BiO2 crystallizes in the triclinic P1 space group. There are twelve inequivalent Bi sites. In the first Bi site, Bi(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 BiO6 octahedra that share  a cornercorner with one Bi(12)O4 tetrahedra,  an edgeedge with one Bi(3)O6 octahedra, and edges with two equivalent Bi(6)O6 octahedra. In the second Bi site, Bi(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 distorted edge-sharing BiO6 octahedra. In the third Bi site, Bi(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 BiO6 octahedra. In the fourth Bi site, Bi(4) is bonded in a 6-coordinate geometry to one O(1), one O(12), one O(3), one O(4), one O(6), and one O(7) atom. In the fifth Bi site, Bi(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 distorted edge-sharing BiO6 octahedra. In the sixth Bi site, Bi(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 BiO6 octahedra that share  a cornercorner with one Bi(12)O4 tetrahedra,  an edgeedge with one Bi(3)O6 octahedra, and edges with two equivalent Bi(1)O6 octahedra. In the seventh Bi site, Bi(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 BiO6 octahedra. In the eighth Bi site, Bi(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 BiO6 octahedra. In the ninth Bi site, Bi(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 BiO6 octahedra that share corners with two equivalent Bi(12)O4 tetrahedra,  an edgeedge with one Bi(7)O6 octahedra, edges with two equivalent Bi(10)O6 octahedra, and edges with two equivalent Bi(11)O6 octahedra. In the tenth Bi site, Bi(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 distorted BiO6 octahedra that share corners with two equivalent Bi(12)O4 tetrahedra,  an edgeedge with one Bi(7)O6 octahedra, edges with two equivalent Bi(11)O6 octahedra, and edges with two equivalent Bi(9)O6 octahedra. In the eleventh Bi site, Bi(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 distorted BiO6 octahedra that share corners with two equivalent Bi(12)O4 tetrahedra,  an edgeedge with one Bi(7)O6 octahedra, edges with two equivalent Bi(10)O6 octahedra, and edges with two equivalent Bi(9)O6 octahedra. In the twelfth Bi site, Bi(12) is bonded to one O(21), one O(22), one O(24), and one O(7) atom to form corner-sharing BiO4 tetrahedra. The corner-sharing octahedral tilt angles range from 45-62°. There are twenty-four inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to one Bi(4) and one Bi(6) atom. In the second O site, O(2) is bonded in a water-like geometry to one Bi(1) and one Bi(6) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Bi(1), one Bi(4), and one Bi(6) atom. In the fourth O site, O(4) is bonded in a water-like geometry to one Bi(1) and one Bi(4) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Bi(2), one Bi(3), and one Bi(8) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Bi(1), one Bi(3), and one Bi(4) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Bi(1), one Bi(12), one Bi(4), and one Bi(6) atom. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Bi(1), one Bi(3), and one Bi(6) atom. In the ninth O site, O(9) is bonded in a distorted trigonal non-coplanar geometry to one Bi(2), one Bi(3), and one Bi(5) atom. In the tenth O site, O(10) is bonded in a trigonal non-coplanar geometry to one Bi(2), one Bi(5), and one Bi(8) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal non-coplanar geometry to one Bi(3), one Bi(5), and one Bi(8) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal non-coplanar geometry to one Bi(3), one Bi(4), and one Bi(6) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal non-coplanar geometry to one Bi(10), one Bi(11), and one Bi(7) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal non-coplanar geometry to one Bi(5), one Bi(7), and one Bi(8) atom. In the fifteenth O site, O(15) is bonded in a trigonal non-coplanar geometry to one Bi(2), one Bi(5), and one Bi(8) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal non-coplanar geometry to one Bi(2), one Bi(5), and one Bi(7) atom. In the seventeenth O site, O(17) is bonded in a distorted trigonal non-coplanar geometry to one Bi(10), one Bi(11), and one Bi(9) atom. In the eighteenth O site, O(18) is bonded in a distorted trigonal non-coplanar geometry to one Bi(11), one Bi(7), and one Bi(9) atom. In the nineteenth O site, O(19) is bonded in a distorted trigonal non-coplanar geometry to one Bi(10), one Bi(7), and one Bi(9) atom. In the twentieth O site, O(20) is bonded in a distorted trigonal non-coplanar geometry to one Bi(2), one Bi(7), and one Bi(8) atom. In the twenty-first O site, O(21) is bonded in a distorted trigonal planar geometry to one Bi(10), one Bi(12), and one Bi(9) atom. In the twenty-second O site, O(22) is bonded in a distorted trigonal planar geometry to one Bi(11), one Bi(12), and one Bi(9) atom. In the twenty-third O site, O(23) is bonded in a trigonal non-coplanar geometry to one Bi(10), one Bi(11), and one Bi(9) atom. In the twenty-fourth O site, O(24) is bonded in a distorted trigonal planar geometry to one Bi(10), one Bi(11), and one Bi(12) atom.
BiO2 crystallizes in the triclinic P1 space group. There are twelve inequivalent Bi sites. In the first Bi site, Bi(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 BiO6 octahedra that share  a cornercorner with one Bi(12)O4 tetrahedra,  an edgeedge with one Bi(3)O6 octahedra, and edges with two equivalent Bi(6)O6 octahedra. The Bi(1)-O(2) bond length is 2.15 Å. The Bi(1)-O(3) bond length is 2.27 Å. The Bi(1)-O(4) bond length is 2.07 Å. The Bi(1)-O(6) bond length is 2.15 Å. The Bi(1)-O(7) bond length is 2.24 Å. The Bi(1)-O(8) bond length is 2.33 Å. In the second Bi site, Bi(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 distorted edge-sharing BiO6 octahedra. The Bi(2)-O(10) bond length is 2.40 Å. The Bi(2)-O(15) bond length is 2.38 Å. The Bi(2)-O(16) bond length is 2.31 Å. The Bi(2)-O(20) bond length is 2.43 Å. The Bi(2)-O(5) bond length is 2.50 Å. The Bi(2)-O(9) bond length is 2.46 Å. In the third Bi site, Bi(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 BiO6 octahedra. The Bi(3)-O(11) bond length is 2.20 Å. The Bi(3)-O(12) bond length is 2.17 Å. The Bi(3)-O(5) bond length is 2.20 Å. The Bi(3)-O(6) bond length is 2.16 Å. The Bi(3)-O(8) bond length is 2.18 Å. The Bi(3)-O(9) bond length is 2.12 Å. In the fourth Bi site, Bi(4) is bonded in a 6-coordinate geometry to one O(1), one O(12), one O(3), one O(4), one O(6), and one O(7) atom. The Bi(4)-O(1) bond length is 2.18 Å. The Bi(4)-O(12) bond length is 2.74 Å. The Bi(4)-O(3) bond length is 2.23 Å. The Bi(4)-O(4) bond length is 2.18 Å. The Bi(4)-O(6) bond length is 2.73 Å. The Bi(4)-O(7) bond length is 2.81 Å. In the fifth Bi site, Bi(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 distorted edge-sharing BiO6 octahedra. The Bi(5)-O(10) bond length is 2.40 Å. The Bi(5)-O(11) bond length is 2.45 Å. The Bi(5)-O(14) bond length is 2.46 Å. The Bi(5)-O(15) bond length is 2.38 Å. The Bi(5)-O(16) bond length is 2.38 Å. The Bi(5)-O(9) bond length is 2.36 Å. In the sixth Bi site, Bi(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 BiO6 octahedra that share  a cornercorner with one Bi(12)O4 tetrahedra,  an edgeedge with one Bi(3)O6 octahedra, and edges with two equivalent Bi(1)O6 octahedra. The Bi(6)-O(1) bond length is 2.06 Å. The Bi(6)-O(12) bond length is 2.14 Å. The Bi(6)-O(2) bond length is 2.15 Å. The Bi(6)-O(3) bond length is 2.27 Å. The Bi(6)-O(7) bond length is 2.30 Å. The Bi(6)-O(8) bond length is 2.31 Å. In the seventh Bi site, Bi(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 BiO6 octahedra. The Bi(7)-O(13) bond length is 2.13 Å. The Bi(7)-O(14) bond length is 2.20 Å. The Bi(7)-O(16) bond length is 2.16 Å. The Bi(7)-O(18) bond length is 2.16 Å. The Bi(7)-O(19) bond length is 2.17 Å. The Bi(7)-O(20) bond length is 2.21 Å. In the eighth Bi site, Bi(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 BiO6 octahedra. The Bi(8)-O(10) bond length is 2.13 Å. The Bi(8)-O(11) bond length is 2.22 Å. The Bi(8)-O(14) bond length is 2.21 Å. The Bi(8)-O(15) bond length is 2.14 Å. The Bi(8)-O(20) bond length is 2.22 Å. The Bi(8)-O(5) bond length is 2.20 Å. In the ninth Bi site, Bi(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 BiO6 octahedra that share corners with two equivalent Bi(12)O4 tetrahedra,  an edgeedge with one Bi(7)O6 octahedra, edges with two equivalent Bi(10)O6 octahedra, and edges with two equivalent Bi(11)O6 octahedra. The Bi(9)-O(17) bond length is 2.11 Å. The Bi(9)-O(18) bond length is 2.23 Å. The Bi(9)-O(19) bond length is 2.23 Å. The Bi(9)-O(21) bond length is 2.19 Å. The Bi(9)-O(22) bond length is 2.18 Å. The Bi(9)-O(23) bond length is 2.13 Å. In the tenth Bi site, Bi(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 distorted BiO6 octahedra that share corners with two equivalent Bi(12)O4 tetrahedra,  an edgeedge with one Bi(7)O6 octahedra, edges with two equivalent Bi(11)O6 octahedra, and edges with two equivalent Bi(9)O6 octahedra. The Bi(10)-O(13) bond length is 2.40 Å. The Bi(10)-O(17) bond length is 2.42 Å. The Bi(10)-O(19) bond length is 2.45 Å. The Bi(10)-O(21) bond length is 2.42 Å. The Bi(10)-O(23) bond length is 2.37 Å. The Bi(10)-O(24) bond length is 2.34 Å. In the eleventh Bi site, Bi(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 distorted BiO6 octahedra that share corners with two equivalent Bi(12)O4 tetrahedra,  an edgeedge with one Bi(7)O6 octahedra, edges with two equivalent Bi(10)O6 octahedra, and edges with two equivalent Bi(9)O6 octahedra. The Bi(11)-O(13) bond length is 2.36 Å. The Bi(11)-O(17) bond length is 2.42 Å. The Bi(11)-O(18) bond length is 2.45 Å. The Bi(11)-O(22) bond length is 2.39 Å. The Bi(11)-O(23) bond length is 2.33 Å. The Bi(11)-O(24) bond length is 2.41 Å. In the twelfth Bi site, Bi(12) is bonded to one O(21), one O(22), one O(24), and one O(7) atom to form corner-sharing BiO4 tetrahedra. The corner-sharing octahedral tilt angles range from 45-62°. The Bi(12)-O(21) bond length is 2.22 Å. The Bi(12)-O(22) bond length is 2.25 Å. The Bi(12)-O(24) bond length is 2.11 Å. The Bi(12)-O(7) bond length is 2.42 Å. There are twenty-four inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to one Bi(4) and one Bi(6) atom. In the second O site, O(2) is bonded in a water-like geometry to one Bi(1) and one Bi(6) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Bi(1), one Bi(4), and one Bi(6) atom. In the fourth O site, O(4) is bonded in a water-like geometry to one Bi(1) and one Bi(4) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Bi(2), one Bi(3), and one Bi(8) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Bi(1), one Bi(3), and one Bi(4) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Bi(1), one Bi(12), one Bi(4), and one Bi(6) atom. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Bi(1), one Bi(3), and one Bi(6) atom. In the ninth O site, O(9) is bonded in a distorted trigonal non-coplanar geometry to one Bi(2), one Bi(3), and one Bi(5) atom. In the tenth O site, O(10) is bonded in a trigonal non-coplanar geometry to one Bi(2), one Bi(5), and one Bi(8) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal non-coplanar geometry to one Bi(3), one Bi(5), and one Bi(8) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal non-coplanar geometry to one Bi(3), one Bi(4), and one Bi(6) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal non-coplanar geometry to one Bi(10), one Bi(11), and one Bi(7) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal non-coplanar geometry to one Bi(5), one Bi(7), and one Bi(8) atom. In the fifteenth O site, O(15) is bonded in a trigonal non-coplanar geometry to one Bi(2), one Bi(5), and one Bi(8) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal non-coplanar geometry to one Bi(2), one Bi(5), and one Bi(7) atom. In the seventeenth O site, O(17) is bonded in a distorted trigonal non-coplanar geometry to one Bi(10), one Bi(11), and one Bi(9) atom. In the eighteenth O site, O(18) is bonded in a distorted trigonal non-coplanar geometry to one Bi(11), one Bi(7), and one Bi(9) atom. In the nineteenth O site, O(19) is bonded in a distorted trigonal non-coplanar geometry to one Bi(10), one Bi(7), and one Bi(9) atom. In the twentieth O site, O(20) is bonded in a distorted trigonal non-coplanar geometry to one Bi(2), one Bi(7), and one Bi(8) atom. In the twenty-first O site, O(21) is bonded in a distorted trigonal planar geometry to one Bi(10), one Bi(12), and one Bi(9) atom. In the twenty-second O site, O(22) is bonded in a distorted trigonal planar geometry to one Bi(11), one Bi(12), and one Bi(9) atom. In the twenty-third O site, O(23) is bonded in a trigonal non-coplanar geometry to one Bi(10), one Bi(11), and one Bi(9) atom. In the twenty-fourth O site, O(24) is bonded in a distorted trigonal planar geometry to one Bi(10), one Bi(11), and one Bi(12) atom.