CrO2 crystallizes in the triclinic P1 space group. There are twelve inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(2), one O(3), one O(4), one O(6), one O(7), and one O(8) atom to form distorted CrO6 octahedra that share  a cornercorner with one Cr(12)O4 tetrahedra,  an edgeedge with one Cr(3)O6 octahedra, edges with two equivalent Cr(4)O6 octahedra, and edges with two equivalent Cr(6)O6 octahedra. In the second Cr site, Cr(2) is bonded to one O(10), one O(15), one O(16), one O(20), one O(5), and one O(9) atom to form edge-sharing CrO6 octahedra. In the third Cr site, Cr(3) is bonded to one O(11), one O(12), one O(5), one O(6), one O(8), and one O(9) atom to form edge-sharing CrO6 octahedra. In the fourth Cr site, Cr(4) is bonded to one O(1), one O(12), one O(3), one O(4), one O(6), and one O(7) atom to form distorted CrO6 octahedra that share  a cornercorner with one Cr(12)O4 tetrahedra,  an edgeedge with one Cr(3)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, and edges with two equivalent Cr(6)O6 octahedra. In the fifth Cr site, Cr(5) is bonded to one O(10), one O(11), one O(14), one O(15), one O(16), and one O(9) atom to form edge-sharing CrO6 octahedra. In the sixth Cr site, Cr(6) is bonded to one O(1), one O(12), one O(2), one O(3), one O(7), and one O(8) atom to form CrO6 octahedra that share  a cornercorner with one Cr(12)O4 tetrahedra,  an edgeedge with one Cr(3)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, and edges with two equivalent Cr(4)O6 octahedra. In the seventh Cr site, Cr(7) is bonded to one O(13), one O(14), one O(16), one O(18), one O(19), and one O(20) atom to form edge-sharing CrO6 octahedra. In the eighth Cr site, Cr(8) is bonded to one O(10), one O(11), one O(14), one O(15), one O(20), and one O(5) atom to form edge-sharing CrO6 octahedra. In the ninth Cr site, Cr(9) is bonded to one O(17), one O(18), one O(19), one O(21), one O(22), and one O(23) atom to form CrO6 octahedra that share corners with two equivalent Cr(12)O4 tetrahedra,  an edgeedge with one Cr(7)O6 octahedra, edges with two equivalent Cr(10)O6 octahedra, and edges with two equivalent Cr(11)O6 octahedra. In the tenth Cr site, Cr(10) is bonded to one O(13), one O(17), one O(19), one O(21), one O(23), and one O(24) atom to form CrO6 octahedra that share corners with two equivalent Cr(12)O4 tetrahedra,  an edgeedge with one Cr(7)O6 octahedra, edges with two equivalent Cr(11)O6 octahedra, and edges with two equivalent Cr(9)O6 octahedra. In the eleventh Cr site, Cr(11) is bonded to one O(13), one O(17), one O(18), one O(22), one O(23), and one O(24) atom to form CrO6 octahedra that share corners with two equivalent Cr(12)O4 tetrahedra,  an edgeedge with one Cr(7)O6 octahedra, edges with two equivalent Cr(10)O6 octahedra, and edges with two equivalent Cr(9)O6 octahedra. In the twelfth Cr site, Cr(12) is bonded to one O(21), one O(22), one O(24), and one O(7) atom to form corner-sharing CrO4 tetrahedra. The corner-sharing octahedral tilt angles range from 53-57°. There are twenty-four inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to one Cr(4) and one Cr(6) atom. In the second O site, O(2) is bonded in a water-like geometry to one Cr(1) and one Cr(6) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Cr(1), one Cr(4), and one Cr(6) atom. In the fourth O site, O(4) is bonded in a water-like geometry to one Cr(1) and one Cr(4) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Cr(2), one Cr(3), and one Cr(8) atom. In the sixth O site, O(6) is bonded in a trigonal non-coplanar geometry to one Cr(1), one Cr(3), and one Cr(4) atom. In the seventh O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to one Cr(1), one Cr(12), one Cr(4), and one Cr(6) atom. In the eighth O site, O(8) is bonded in a trigonal non-coplanar geometry to one Cr(1), one Cr(3), and one Cr(6) atom. In the ninth O site, O(9) is bonded in a distorted trigonal non-coplanar geometry to one Cr(2), one Cr(3), and one Cr(5) atom. In the tenth O site, O(10) is bonded in a distorted trigonal non-coplanar geometry to one Cr(2), one Cr(5), and one Cr(8) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal non-coplanar geometry to one Cr(3), one Cr(5), and one Cr(8) atom. In the twelfth O site, O(12) is bonded in a trigonal non-coplanar geometry to one Cr(3), one Cr(4), and one Cr(6) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal non-coplanar geometry to one Cr(10), one Cr(11), and one Cr(7) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal non-coplanar geometry to one Cr(5), one Cr(7), and one Cr(8) atom. In the fifteenth O site, O(15) is bonded in a distorted trigonal non-coplanar geometry to one Cr(2), one Cr(5), and one Cr(8) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal non-coplanar geometry to one Cr(2), one Cr(5), and one Cr(7) atom. In the seventeenth O site, O(17) is bonded in a distorted T-shaped geometry to one Cr(10), one Cr(11), and one Cr(9) atom. In the eighteenth O site, O(18) is bonded in a distorted trigonal non-coplanar geometry to one Cr(11), one Cr(7), and one Cr(9) atom. In the nineteenth O site, O(19) is bonded in a distorted T-shaped geometry to one Cr(10), one Cr(7), and one Cr(9) atom. In the twentieth O site, O(20) is bonded in a distorted trigonal non-coplanar geometry to one Cr(2), one Cr(7), and one Cr(8) atom. In the twenty-first O site, O(21) is bonded in a distorted trigonal planar geometry to one Cr(10), one Cr(12), and one Cr(9) atom. In the twenty-second O site, O(22) is bonded in a distorted trigonal planar geometry to one Cr(11), one Cr(12), and one Cr(9) atom. In the twenty-third O site, O(23) is bonded in a trigonal non-coplanar geometry to one Cr(10), one Cr(11), and one Cr(9) atom. In the twenty-fourth O site, O(24) is bonded in a distorted trigonal planar geometry to one Cr(10), one Cr(11), and one Cr(12) atom.
CrO2 crystallizes in the triclinic P1 space group. There are twelve inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(2), one O(3), one O(4), one O(6), one O(7), and one O(8) atom to form distorted CrO6 octahedra that share  a cornercorner with one Cr(12)O4 tetrahedra,  an edgeedge with one Cr(3)O6 octahedra, edges with two equivalent Cr(4)O6 octahedra, and edges with two equivalent Cr(6)O6 octahedra. The Cr(1)-O(2) bond length is 1.84 Å. The Cr(1)-O(3) bond length is 1.94 Å. The Cr(1)-O(4) bond length is 1.84 Å. The Cr(1)-O(6) bond length is 1.98 Å. The Cr(1)-O(7) bond length is 2.16 Å. The Cr(1)-O(8) bond length is 1.98 Å. In the second Cr site, Cr(2) is bonded to one O(10), one O(15), one O(16), one O(20), one O(5), and one O(9) atom to form edge-sharing CrO6 octahedra. The Cr(2)-O(10) bond length is 1.96 Å. The Cr(2)-O(15) bond length is 1.96 Å. The Cr(2)-O(16) bond length is 1.96 Å. The Cr(2)-O(20) bond length is 1.96 Å. The Cr(2)-O(5) bond length is 1.95 Å. The Cr(2)-O(9) bond length is 1.95 Å. In the third Cr site, Cr(3) is bonded to one O(11), one O(12), one O(5), one O(6), one O(8), and one O(9) atom to form edge-sharing CrO6 octahedra. The Cr(3)-O(11) bond length is 1.97 Å. The Cr(3)-O(12) bond length is 1.91 Å. The Cr(3)-O(5) bond length is 1.97 Å. The Cr(3)-O(6) bond length is 1.91 Å. The Cr(3)-O(8) bond length is 1.91 Å. The Cr(3)-O(9) bond length is 1.96 Å. In the fourth Cr site, Cr(4) is bonded to one O(1), one O(12), one O(3), one O(4), one O(6), and one O(7) atom to form distorted CrO6 octahedra that share  a cornercorner with one Cr(12)O4 tetrahedra,  an edgeedge with one Cr(3)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, and edges with two equivalent Cr(6)O6 octahedra. The Cr(4)-O(1) bond length is 1.84 Å. The Cr(4)-O(12) bond length is 1.98 Å. The Cr(4)-O(3) bond length is 1.94 Å. The Cr(4)-O(4) bond length is 1.84 Å. The Cr(4)-O(6) bond length is 1.98 Å. The Cr(4)-O(7) bond length is 2.17 Å. In the fifth Cr site, Cr(5) is bonded to one O(10), one O(11), one O(14), one O(15), one O(16), and one O(9) atom to form edge-sharing CrO6 octahedra. The Cr(5)-O(10) bond length is 1.96 Å. The Cr(5)-O(11) bond length is 1.95 Å. The Cr(5)-O(14) bond length is 1.96 Å. The Cr(5)-O(15) bond length is 1.96 Å. The Cr(5)-O(16) bond length is 1.95 Å. The Cr(5)-O(9) bond length is 1.94 Å. In the sixth Cr site, Cr(6) is bonded to one O(1), one O(12), one O(2), one O(3), one O(7), and one O(8) atom to form CrO6 octahedra that share  a cornercorner with one Cr(12)O4 tetrahedra,  an edgeedge with one Cr(3)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, and edges with two equivalent Cr(4)O6 octahedra. The Cr(6)-O(1) bond length is 1.84 Å. The Cr(6)-O(12) bond length is 1.98 Å. The Cr(6)-O(2) bond length is 1.84 Å. The Cr(6)-O(3) bond length is 1.94 Å. The Cr(6)-O(7) bond length is 2.16 Å. The Cr(6)-O(8) bond length is 1.98 Å. In the seventh Cr site, Cr(7) is bonded to one O(13), one O(14), one O(16), one O(18), one O(19), and one O(20) atom to form edge-sharing CrO6 octahedra. The Cr(7)-O(13) bond length is 1.94 Å. The Cr(7)-O(14) bond length is 1.94 Å. The Cr(7)-O(16) bond length is 1.94 Å. The Cr(7)-O(18) bond length is 1.94 Å. The Cr(7)-O(19) bond length is 1.94 Å. The Cr(7)-O(20) bond length is 1.94 Å. In the eighth Cr site, Cr(8) is bonded to one O(10), one O(11), one O(14), one O(15), one O(20), and one O(5) atom to form edge-sharing CrO6 octahedra. The Cr(8)-O(10) bond length is 1.97 Å. The Cr(8)-O(11) bond length is 1.94 Å. The Cr(8)-O(14) bond length is 1.95 Å. The Cr(8)-O(15) bond length is 1.97 Å. The Cr(8)-O(20) bond length is 1.95 Å. The Cr(8)-O(5) bond length is 1.94 Å. In the ninth Cr site, Cr(9) is bonded to one O(17), one O(18), one O(19), one O(21), one O(22), and one O(23) atom to form CrO6 octahedra that share corners with two equivalent Cr(12)O4 tetrahedra,  an edgeedge with one Cr(7)O6 octahedra, edges with two equivalent Cr(10)O6 octahedra, and edges with two equivalent Cr(11)O6 octahedra. The Cr(9)-O(17) bond length is 1.95 Å. The Cr(9)-O(18) bond length is 1.95 Å. The Cr(9)-O(19) bond length is 1.95 Å. The Cr(9)-O(21) bond length is 2.07 Å. The Cr(9)-O(22) bond length is 2.06 Å. The Cr(9)-O(23) bond length is 1.91 Å. In the tenth Cr site, Cr(10) is bonded to one O(13), one O(17), one O(19), one O(21), one O(23), and one O(24) atom to form CrO6 octahedra that share corners with two equivalent Cr(12)O4 tetrahedra,  an edgeedge with one Cr(7)O6 octahedra, edges with two equivalent Cr(11)O6 octahedra, and edges with two equivalent Cr(9)O6 octahedra. The Cr(10)-O(13) bond length is 1.94 Å. The Cr(10)-O(17) bond length is 1.96 Å. The Cr(10)-O(19) bond length is 1.94 Å. The Cr(10)-O(21) bond length is 2.08 Å. The Cr(10)-O(23) bond length is 1.90 Å. The Cr(10)-O(24) bond length is 2.07 Å. In the eleventh Cr site, Cr(11) is bonded to one O(13), one O(17), one O(18), one O(22), one O(23), and one O(24) atom to form CrO6 octahedra that share corners with two equivalent Cr(12)O4 tetrahedra,  an edgeedge with one Cr(7)O6 octahedra, edges with two equivalent Cr(10)O6 octahedra, and edges with two equivalent Cr(9)O6 octahedra. The Cr(11)-O(13) bond length is 1.96 Å. The Cr(11)-O(17) bond length is 1.95 Å. The Cr(11)-O(18) bond length is 1.96 Å. The Cr(11)-O(22) bond length is 2.04 Å. The Cr(11)-O(23) bond length is 1.93 Å. The Cr(11)-O(24) bond length is 2.05 Å. In the twelfth Cr site, Cr(12) is bonded to one O(21), one O(22), one O(24), and one O(7) atom to form corner-sharing CrO4 tetrahedra. The corner-sharing octahedral tilt angles range from 53-57°. The Cr(12)-O(21) bond length is 1.77 Å. The Cr(12)-O(22) bond length is 1.79 Å. The Cr(12)-O(24) bond length is 1.78 Å. The Cr(12)-O(7) bond length is 1.85 Å. There are twenty-four inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to one Cr(4) and one Cr(6) atom. In the second O site, O(2) is bonded in a water-like geometry to one Cr(1) and one Cr(6) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Cr(1), one Cr(4), and one Cr(6) atom. In the fourth O site, O(4) is bonded in a water-like geometry to one Cr(1) and one Cr(4) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Cr(2), one Cr(3), and one Cr(8) atom. In the sixth O site, O(6) is bonded in a trigonal non-coplanar geometry to one Cr(1), one Cr(3), and one Cr(4) atom. In the seventh O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to one Cr(1), one Cr(12), one Cr(4), and one Cr(6) atom. In the eighth O site, O(8) is bonded in a trigonal non-coplanar geometry to one Cr(1), one Cr(3), and one Cr(6) atom. In the ninth O site, O(9) is bonded in a distorted trigonal non-coplanar geometry to one Cr(2), one Cr(3), and one Cr(5) atom. In the tenth O site, O(10) is bonded in a distorted trigonal non-coplanar geometry to one Cr(2), one Cr(5), and one Cr(8) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal non-coplanar geometry to one Cr(3), one Cr(5), and one Cr(8) atom. In the twelfth O site, O(12) is bonded in a trigonal non-coplanar geometry to one Cr(3), one Cr(4), and one Cr(6) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal non-coplanar geometry to one Cr(10), one Cr(11), and one Cr(7) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal non-coplanar geometry to one Cr(5), one Cr(7), and one Cr(8) atom. In the fifteenth O site, O(15) is bonded in a distorted trigonal non-coplanar geometry to one Cr(2), one Cr(5), and one Cr(8) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal non-coplanar geometry to one Cr(2), one Cr(5), and one Cr(7) atom. In the seventeenth O site, O(17) is bonded in a distorted T-shaped geometry to one Cr(10), one Cr(11), and one Cr(9) atom. In the eighteenth O site, O(18) is bonded in a distorted trigonal non-coplanar geometry to one Cr(11), one Cr(7), and one Cr(9) atom. In the nineteenth O site, O(19) is bonded in a distorted T-shaped geometry to one Cr(10), one Cr(7), and one Cr(9) atom. In the twentieth O site, O(20) is bonded in a distorted trigonal non-coplanar geometry to one Cr(2), one Cr(7), and one Cr(8) atom. In the twenty-first O site, O(21) is bonded in a distorted trigonal planar geometry to one Cr(10), one Cr(12), and one Cr(9) atom. In the twenty-second O site, O(22) is bonded in a distorted trigonal planar geometry to one Cr(11), one Cr(12), and one Cr(9) atom. In the twenty-third O site, O(23) is bonded in a trigonal non-coplanar geometry to one Cr(10), one Cr(11), and one Cr(9) atom. In the twenty-fourth O site, O(24) is bonded in a distorted trigonal planar geometry to one Cr(10), one Cr(11), and one Cr(12) atom.