N site, N(2) is bonded to one Ni(4), two equivalent Ni(1), and two equivalent Ni(2) atoms to form distorted NNi5 trigonal bipyramids that share corners with four equivalent N(3)Ni3C tetrahedra, corners with four equivalent N(1)Ni5 trigonal bipyramids,  an edgeedge with one N(3)Ni3C tetrahedra, and edges with two equivalent N(2)Ni5 trigonal bipyramids. In the fourth N site, N(3) is bonded to one Ni(1), two equivalent Ni(2), and one C(1) atom to form NNi3C tetrahedra that share corners with two equivalent N(3)Ni3C tetrahedra,  a cornercorner with one N(1)Ni5 trigonal bipyramid, corners with four equivalent N(2)Ni5 trigonal bipyramids, and  an edgeedge with one N(2)Ni5 trigonal bipyramid.
Ni4CN4 crystallizes in the orthorhombic Pnma space group. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a distorted rectangular see-saw-like geometry to one N(1), one N(3), and two equivalent N(2) atoms. The Ni(1)-N(1) bond length is 1.91 Å. The Ni(1)-N(3) bond length is 2.17 Å. Both Ni(1)-N(2) bond lengths are 1.96 Å. In the second Ni site, Ni(2) is bonded in a square co-planar geometry to two equivalent N(2) and two equivalent N(3) atoms. Both Ni(2)-N(2) bond lengths are 1.87 Å. Both Ni(2)-N(3) bond lengths are 1.99 Å. In the third Ni site, Ni(3) is bonded in a rectangular see-saw-like geometry to two equivalent N(1) and two equivalent N(4) atoms. Both Ni(3)-N(1) bond lengths are 1.92 Å. Both Ni(3)-N(4) bond lengths are 1.95 Å. In the fourth Ni site, Ni(4) is bonded in a distorted trigonal planar geometry to one N(2) and two equivalent N(1) atoms. The Ni(4)-N(2) bond length is 1.81 Å. Both Ni(4)-N(1) bond lengths are 1.96 Å. C(1) is bonded in a linear geometry to one N(3) and one N(4) atom. The C(1)-N(3) bond length is 1.25 Å. The C(1)-N(4) bond length is 1.22 Å. There are four inequivalent N sites. In the first N site, N(4) is bonded in a distorted T-shaped geometry to two equivalent Ni(3) and one C(1) atom. In the second N site, N(1) is bonded to one Ni(1), two equivalent Ni(3), and two equivalent Ni(4) atoms to form distorted NNi5 trigonal bipyramids that share  a cornercorner with one N(3)Ni3C tetrahedra, corners with four equivalent N(2)Ni5 trigonal bipyramids, and edges with two equivalent N(1)Ni5 trigonal bipyramids. In the third N site, N(2) is bonded to one Ni(4), two equivalent Ni(1), and two equivalent Ni(2) atoms to form distorted NNi5 trigonal bipyramids that share corners with four equivalent N(3)Ni3C tetrahedra, corners with four equivalent N(1)Ni5 trigonal bipyramids,  an edgeedge with one N(3)Ni3C tetrahedra, and edges with two equivalent N(2)Ni5 trigonal bipyramids. In the fourth N site, N(3) is bonded to one Ni(1), two equivalent Ni(2), and one C(1) atom to form NNi3C tetrahedra that share corners with two equivalent N(3)Ni3C tetrahedra,  a cornercorner with one N(1)Ni5 trigonal bipyramid, corners with four equivalent N(2)Ni5 trigonal bipyramids, and  an edgeedge with one N(2)Ni5 trigonal bipyramid.