Sr3(TaN2)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 5-coordinate geometry to two equivalent 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 Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form distorted edge-sharing TaN4 tetrahedra. In the second Ta site, Ta(2) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form distorted edge-sharing TaN4 tetrahedra. There are two inequivalent N sites. In the first N site, N(1) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), one Ta(1), and one Ta(2) atom. In the second N site, N(2) is bonded to one Sr(2), three equivalent Sr(1), one Ta(1), and one Ta(2) atom to form a mixture of distorted face, corner, and edge-sharing NSr4Ta2 octahedra. The corner-sharing octahedral tilt angles range from 36-66°.
Sr3(TaN2)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 5-coordinate geometry to two equivalent N(1) and three equivalent N(2) atoms. There is one shorter (2.79 Å) and one longer (3.15 Å) Sr(1)-N(1) bond length. There are two shorter (2.68 Å) and one longer (2.80 Å) Sr(1)-N(2) bond length. 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 2.96 Å. There are two shorter (2.83 Å) and two longer (3.16 Å) Sr(2)-N(1) bond lengths. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form distorted edge-sharing TaN4 tetrahedra. Both Ta(1)-N(1) bond lengths are 2.02 Å. Both Ta(1)-N(2) bond lengths are 2.02 Å. In the second Ta site, Ta(2) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form distorted edge-sharing TaN4 tetrahedra. Both Ta(2)-N(1) bond lengths are 2.05 Å. Both Ta(2)-N(2) bond lengths are 2.14 Å. There are two inequivalent N sites. In the first N site, N(1) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), one Ta(1), and one Ta(2) atom. In the second N site, N(2) is bonded to one Sr(2), three equivalent Sr(1), one Ta(1), and one Ta(2) atom to form a mixture of distorted face, corner, and edge-sharing NSr4Ta2 octahedra. The corner-sharing octahedral tilt angles range from 36-66°.