Sr3CaCN4 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 6-coordinate geometry to one C(1), one N(1), two equivalent N(2), and two equivalent N(4) atoms. In the second Sr site, Sr(2) is bonded in a 5-coordinate geometry to one N(3), two equivalent N(2), and two equivalent N(4) atoms. In the third Sr site, Sr(3) is bonded to one N(4), two equivalent N(1), and three equivalent N(3) atoms to form SrN6 octahedra that share corners with three equivalent Ca(1)N4 trigonal pyramids, edges with four equivalent Sr(3)N6 octahedra, and edges with three equivalent Ca(1)N4 trigonal pyramids. Ca(1) is bonded to one N(1), one N(4), and two equivalent N(3) atoms to form CaN4 trigonal pyramids that share corners with three equivalent Sr(3)N6 octahedra, corners with two equivalent Ca(1)N4 trigonal pyramids, and edges with three equivalent Sr(3)N6 octahedra. The corner-sharing octahedral tilt angles range from 7-9°. C(1) is bonded in a linear geometry to one Sr(1), one N(1), and one N(2) atom. There are four inequivalent N sites. In the first N site, N(4) is bonded to one Sr(3), two equivalent Sr(1), two equivalent Sr(2), and one Ca(1) atom to form NSr5Ca octahedra that share corners with three equivalent N(3)Sr4Ca2 octahedra, edges with two equivalent N(3)Sr4Ca2 octahedra, and edges with two equivalent N(4)Sr5Ca octahedra. The corner-sharing octahedral tilt angles range from 8-55°. In the second N site, N(1) is bonded in a 5-coordinate geometry to one Sr(1), two equivalent Sr(3), one Ca(1), and one C(1) atom. In the third N site, N(2) is bonded in a distorted single-bond geometry to two equivalent Sr(1), two equivalent Sr(2), and one C(1) atom. In the fourth N site, N(3) is bonded to one Sr(2), three equivalent Sr(3), and two equivalent Ca(1) atoms to form NSr4Ca2 octahedra that share corners with three equivalent N(4)Sr5Ca octahedra, edges with two equivalent N(4)Sr5Ca octahedra, and edges with four equivalent N(3)Sr4Ca2 octahedra. The corner-sharing octahedral tilt angles range from 8-55°.
Sr3CaCN4 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 6-coordinate geometry to one C(1), one N(1), two equivalent N(2), and two equivalent N(4) atoms. The Sr(1)-C(1) bond length is 2.91 Å. The Sr(1)-N(1) bond length is 2.77 Å. Both Sr(1)-N(2) bond lengths are 2.81 Å. Both Sr(1)-N(4) bond lengths are 2.54 Å. In the second Sr site, Sr(2) is bonded in a 5-coordinate geometry to one N(3), two equivalent N(2), and two equivalent N(4) atoms. The Sr(2)-N(3) bond length is 2.53 Å. Both Sr(2)-N(2) bond lengths are 2.89 Å. Both Sr(2)-N(4) bond lengths are 2.59 Å. In the third Sr site, Sr(3) is bonded to one N(4), two equivalent N(1), and three equivalent N(3) atoms to form SrN6 octahedra that share corners with three equivalent Ca(1)N4 trigonal pyramids, edges with four equivalent Sr(3)N6 octahedra, and edges with three equivalent Ca(1)N4 trigonal pyramids. The Sr(3)-N(4) bond length is 2.85 Å. Both Sr(3)-N(1) bond lengths are 2.81 Å. There are two shorter (2.70 Å) and one longer (2.71 Å) Sr(3)-N(3) bond length. Ca(1) is bonded to one N(1), one N(4), and two equivalent N(3) atoms to form CaN4 trigonal pyramids that share corners with three equivalent Sr(3)N6 octahedra, corners with two equivalent Ca(1)N4 trigonal pyramids, and edges with three equivalent Sr(3)N6 octahedra. The corner-sharing octahedral tilt angles range from 7-9°. The Ca(1)-N(1) bond length is 2.59 Å. The Ca(1)-N(4) bond length is 2.49 Å. Both Ca(1)-N(3) bond lengths are 2.41 Å. C(1) is bonded in a linear geometry to one Sr(1), one N(1), and one N(2) atom. The C(1)-N(1) bond length is 1.24 Å. The C(1)-N(2) bond length is 1.25 Å. There are four inequivalent N sites. In the first N site, N(4) is bonded to one Sr(3), two equivalent Sr(1), two equivalent Sr(2), and one Ca(1) atom to form NSr5Ca octahedra that share corners with three equivalent N(3)Sr4Ca2 octahedra, edges with two equivalent N(3)Sr4Ca2 octahedra, and edges with two equivalent N(4)Sr5Ca octahedra. The corner-sharing octahedral tilt angles range from 8-55°. In the second N site, N(1) is bonded in a 5-coordinate geometry to one Sr(1), two equivalent Sr(3), one Ca(1), and one C(1) atom. In the third N site, N(2) is bonded in a distorted single-bond geometry to two equivalent Sr(1), two equivalent Sr(2), and one C(1) atom. In the fourth N site, N(3) is bonded to one Sr(2), three equivalent Sr(3), and two equivalent Ca(1) atoms to form NSr4Ca2 octahedra that share corners with three equivalent N(4)Sr5Ca octahedra, edges with two equivalent N(4)Sr5Ca octahedra, and edges with four equivalent N(3)Sr4Ca2 octahedra. The corner-sharing octahedral tilt angles range from 8-55°.