SbO2 crystallizes in the monoclinic Cm space group. There are twelve inequivalent Sb sites. In the first Sb site, Sb(1) is bonded to one O(1), one O(2), one O(3), one O(6), and one O(8) atom to form distorted SbO5 square pyramids that share  a cornercorner with one Sb(2)O6 octahedra,  a cornercorner with one Sb(1)O5 square pyramid,  a cornercorner with one Sb(5)O4 trigonal pyramid,  an edgeedge with one Sb(11)O6 octahedra, and  an edgeedge with one Sb(1)O5 square pyramid. The corner-sharing octahedral tilt angles are 74°. In the second Sb site, Sb(2) is bonded to one O(4), one O(9), two equivalent O(5), and two equivalent O(6) atoms to form SbO6 octahedra that share corners with two equivalent Sb(1)O5 square pyramids, corners with three equivalent Sb(5)O4 trigonal pyramids, and edges with two equivalent Sb(4)O6 octahedra. In the third Sb site, Sb(3) is bonded in a distorted T-shaped geometry to one O(7) and two equivalent O(10) atoms. In the fourth Sb site, Sb(4) is bonded to one O(11), one O(12), one O(14), one O(5), one O(7), and one O(9) atom to form SbO6 octahedra that share  a cornercorner with one Sb(5)O4 trigonal pyramid,  an edgeedge with one Sb(2)O6 octahedra, and edges with two equivalent Sb(4)O6 octahedra. In the fifth Sb site, Sb(5) is bonded to one O(14), one O(4), and two equivalent O(6) atoms to form SbO4 trigonal pyramids that share corners with two equivalent Sb(4)O6 octahedra, corners with three equivalent Sb(2)O6 octahedra, and corners with two equivalent Sb(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 26-55°. In the sixth Sb site, Sb(6) is bonded in a 3-coordinate geometry to one O(13) and two equivalent O(17) atoms. In the seventh Sb site, Sb(7) is bonded to one O(10), one O(13), one O(15), one O(16), one O(18), and one O(20) atom to form edge-sharing SbO6 octahedra. In the eighth Sb site, Sb(8) is bonded in a distorted trigonal non-coplanar geometry to one O(20) and two equivalent O(12) atoms. In the ninth Sb site, Sb(9) is bonded to one O(17), one O(19), one O(21), one O(22), one O(23), and one O(24) atom to form edge-sharing SbO6 octahedra. In the tenth Sb site, Sb(10) is bonded in a distorted trigonal non-coplanar geometry to one O(24) and two equivalent O(18) atoms. In the eleventh Sb site, Sb(11) is bonded to one O(22), one O(3), two equivalent O(1), and two equivalent O(23) atoms to form SbO6 octahedra that share edges with two equivalent Sb(9)O6 octahedra and edges with two equivalent Sb(1)O5 square pyramids. In the twelfth Sb site, Sb(12) is bonded in a 5-coordinate geometry to one O(8), two equivalent O(1), and two equivalent O(23) atoms. There are twenty-four inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Sb(1), one Sb(11), and one Sb(12) atom. In the second O site, O(2) is bonded in a water-like geometry to two equivalent Sb(1) atoms. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Sb(11) and two equivalent Sb(1) atoms. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Sb(2) and one Sb(5) atom. In the fifth O site, O(5) is bonded in a water-like geometry to one Sb(2) and one Sb(4) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Sb(1), one Sb(2), and one Sb(5) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Sb(3) and two equivalent Sb(4) atoms. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Sb(12) and two equivalent Sb(1) atoms. In the ninth O site, O(9) is bonded in a distorted T-shaped geometry to one Sb(2) and two equivalent Sb(4) atoms. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to one Sb(3) and one Sb(7) atom. In the eleventh O site, O(11) is bonded in a water-like geometry to two equivalent Sb(4) atoms. In the twelfth O site, O(12) is bonded in a bent 120 degrees geometry to one Sb(4) and one Sb(8) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal planar geometry to one Sb(6) and two equivalent Sb(7) atoms. In the fourteenth O site, O(14) is bonded in a trigonal planar geometry to one Sb(5) and two equivalent Sb(4) atoms. In the fifteenth O site, O(15) is bonded in a water-like geometry to two equivalent Sb(7) atoms. In the sixteenth O site, O(16) is bonded in a water-like geometry to two equivalent Sb(7) atoms. In the seventeenth O site, O(17) is bonded in a distorted bent 120 degrees geometry to one Sb(6) and one Sb(9) atom. In the eighteenth O site, O(18) is bonded in a distorted bent 120 degrees geometry to one Sb(10) and one Sb(7) atom. In the nineteenth O site, O(19) is bonded in a water-like geometry to two equivalent Sb(9) atoms. In the twentieth O site, O(20) is bonded in a distorted trigonal planar geometry to one Sb(8) and two equivalent Sb(7) atoms. In the twenty-first O site, O(21) is bonded in an L-shaped geometry to two equivalent Sb(9) atoms. In the twenty-second O site, O(22) is bonded in a distorted trigonal non-coplanar geometry to one Sb(11) and two equivalent Sb(9) atoms. In the twenty-third O site, O(23) is bonded in a distorted trigonal planar geometry to one Sb(11), one Sb(12), and one Sb(9) atom. In the twenty-fourth O site, O(24) is bonded in a trigonal planar geometry to one Sb(10) and two equivalent Sb(9) atoms.
SbO2 crystallizes in the monoclinic Cm space group. There are twelve inequivalent Sb sites. In the first Sb site, Sb(1) is bonded to one O(1), one O(2), one O(3), one O(6), and one O(8) atom to form distorted SbO5 square pyramids that share  a cornercorner with one Sb(2)O6 octahedra,  a cornercorner with one Sb(1)O5 square pyramid,  a cornercorner with one Sb(5)O4 trigonal pyramid,  an edgeedge with one Sb(11)O6 octahedra, and  an edgeedge with one Sb(1)O5 square pyramid. The corner-sharing octahedral tilt angles are 74°. The Sb(1)-O(1) bond length is 2.25 Å. The Sb(1)-O(2) bond length is 2.00 Å. The Sb(1)-O(3) bond length is 2.24 Å. The Sb(1)-O(6) bond length is 2.47 Å. The Sb(1)-O(8) bond length is 2.58 Å. In the second Sb site, Sb(2) is bonded to one O(4), one O(9), two equivalent O(5), and two equivalent O(6) atoms to form SbO6 octahedra that share corners with two equivalent Sb(1)O5 square pyramids, corners with three equivalent Sb(5)O4 trigonal pyramids, and edges with two equivalent Sb(4)O6 octahedra. The Sb(2)-O(4) bond length is 1.96 Å. The Sb(2)-O(9) bond length is 2.19 Å. Both Sb(2)-O(5) bond lengths are 2.01 Å. Both Sb(2)-O(6) bond lengths are 2.03 Å. In the third Sb site, Sb(3) is bonded in a distorted T-shaped geometry to one O(7) and two equivalent O(10) atoms. The Sb(3)-O(7) bond length is 2.11 Å. Both Sb(3)-O(10) bond lengths are 1.99 Å. In the fourth Sb site, Sb(4) is bonded to one O(11), one O(12), one O(14), one O(5), one O(7), and one O(9) atom to form SbO6 octahedra that share  a cornercorner with one Sb(5)O4 trigonal pyramid,  an edgeedge with one Sb(2)O6 octahedra, and edges with two equivalent Sb(4)O6 octahedra. The Sb(4)-O(11) bond length is 2.00 Å. The Sb(4)-O(12) bond length is 1.97 Å. The Sb(4)-O(14) bond length is 2.13 Å. The Sb(4)-O(5) bond length is 1.95 Å. The Sb(4)-O(7) bond length is 2.13 Å. The Sb(4)-O(9) bond length is 2.11 Å. In the fifth Sb site, Sb(5) is bonded to one O(14), one O(4), and two equivalent O(6) atoms to form SbO4 trigonal pyramids that share corners with two equivalent Sb(4)O6 octahedra, corners with three equivalent Sb(2)O6 octahedra, and corners with two equivalent Sb(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 26-55°. The Sb(5)-O(14) bond length is 2.15 Å. The Sb(5)-O(4) bond length is 2.12 Å. Both Sb(5)-O(6) bond lengths are 2.11 Å. In the sixth Sb site, Sb(6) is bonded in a 3-coordinate geometry to one O(13) and two equivalent O(17) atoms. The Sb(6)-O(13) bond length is 2.12 Å. Both Sb(6)-O(17) bond lengths are 1.99 Å. In the seventh Sb site, Sb(7) is bonded to one O(10), one O(13), one O(15), one O(16), one O(18), and one O(20) atom to form edge-sharing SbO6 octahedra. The Sb(7)-O(10) bond length is 1.99 Å. The Sb(7)-O(13) bond length is 2.12 Å. The Sb(7)-O(15) bond length is 2.02 Å. The Sb(7)-O(16) bond length is 2.02 Å. The Sb(7)-O(18) bond length is 2.00 Å. The Sb(7)-O(20) bond length is 2.15 Å. In the eighth Sb site, Sb(8) is bonded in a distorted trigonal non-coplanar geometry to one O(20) and two equivalent O(12) atoms. The Sb(8)-O(20) bond length is 2.17 Å. Both Sb(8)-O(12) bond lengths are 2.00 Å. In the ninth Sb site, Sb(9) is bonded to one O(17), one O(19), one O(21), one O(22), one O(23), and one O(24) atom to form edge-sharing SbO6 octahedra. The Sb(9)-O(17) bond length is 1.98 Å. The Sb(9)-O(19) bond length is 1.99 Å. The Sb(9)-O(21) bond length is 2.04 Å. The Sb(9)-O(22) bond length is 2.14 Å. The Sb(9)-O(23) bond length is 2.03 Å. The Sb(9)-O(24) bond length is 2.16 Å. In the tenth Sb site, Sb(10) is bonded in a distorted trigonal non-coplanar geometry to one O(24) and two equivalent O(18) atoms. The Sb(10)-O(24) bond length is 2.16 Å. Both Sb(10)-O(18) bond lengths are 1.99 Å. In the eleventh Sb site, Sb(11) is bonded to one O(22), one O(3), two equivalent O(1), and two equivalent O(23) atoms to form SbO6 octahedra that share edges with two equivalent Sb(9)O6 octahedra and edges with two equivalent Sb(1)O5 square pyramids. The Sb(11)-O(22) bond length is 2.08 Å. The Sb(11)-O(3) bond length is 2.04 Å. Both Sb(11)-O(1) bond lengths are 2.04 Å. Both Sb(11)-O(23) bond lengths are 2.02 Å. In the twelfth Sb site, Sb(12) is bonded in a 5-coordinate geometry to one O(8), two equivalent O(1), and two equivalent O(23) atoms. The Sb(12)-O(8) bond length is 1.91 Å. Both Sb(12)-O(1) bond lengths are 2.28 Å. Both Sb(12)-O(23) bond lengths are 2.67 Å. There are twenty-four inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Sb(1), one Sb(11), and one Sb(12) atom. In the second O site, O(2) is bonded in a water-like geometry to two equivalent Sb(1) atoms. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Sb(11) and two equivalent Sb(1) atoms. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Sb(2) and one Sb(5) atom. In the fifth O site, O(5) is bonded in a water-like geometry to one Sb(2) and one Sb(4) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Sb(1), one Sb(2), and one Sb(5) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Sb(3) and two equivalent Sb(4) atoms. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Sb(12) and two equivalent Sb(1) atoms. In the ninth O site, O(9) is bonded in a distorted T-shaped geometry to one Sb(2) and two equivalent Sb(4) atoms. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to one Sb(3) and one Sb(7) atom. In the eleventh O site, O(11) is bonded in a water-like geometry to two equivalent Sb(4) atoms. In the twelfth O site, O(12) is bonded in a bent 120 degrees geometry to one Sb(4) and one Sb(8) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal planar geometry to one Sb(6) and two equivalent Sb(7) atoms. In the fourteenth O site, O(14) is bonded in a trigonal planar geometry to one Sb(5) and two equivalent Sb(4) atoms. In the fifteenth O site, O(15) is bonded in a water-like geometry to two equivalent Sb(7) atoms. In the sixteenth O site, O(16) is bonded in a water-like geometry to two equivalent Sb(7) atoms. In the seventeenth O site, O(17) is bonded in a distorted bent 120 degrees geometry to one Sb(6) and one Sb(9) atom. In the eighteenth O site, O(18) is bonded in a distorted bent 120 degrees geometry to one Sb(10) and one Sb(7) atom. In the nineteenth O site, O(19) is bonded in a water-like geometry to two equivalent Sb(9) atoms. In the twentieth O site, O(20) is bonded in a distorted trigonal planar geometry to one Sb(8) and two equivalent Sb(7) atoms. In the twenty-first O site, O(21) is bonded in an L-shaped geometry to two equivalent Sb(9) atoms. In the twenty-second O site, O(22) is bonded in a distorted trigonal non-coplanar geometry to one Sb(11) and two equivalent Sb(9) atoms. In the twenty-third O site, O(23) is bonded in a distorted trigonal planar geometry to one Sb(11), one Sb(12), and one Sb(9) atom. In the twenty-fourth O site, O(24) is bonded in a trigonal planar geometry to one Sb(10) and two equivalent Sb(9) atoms.