Sr2NbN3 crystallizes in the monoclinic C2/c space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one N(1), one N(2), two equivalent N(3), and two equivalent N(4) atoms to form distorted SrN6 pentagonal pyramids that share corners with two equivalent Sr(1)N6 pentagonal pyramids, corners with two equivalent Nb(1)N4 tetrahedra, edges with two equivalent Sr(1)N6 pentagonal pyramids, and edges with three equivalent Nb(1)N4 tetrahedra. In the second Sr site, Sr(2) is bonded in a 6-coordinate geometry to one N(1), one N(2), two equivalent N(3), and two equivalent N(4) atoms. Nb(1) is bonded to one N(1), one N(2), one N(3), and one N(4) atom to form NbN4 tetrahedra that share corners with two equivalent Sr(1)N6 pentagonal pyramids, corners with two equivalent Nb(1)N4 tetrahedra, and edges with three equivalent Sr(1)N6 pentagonal pyramids. There are four inequivalent N sites. In the first N site, N(4) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and one Nb(1) atom. In the second N site, N(1) is bonded in a distorted linear geometry to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Nb(1) atoms. In the third N site, N(2) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Nb(1) atoms. In the fourth N site, N(3) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and one Nb(1) atom.
Sr2NbN3 crystallizes in the monoclinic C2/c space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one N(1), one N(2), two equivalent N(3), and two equivalent N(4) atoms to form distorted SrN6 pentagonal pyramids that share corners with two equivalent Sr(1)N6 pentagonal pyramids, corners with two equivalent Nb(1)N4 tetrahedra, edges with two equivalent Sr(1)N6 pentagonal pyramids, and edges with three equivalent Nb(1)N4 tetrahedra. The Sr(1)-N(1) bond length is 2.86 Å. The Sr(1)-N(2) bond length is 2.80 Å. There is one shorter (2.59 Å) and one longer (2.65 Å) Sr(1)-N(3) bond length. There is one shorter (2.71 Å) and one longer (2.79 Å) Sr(1)-N(4) bond length. In the second Sr site, Sr(2) is bonded in a 6-coordinate geometry to one N(1), one N(2), two equivalent N(3), and two equivalent N(4) atoms. The Sr(2)-N(1) bond length is 2.95 Å. The Sr(2)-N(2) bond length is 3.04 Å. There is one shorter (2.60 Å) and one longer (3.07 Å) Sr(2)-N(3) bond length. There is one shorter (2.62 Å) and one longer (2.65 Å) Sr(2)-N(4) bond length. Nb(1) is bonded to one N(1), one N(2), one N(3), and one N(4) atom to form NbN4 tetrahedra that share corners with two equivalent Sr(1)N6 pentagonal pyramids, corners with two equivalent Nb(1)N4 tetrahedra, and edges with three equivalent Sr(1)N6 pentagonal pyramids. The Nb(1)-N(1) bond length is 2.00 Å. The Nb(1)-N(2) bond length is 2.02 Å. The Nb(1)-N(3) bond length is 1.93 Å. The Nb(1)-N(4) bond length is 1.91 Å. There are four inequivalent N sites. In the first N site, N(4) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and one Nb(1) atom. In the second N site, N(1) is bonded in a distorted linear geometry to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Nb(1) atoms. In the third N site, N(2) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Nb(1) atoms. In the fourth N site, N(3) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and one Nb(1) atom.