NaTa3N5 crystallizes in the orthorhombic Cmcm space group. Na(1) is bonded in a 7-coordinate geometry to one N(3), two equivalent N(1), and four equivalent N(2) atoms. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one N(3), two equivalent N(2), and three equivalent N(1) atoms to form a mixture of distorted corner and edge-sharing TaN6 octahedra. The corner-sharing octahedral tilt angles range from 17-58°. In the second Ta site, Ta(2) is bonded to two equivalent N(1), two equivalent N(2), and two equivalent N(3) atoms to form a mixture of distorted corner and edge-sharing TaN6 octahedra. The corner-sharing octahedral tilt angles range from 17-25°. There are three inequivalent N sites. In the first N site, N(1) is bonded to one Na(1), one Ta(2), and three equivalent Ta(1) atoms to form NNaTa4 trigonal bipyramids that share corners with two equivalent N(1)NaTa4 trigonal bipyramids, corners with two equivalent N(3)NaTa4 trigonal bipyramids, corners with six equivalent N(2)Na2Ta3 trigonal bipyramids, edges with two equivalent N(3)NaTa4 trigonal bipyramids, edges with three equivalent N(2)Na2Ta3 trigonal bipyramids, and edges with three equivalent N(1)NaTa4 trigonal bipyramids. In the second N site, N(2) is bonded to two equivalent Na(1), one Ta(2), and two equivalent Ta(1) atoms to form NNa2Ta3 trigonal bipyramids that share corners with two equivalent N(3)NaTa4 trigonal bipyramids, corners with four equivalent N(2)Na2Ta3 trigonal bipyramids, corners with six equivalent N(1)NaTa4 trigonal bipyramids,  an edgeedge with one N(2)Na2Ta3 trigonal bipyramid, edges with two equivalent N(3)NaTa4 trigonal bipyramids, edges with three equivalent N(1)NaTa4 trigonal bipyramids, and  a faceface with one N(2)Na2Ta3 trigonal bipyramid. In the third N site, N(3) is bonded to one Na(1), two equivalent Ta(1), and two equivalent Ta(2) atoms to form distorted NNaTa4 trigonal bipyramids that share corners with two equivalent N(3)NaTa4 trigonal bipyramids, corners with four equivalent N(2)Na2Ta3 trigonal bipyramids, corners with four equivalent N(1)NaTa4 trigonal bipyramids, edges with four equivalent N(2)Na2Ta3 trigonal bipyramids, and edges with four equivalent N(1)NaTa4 trigonal bipyramids.
NaTa3N5 crystallizes in the orthorhombic Cmcm space group. Na(1) is bonded in a 7-coordinate geometry to one N(3), two equivalent N(1), and four equivalent N(2) atoms. The Na(1)-N(3) bond length is 2.57 Å. Both Na(1)-N(1) bond lengths are 2.53 Å. All Na(1)-N(2) bond lengths are 2.48 Å. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one N(3), two equivalent N(2), and three equivalent N(1) atoms to form a mixture of distorted corner and edge-sharing TaN6 octahedra. The corner-sharing octahedral tilt angles range from 17-58°. The Ta(1)-N(3) bond length is 2.42 Å. There is one shorter (2.00 Å) and one longer (2.05 Å) Ta(1)-N(2) bond length. There are two shorter (2.09 Å) and one longer (2.27 Å) Ta(1)-N(1) bond length. In the second Ta site, Ta(2) is bonded to two equivalent N(1), two equivalent N(2), and two equivalent N(3) atoms to form a mixture of distorted corner and edge-sharing TaN6 octahedra. The corner-sharing octahedral tilt angles range from 17-25°. Both Ta(2)-N(1) bond lengths are 2.15 Å. Both Ta(2)-N(2) bond lengths are 2.10 Å. Both Ta(2)-N(3) bond lengths are 2.07 Å. There are three inequivalent N sites. In the first N site, N(1) is bonded to one Na(1), one Ta(2), and three equivalent Ta(1) atoms to form NNaTa4 trigonal bipyramids that share corners with two equivalent N(1)NaTa4 trigonal bipyramids, corners with two equivalent N(3)NaTa4 trigonal bipyramids, corners with six equivalent N(2)Na2Ta3 trigonal bipyramids, edges with two equivalent N(3)NaTa4 trigonal bipyramids, edges with three equivalent N(2)Na2Ta3 trigonal bipyramids, and edges with three equivalent N(1)NaTa4 trigonal bipyramids. In the second N site, N(2) is bonded to two equivalent Na(1), one Ta(2), and two equivalent Ta(1) atoms to form NNa2Ta3 trigonal bipyramids that share corners with two equivalent N(3)NaTa4 trigonal bipyramids, corners with four equivalent N(2)Na2Ta3 trigonal bipyramids, corners with six equivalent N(1)NaTa4 trigonal bipyramids,  an edgeedge with one N(2)Na2Ta3 trigonal bipyramid, edges with two equivalent N(3)NaTa4 trigonal bipyramids, edges with three equivalent N(1)NaTa4 trigonal bipyramids, and  a faceface with one N(2)Na2Ta3 trigonal bipyramid. In the third N site, N(3) is bonded to one Na(1), two equivalent Ta(1), and two equivalent Ta(2) atoms to form distorted NNaTa4 trigonal bipyramids that share corners with two equivalent N(3)NaTa4 trigonal bipyramids, corners with four equivalent N(2)Na2Ta3 trigonal bipyramids, corners with four equivalent N(1)NaTa4 trigonal bipyramids, edges with four equivalent N(2)Na2Ta3 trigonal bipyramids, and edges with four equivalent N(1)NaTa4 trigonal bipyramids.