Sr3(NiN2)2 crystallizes in the orthorhombic Pnna space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 4-coordinate geometry to one N(1) and three equivalent N(2) atoms. In the second Sr site, Sr(2) is bonded in a 6-coordinate geometry to two equivalent N(2) and four equivalent N(1) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form distorted edge-sharing NiN4 tetrahedra. In the second Ni site, Ni(2) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form distorted edge-sharing NiN4 trigonal pyramids. There are two inequivalent N sites. In the first N site, N(1) is bonded in a 5-coordinate geometry to one Sr(1), two equivalent Sr(2), one Ni(1), and one Ni(2) atom. In the second N site, N(2) is bonded to one Sr(2), three equivalent Sr(1), one Ni(1), and one Ni(2) atom to form a mixture of distorted edge, corner, and face-sharing NSr4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 51-64°.
Sr3(NiN2)2 crystallizes in the orthorhombic Pnna space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 4-coordinate geometry to one N(1) and three equivalent N(2) atoms. The Sr(1)-N(1) bond length is 2.46 Å. There are a spread of Sr(1)-N(2) bond distances ranging from 2.57-2.67 Å. In the second Sr site, Sr(2) is bonded in a 6-coordinate geometry to two equivalent N(2) and four equivalent N(1) atoms. Both Sr(2)-N(2) bond lengths are 2.80 Å. All Sr(2)-N(1) bond lengths are 2.69 Å. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form distorted edge-sharing NiN4 tetrahedra. Both Ni(1)-N(1) bond lengths are 1.86 Å. Both Ni(1)-N(2) bond lengths are 1.93 Å. In the second Ni site, Ni(2) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form distorted edge-sharing NiN4 trigonal pyramids. Both Ni(2)-N(1) bond lengths are 2.01 Å. Both Ni(2)-N(2) bond lengths are 1.92 Å. There are two inequivalent N sites. In the first N site, N(1) is bonded in a 5-coordinate geometry to one Sr(1), two equivalent Sr(2), one Ni(1), and one Ni(2) atom. In the second N site, N(2) is bonded to one Sr(2), three equivalent Sr(1), one Ni(1), and one Ni(2) atom to form a mixture of distorted edge, corner, and face-sharing NSr4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 51-64°.