Ca11(VN5)2 crystallizes in the tetragonal P4_2/mnm space group. There are four inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to two equivalent N(4) and four equivalent N(1) atoms to form CaN6 octahedra that share edges with two equivalent Ca(1)N6 octahedra and edges with eight equivalent Ca(2)N5 trigonal bipyramids. In the second Ca site, Ca(2) is bonded to one N(1), two equivalent N(2), and two equivalent N(4) atoms to form distorted CaN5 trigonal bipyramids that share corners with three equivalent Ca(2)N5 trigonal bipyramids, edges with two equivalent Ca(1)N6 octahedra, and edges with three equivalent Ca(2)N5 trigonal bipyramids. In the third Ca site, Ca(3) is bonded in a rectangular see-saw-like geometry to two equivalent N(1) and two equivalent N(3) atoms. In the fourth Ca site, Ca(4) is bonded in a 4-coordinate geometry to one N(3) and three equivalent N(2) atoms. V(1) is bonded in a linear geometry to one N(3) and one N(4) atom. There are four inequivalent N sites. In the first N site, N(3) is bonded to two equivalent Ca(3), two equivalent Ca(4), and one V(1) atom to form distorted NCa4V trigonal bipyramids that share  a cornercorner with one N(4)Ca5V octahedra, corners with two equivalent N(1)Ca6 octahedra, corners with two equivalent N(3)Ca4V trigonal bipyramids, corners with six equivalent N(2)Ca5 trigonal bipyramids, and  an edgeedge with one N(1)Ca6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the second N site, N(4) is bonded to one Ca(1), four equivalent Ca(2), and one V(1) atom to form NCa5V octahedra that share  a cornercorner with one N(4)Ca5V octahedra,  a cornercorner with one N(3)Ca4V trigonal bipyramid, corners with four equivalent N(2)Ca5 trigonal bipyramids, edges with two equivalent N(4)Ca5V octahedra, edges with four equivalent N(1)Ca6 octahedra, and edges with two equivalent N(2)Ca5 trigonal bipyramids. The corner-sharing octahedra are not tilted. In the third N site, N(1) is bonded to two equivalent Ca(1), two equivalent Ca(2), and two equivalent Ca(3) atoms to form NCa6 octahedra that share corners with two equivalent N(1)Ca6 octahedra, corners with two equivalent N(3)Ca4V trigonal bipyramids, corners with four equivalent N(2)Ca5 trigonal bipyramids, edges with three equivalent N(1)Ca6 octahedra, edges with four equivalent N(4)Ca5V octahedra, and  an edgeedge with one N(3)Ca4V trigonal bipyramid. The corner-sharing octahedra are not tilted. In the fourth N site, N(2) is bonded to two equivalent Ca(2) and three equivalent Ca(4) atoms to form distorted NCa5 trigonal bipyramids that share corners with two equivalent N(4)Ca5V octahedra, corners with two equivalent N(1)Ca6 octahedra, corners with three equivalent N(3)Ca4V trigonal bipyramids, corners with four equivalent N(2)Ca5 trigonal bipyramids,  an edgeedge with one N(4)Ca5V octahedra, and edges with two equivalent N(2)Ca5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 22-68°.
Ca11(VN5)2 crystallizes in the tetragonal P4_2/mnm space group. There are four inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to two equivalent N(4) and four equivalent N(1) atoms to form CaN6 octahedra that share edges with two equivalent Ca(1)N6 octahedra and edges with eight equivalent Ca(2)N5 trigonal bipyramids. Both Ca(1)-N(4) bond lengths are 2.45 Å. All Ca(1)-N(1) bond lengths are 2.50 Å. In the second Ca site, Ca(2) is bonded to one N(1), two equivalent N(2), and two equivalent N(4) atoms to form distorted CaN5 trigonal bipyramids that share corners with three equivalent Ca(2)N5 trigonal bipyramids, edges with two equivalent Ca(1)N6 octahedra, and edges with three equivalent Ca(2)N5 trigonal bipyramids. The Ca(2)-N(1) bond length is 2.42 Å. Both Ca(2)-N(2) bond lengths are 2.55 Å. Both Ca(2)-N(4) bond lengths are 2.56 Å. In the third Ca site, Ca(3) is bonded in a rectangular see-saw-like geometry to two equivalent N(1) and two equivalent N(3) atoms. Both Ca(3)-N(1) bond lengths are 2.42 Å. Both Ca(3)-N(3) bond lengths are 2.28 Å. In the fourth Ca site, Ca(4) is bonded in a 4-coordinate geometry to one N(3) and three equivalent N(2) atoms. The Ca(4)-N(3) bond length is 2.99 Å. There are two shorter (2.43 Å) and one longer (2.47 Å) Ca(4)-N(2) bond length. V(1) is bonded in a linear geometry to one N(3) and one N(4) atom. The V(1)-N(3) bond length is 1.76 Å. The V(1)-N(4) bond length is 1.79 Å. There are four inequivalent N sites. In the first N site, N(3) is bonded to two equivalent Ca(3), two equivalent Ca(4), and one V(1) atom to form distorted NCa4V trigonal bipyramids that share  a cornercorner with one N(4)Ca5V octahedra, corners with two equivalent N(1)Ca6 octahedra, corners with two equivalent N(3)Ca4V trigonal bipyramids, corners with six equivalent N(2)Ca5 trigonal bipyramids, and  an edgeedge with one N(1)Ca6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the second N site, N(4) is bonded to one Ca(1), four equivalent Ca(2), and one V(1) atom to form NCa5V octahedra that share  a cornercorner with one N(4)Ca5V octahedra,  a cornercorner with one N(3)Ca4V trigonal bipyramid, corners with four equivalent N(2)Ca5 trigonal bipyramids, edges with two equivalent N(4)Ca5V octahedra, edges with four equivalent N(1)Ca6 octahedra, and edges with two equivalent N(2)Ca5 trigonal bipyramids. The corner-sharing octahedra are not tilted. In the third N site, N(1) is bonded to two equivalent Ca(1), two equivalent Ca(2), and two equivalent Ca(3) atoms to form NCa6 octahedra that share corners with two equivalent N(1)Ca6 octahedra, corners with two equivalent N(3)Ca4V trigonal bipyramids, corners with four equivalent N(2)Ca5 trigonal bipyramids, edges with three equivalent N(1)Ca6 octahedra, edges with four equivalent N(4)Ca5V octahedra, and  an edgeedge with one N(3)Ca4V trigonal bipyramid. The corner-sharing octahedra are not tilted. In the fourth N site, N(2) is bonded to two equivalent Ca(2) and three equivalent Ca(4) atoms to form distorted NCa5 trigonal bipyramids that share corners with two equivalent N(4)Ca5V octahedra, corners with two equivalent N(1)Ca6 octahedra, corners with three equivalent N(3)Ca4V trigonal bipyramids, corners with four equivalent N(2)Ca5 trigonal bipyramids,  an edgeedge with one N(4)Ca5V octahedra, and edges with two equivalent N(2)Ca5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 22-68°.