CaHf8(N2O)4 crystallizes in the triclinic P1 space group. Ca(1) is bonded to one N(1), one N(3), one N(4), one N(7), one O(2), and one O(4) atom to form CaN4O2 octahedra that share corners with three equivalent Hf(2)N4O2 octahedra, corners with three equivalent Hf(6)N4O2 octahedra,  a faceface with one Hf(1)N4O2 octahedra, and  a faceface with one Hf(8)N4O2 octahedra. The corner-sharing octahedral tilt angles range from 38-49°. There are eight inequivalent Hf sites. In the first Hf site, Hf(1) is bonded to one N(1), one N(2), one N(4), one N(6), one O(1), and one O(2) atom to form distorted HfN4O2 octahedra that share edges with three equivalent Hf(6)N4O2 octahedra and  a faceface with one Ca(1)N4O2 octahedra. In the second Hf site, Hf(2) is bonded to one N(3), one N(5), one N(7), one N(8), one O(3), and one O(4) atom to form distorted HfN4O2 octahedra that share corners with three equivalent Ca(1)N4O2 octahedra and edges with three equivalent Hf(8)N4O2 octahedra. The corner-sharing octahedral tilt angles range from 38-49°. In the third Hf site, Hf(3) is bonded in a 6-coordinate geometry to one N(2), one N(5), one N(6), one N(8), one O(1), and one O(3) atom. In the fourth Hf site, Hf(4) is bonded in a 6-coordinate geometry to one N(1), one N(3), one N(4), one N(7), one O(2), and one O(4) atom. In the fifth Hf site, Hf(5) is bonded in a 6-coordinate geometry to one N(1), one N(3), one N(4), one N(7), one O(2), and one O(4) atom. In the sixth Hf site, Hf(6) is bonded to one N(1), one N(2), one N(4), one N(6), one O(1), and one O(2) atom to form HfN4O2 octahedra that share corners with three equivalent Ca(1)N4O2 octahedra and edges with three equivalent Hf(1)N4O2 octahedra. The corner-sharing octahedral tilt angles range from 39-48°. In the seventh Hf site, Hf(7) is bonded in a 6-coordinate geometry to one N(2), one N(5), one N(6), one N(8), one O(1), and one O(3) atom. In the eighth Hf site, Hf(8) is bonded to one N(3), one N(5), one N(7), one N(8), one O(3), and one O(4) atom to form distorted HfN4O2 octahedra that share edges with three equivalent Hf(2)N4O2 octahedra and  a faceface with one Ca(1)N4O2 octahedra. There are eight inequivalent N sites. In the first N site, N(1) is bonded to one Ca(1), one Hf(1), one Hf(4), one Hf(5), and one Hf(6) atom to form distorted NCaHf4 trigonal bipyramids that share  a cornercorner with one N(3)CaHf4 trigonal bipyramid,  a cornercorner with one N(4)CaHf4 trigonal bipyramid,  a cornercorner with one N(7)CaHf4 trigonal bipyramid,  a cornercorner with one O(2)CaHf4 trigonal bipyramid,  a cornercorner with one O(4)CaHf4 trigonal bipyramid, corners with two equivalent N(6)Hf4 trigonal pyramids,  an edgeedge with one N(3)CaHf4 trigonal bipyramid,  an edgeedge with one N(7)CaHf4 trigonal bipyramid,  an edgeedge with one O(4)CaHf4 trigonal bipyramid, edges with two equivalent N(4)CaHf4 trigonal bipyramids, and edges with two equivalent O(2)CaHf4 trigonal bipyramids. In the second N site, N(2) is bonded in a rectangular see-saw-like geometry to one Hf(1), one Hf(3), one Hf(6), and one Hf(7) atom. In the third N site, N(3) is bonded to one Ca(1), one Hf(2), one Hf(4), one Hf(5), and one Hf(8) atom to form distorted NCaHf4 trigonal bipyramids that share  a cornercorner with one N(1)CaHf4 trigonal bipyramid,  a cornercorner with one N(4)CaHf4 trigonal bipyramid,  a cornercorner with one N(7)CaHf4 trigonal bipyramid,  a cornercorner with one O(2)CaHf4 trigonal bipyramid,  a cornercorner with one O(4)CaHf4 trigonal bipyramid, corners with two equivalent O(3)Hf4 trigonal pyramids,  an edgeedge with one N(1)CaHf4 trigonal bipyramid,  an edgeedge with one N(4)CaHf4 trigonal bipyramid,  an edgeedge with one O(2)CaHf4 trigonal bipyramid, edges with two equivalent N(7)CaHf4 trigonal bipyramids, and edges with two equivalent O(4)CaHf4 trigonal bipyramids. In the fourth N site, N(4) is bonded to one Ca(1), one Hf(1), one Hf(4), one Hf(5), and one Hf(6) atom to form distorted NCaHf4 trigonal bipyramids that share  a cornercorner with one N(1)CaHf4 trigonal bipyramid,  a cornercorner with one N(3)CaHf4 trigonal bipyramid,  a cornercorner with one N(7)CaHf4 trigonal bipyramid,  a cornercorner with one O(2)CaHf4 trigonal bipyramid,  a cornercorner with one O(4)CaHf4 trigonal bipyramid, corners with two equivalent N(6)Hf4 trigonal pyramids,  an edgeedge with one N(3)CaHf4 trigonal bipyramid,  an edgeedge with one N(7)CaHf4 trigonal bipyramid,  an edgeedge with one O(4)CaHf4 trigonal bipyramid, edges with two equivalent N(1)CaHf4 trigonal bipyramids, and edges with two equivalent O(2)CaHf4 trigonal bipyramids. In the fifth N site, N(5) is bonded in a distorted see-saw-like geometry to one Hf(2), one Hf(3), one Hf(7), and one Hf(8) atom. In the sixth N site, N(6) is bonded to one Hf(1), one Hf(3), one Hf(6), and one Hf(7) atom to form distorted NHf4 trigonal pyramids that share corners with two equivalent N(1)CaHf4 trigonal bipyramids, corners with two equivalent N(4)CaHf4 trigonal bipyramids,  an edgeedge with one O(2)CaHf4 trigonal bipyramid, and  an edgeedge with one O(3)Hf4 trigonal pyramid. In the seventh N site, N(7) is bonded to one Ca(1), one Hf(2), one Hf(4), one Hf(5), and one Hf(8) atom to form distorted NCaHf4 trigonal bipyramids that share  a cornercorner with one N(1)CaHf4 trigonal bipyramid,  a cornercorner with one N(3)CaHf4 trigonal bipyramid,  a cornercorner with one N(4)CaHf4 trigonal bipyramid,  a cornercorner with one O(2)CaHf4 trigonal bipyramid,  a cornercorner with one O(4)CaHf4 trigonal bipyramid,  an edgeedge with one N(1)CaHf4 trigonal bipyramid,  an edgeedge with one N(4)CaHf4 trigonal bipyramid,  an edgeedge with one O(2)CaHf4 trigonal bipyramid, edges with two equivalent N(3)CaHf4 trigonal bipyramids, edges with two equivalent O(4)CaHf4 trigonal bipyramids, and  an edgeedge with one O(3)Hf4 trigonal pyramid. In the eighth N site, N(8) is bonded in a distorted rectangular see-saw-like geometry to one Hf(2), one Hf(3), one Hf(7), and one Hf(8) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Hf(1), one Hf(3), one Hf(6), and one Hf(7) atom. In the second O site, O(2) is bonded to one Ca(1), one Hf(1), one Hf(4), one Hf(5), and one Hf(6) atom to form distorted OCaHf4 trigonal bipyramids that share  a cornercorner with one N(1)CaHf4 trigonal bipyramid,  a cornercorner with one N(3)CaHf4 trigonal bipyramid,  a cornercorner with one N(4)CaHf4 trigonal bipyramid,  a cornercorner with one N(7)CaHf4 trigonal bipyramid,  a cornercorner with one O(4)CaHf4 trigonal bipyramid,  an edgeedge with one N(3)CaHf4 trigonal bipyramid,  an edgeedge with one N(7)CaHf4 trigonal bipyramid,  an edgeedge with one O(4)CaHf4 trigonal bipyramid, edges with two equivalent N(1)CaHf4 trigonal bipyramids, edges with two equivalent N(4)CaHf4 trigonal bipyramids, and  an edgeedge with one N(6)Hf4 trigonal pyramid. In the third O site, O(3) is bonded to one Hf(2), one Hf(3), one Hf(7), and one Hf(8) atom to form distorted OHf4 trigonal pyramids that share corners with two equivalent N(3)CaHf4 trigonal bipyramids, corners with two equivalent O(4)CaHf4 trigonal bipyramids,  an edgeedge with one N(7)CaHf4 trigonal bipyramid, and  an edgeedge with one N(6)Hf4 trigonal pyramid. In the fourth O site, O(4) is bonded to one Ca(1), one Hf(2), one Hf(4), one Hf(5), and one Hf(8) atom to form distorted OCaHf4 trigonal bipyramids that share  a cornercorner with one N(1)CaHf4 trigonal bipyramid,  a cornercorner with one N(3)CaHf4 trigonal bipyramid,  a cornercorner with one N(4)CaHf4 trigonal bipyramid,  a cornercorner with one N(7)CaHf4 trigonal bipyramid,  a cornercorner with one O(2)CaHf4 trigonal bipyramid, corners with two equivalent O(3)Hf4 trigonal pyramids,  an edgeedge with one N(1)CaHf4 trigonal bipyramid,  an edgeedge with one N(4)CaHf4 trigonal bipyramid,  an edgeedge with one O(2)CaHf4 trigonal bipyramid, edges with two equivalent N(3)CaHf4 trigonal bipyramids, and edges with two equivalent N(7)CaHf4 trigonal bipyramids.
CaHf8(N2O)4 crystallizes in the triclinic P1 space group. Ca(1) is bonded to one N(1), one N(3), one N(4), one N(7), one O(2), and one O(4) atom to form CaN4O2 octahedra that share corners with three equivalent Hf(2)N4O2 octahedra, corners with three equivalent Hf(6)N4O2 octahedra,  a faceface with one Hf(1)N4O2 octahedra, and  a faceface with one Hf(8)N4O2 octahedra. The corner-sharing octahedral tilt angles range from 38-49°. The Ca(1)-N(1) bond length is 2.34 Å. The Ca(1)-N(3) bond length is 2.34 Å. The Ca(1)-N(4) bond length is 2.34 Å. The Ca(1)-N(7) bond length is 2.35 Å. The Ca(1)-O(2) bond length is 2.29 Å. The Ca(1)-O(4) bond length is 2.27 Å. There are eight inequivalent Hf sites. In the first Hf site, Hf(1) is bonded to one N(1), one N(2), one N(4), one N(6), one O(1), and one O(2) atom to form distorted HfN4O2 octahedra that share edges with three equivalent Hf(6)N4O2 octahedra and  a faceface with one Ca(1)N4O2 octahedra. The Hf(1)-N(1) bond length is 2.40 Å. The Hf(1)-N(2) bond length is 2.15 Å. The Hf(1)-N(4) bond length is 2.37 Å. The Hf(1)-N(6) bond length is 2.08 Å. The Hf(1)-O(1) bond length is 2.07 Å. The Hf(1)-O(2) bond length is 2.35 Å. In the second Hf site, Hf(2) is bonded to one N(3), one N(5), one N(7), one N(8), one O(3), and one O(4) atom to form distorted HfN4O2 octahedra that share corners with three equivalent Ca(1)N4O2 octahedra and edges with three equivalent Hf(8)N4O2 octahedra. The corner-sharing octahedral tilt angles range from 38-49°. The Hf(2)-N(3) bond length is 2.13 Å. The Hf(2)-N(5) bond length is 2.19 Å. The Hf(2)-N(7) bond length is 2.23 Å. The Hf(2)-N(8) bond length is 2.07 Å. The Hf(2)-O(3) bond length is 2.24 Å. The Hf(2)-O(4) bond length is 2.58 Å. In the third Hf site, Hf(3) is bonded in a 6-coordinate geometry to one N(2), one N(5), one N(6), one N(8), one O(1), and one O(3) atom. The Hf(3)-N(2) bond length is 2.26 Å. The Hf(3)-N(5) bond length is 2.03 Å. The Hf(3)-N(6) bond length is 2.30 Å. The Hf(3)-N(8) bond length is 2.14 Å. The Hf(3)-O(1) bond length is 2.70 Å. The Hf(3)-O(3) bond length is 2.16 Å. In the fourth Hf site, Hf(4) is bonded in a 6-coordinate geometry to one N(1), one N(3), one N(4), one N(7), one O(2), and one O(4) atom. The Hf(4)-N(1) bond length is 2.44 Å. The Hf(4)-N(3) bond length is 2.05 Å. The Hf(4)-N(4) bond length is 2.25 Å. The Hf(4)-N(7) bond length is 2.13 Å. The Hf(4)-O(2) bond length is 2.53 Å. The Hf(4)-O(4) bond length is 2.18 Å. In the fifth Hf site, Hf(5) is bonded in a 6-coordinate geometry to one N(1), one N(3), one N(4), one N(7), one O(2), and one O(4) atom. The Hf(5)-N(1) bond length is 2.08 Å. The Hf(5)-N(3) bond length is 2.51 Å. The Hf(5)-N(4) bond length is 2.14 Å. The Hf(5)-N(7) bond length is 2.34 Å. The Hf(5)-O(2) bond length is 2.11 Å. The Hf(5)-O(4) bond length is 2.34 Å. In the sixth Hf site, Hf(6) is bonded to one N(1), one N(2), one N(4), one N(6), one O(1), and one O(2) atom to form HfN4O2 octahedra that share corners with three equivalent Ca(1)N4O2 octahedra and edges with three equivalent Hf(1)N4O2 octahedra. The corner-sharing octahedral tilt angles range from 39-48°. The Hf(6)-N(1) bond length is 2.15 Å. The Hf(6)-N(2) bond length is 2.09 Å. The Hf(6)-N(4) bond length is 2.28 Å. The Hf(6)-N(6) bond length is 2.18 Å. The Hf(6)-O(1) bond length is 2.21 Å. The Hf(6)-O(2) bond length is 2.40 Å. In the seventh Hf site, Hf(7) is bonded in a 6-coordinate geometry to one N(2), one N(5), one N(6), one N(8), one O(1), and one O(3) atom. The Hf(7)-N(2) bond length is 2.14 Å. The Hf(7)-N(5) bond length is 2.30 Å. The Hf(7)-N(6) bond length is 2.10 Å. The Hf(7)-N(8) bond length is 2.45 Å. The Hf(7)-O(1) bond length is 2.06 Å. The Hf(7)-O(3) bond length is 2.36 Å. In the eighth Hf site, Hf(8) is bonded to one N(3), one N(5), one N(7), one N(8), one O(3), and one O(4) atom to form distorted HfN4O2 octahedra that share edges with three equivalent Hf(2)N4O2 octahedra and  a faceface with one Ca(1)N4O2 octahedra. The Hf(8)-N(3) bond length is 2.44 Å. The Hf(8)-N(5) bond length is 2.07 Å. The Hf(8)-N(7) bond length is 2.31 Å. The Hf(8)-N(8) bond length is 2.11 Å. The Hf(8)-O(3) bond length is 2.11 Å. The Hf(8)-O(4) bond length is 2.33 Å. There are eight inequivalent N sites. In the first N site, N(1) is bonded to one Ca(1), one Hf(1), one Hf(4), one Hf(5), and one Hf(6) atom to form distorted NCaHf4 trigonal bipyramids that share  a cornercorner with one N(3)CaHf4 trigonal bipyramid,  a cornercorner with one N(4)CaHf4 trigonal bipyramid,  a cornercorner with one N(7)CaHf4 trigonal bipyramid,  a cornercorner with one O(2)CaHf4 trigonal bipyramid,  a cornercorner with one O(4)CaHf4 trigonal bipyramid, corners with two equivalent N(6)Hf4 trigonal pyramids,  an edgeedge with one N(3)CaHf4 trigonal bipyramid,  an edgeedge with one N(7)CaHf4 trigonal bipyramid,  an edgeedge with one O(4)CaHf4 trigonal bipyramid, edges with two equivalent N(4)CaHf4 trigonal bipyramids, and edges with two equivalent O(2)CaHf4 trigonal bipyramids. In the second N site, N(2) is bonded in a rectangular see-saw-like geometry to one Hf(1), one Hf(3), one Hf(6), and one Hf(7) atom. In the third N site, N(3) is bonded to one Ca(1), one Hf(2), one Hf(4), one Hf(5), and one Hf(8) atom to form distorted NCaHf4 trigonal bipyramids that share  a cornercorner with one N(1)CaHf4 trigonal bipyramid,  a cornercorner with one N(4)CaHf4 trigonal bipyramid,  a cornercorner with one N(7)CaHf4 trigonal bipyramid,  a cornercorner with one O(2)CaHf4 trigonal bipyramid,  a cornercorner with one O(4)CaHf4 trigonal bipyramid, corners with two equivalent O(3)Hf4 trigonal pyramids,  an edgeedge with one N(1)CaHf4 trigonal bipyramid,  an edgeedge with one N(4)CaHf4 trigonal bipyramid,  an edgeedge with one O(2)CaHf4 trigonal bipyramid, edges with two equivalent N(7)CaHf4 trigonal bipyramids, and edges with two equivalent O(4)CaHf4 trigonal bipyramids. In the fourth N site, N(4) is bonded to one Ca(1), one Hf(1), one Hf(4), one Hf(5), and one Hf(6) atom to form distorted NCaHf4 trigonal bipyramids that share  a cornercorner with one N(1)CaHf4 trigonal bipyramid,  a cornercorner with one N(3)CaHf4 trigonal bipyramid,  a cornercorner with one N(7)CaHf4 trigonal bipyramid,  a cornercorner with one O(2)CaHf4 trigonal bipyramid,  a cornercorner with one O(4)CaHf4 trigonal bipyramid, corners with two equivalent N(6)Hf4 trigonal pyramids,  an edgeedge with one N(3)CaHf4 trigonal bipyramid,  an edgeedge with one N(7)CaHf4 trigonal bipyramid,  an edgeedge with one O(4)CaHf4 trigonal bipyramid, edges with two equivalent N(1)CaHf4 trigonal bipyramids, and edges with two equivalent O(2)CaHf4 trigonal bipyramids. In the fifth N site, N(5) is bonded in a distorted see-saw-like geometry to one Hf(2), one Hf(3), one Hf(7), and one Hf(8) atom. In the sixth N site, N(6) is bonded to one Hf(1), one Hf(3), one Hf(6), and one Hf(7) atom to form distorted NHf4 trigonal pyramids that share corners with two equivalent N(1)CaHf4 trigonal bipyramids, corners with two equivalent N(4)CaHf4 trigonal bipyramids,  an edgeedge with one O(2)CaHf4 trigonal bipyramid, and  an edgeedge with one O(3)Hf4 trigonal pyramid. In the seventh N site, N(7) is bonded to one Ca(1), one Hf(2), one Hf(4), one Hf(5), and one Hf(8) atom to form distorted NCaHf4 trigonal bipyramids that share  a cornercorner with one N(1)CaHf4 trigonal bipyramid,  a cornercorner with one N(3)CaHf4 trigonal bipyramid,  a cornercorner with one N(4)CaHf4 trigonal bipyramid,  a cornercorner with one O(2)CaHf4 trigonal bipyramid,  a cornercorner with one O(4)CaHf4 trigonal bipyramid,  an edgeedge with one N(1)CaHf4 trigonal bipyramid,  an edgeedge with one N(4)CaHf4 trigonal bipyramid,  an edgeedge with one O(2)CaHf4 trigonal bipyramid, edges with two equivalent N(3)CaHf4 trigonal bipyramids, edges with two equivalent O(4)CaHf4 trigonal bipyramids, and  an edgeedge with one O(3)Hf4 trigonal pyramid. In the eighth N site, N(8) is bonded in a distorted rectangular see-saw-like geometry to one Hf(2), one Hf(3), one Hf(7), and one Hf(8) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Hf(1), one Hf(3), one Hf(6), and one Hf(7) atom. In the second O site, O(2) is bonded to one Ca(1), one Hf(1), one Hf(4), one Hf(5), and one Hf(6) atom to form distorted OCaHf4 trigonal bipyramids that share  a cornercorner with one N(1)CaHf4 trigonal bipyramid,  a cornercorner with one N(3)CaHf4 trigonal bipyramid,  a cornercorner with one N(4)CaHf4 trigonal bipyramid,  a cornercorner with one N(7)CaHf4 trigonal bipyramid,  a cornercorner with one O(4)CaHf4 trigonal bipyramid,  an edgeedge with one N(3)CaHf4 trigonal bipyramid,  an edgeedge with one N(7)CaHf4 trigonal bipyramid,  an edgeedge with one O(4)CaHf4 trigonal bipyramid, edges with two equivalent N(1)CaHf4 trigonal bipyramids, edges with two equivalent N(4)CaHf4 trigonal bipyramids, and  an edgeedge with one N(6)Hf4 trigonal pyramid. In the third O site, O(3) is bonded to one Hf(2), one Hf(3), one Hf(7), and one Hf(8) atom to form distorted OHf4 trigonal pyramids that share corners with two equivalent N(3)CaHf4 trigonal bipyramids, corners with two equivalent O(4)CaHf4 trigonal bipyramids,  an edgeedge with one N(7)CaHf4 trigonal bipyramid, and  an edgeedge with one N(6)Hf4 trigonal pyramid. In the fourth O site, O(4) is bonded to one Ca(1), one Hf(2), one Hf(4), one Hf(5), and one Hf(8) atom to form distorted OCaHf4 trigonal bipyramids that share  a cornercorner with one N(1)CaHf4 trigonal bipyramid,  a cornercorner with one N(3)CaHf4 trigonal bipyramid,  a cornercorner with one N(4)CaHf4 trigonal bipyramid,  a cornercorner with one N(7)CaHf4 trigonal bipyramid,  a cornercorner with one O(2)CaHf4 trigonal bipyramid, corners with two equivalent O(3)Hf4 trigonal pyramids,  an edgeedge with one N(1)CaHf4 trigonal bipyramid,  an edgeedge with one N(4)CaHf4 trigonal bipyramid,  an edgeedge with one O(2)CaHf4 trigonal bipyramid, edges with two equivalent N(3)CaHf4 trigonal bipyramids, and edges with two equivalent N(7)CaHf4 trigonal bipyramids.