The crystal structure described by Sc2O3 crystallizes in the orthorhombic Pna2_1 space group. There are four inequivalent Sc sites. In the first Sc site, Sc(1) is bonded to one O(1), one O(5), two equivalent O(2), and two equivalent O(6) atoms to form ScO6 octahedra that share corners with two equivalent Sc(4)O6 octahedra, corners with three equivalent Sc(2)O4 tetrahedra, edges with two equivalent Sc(1)O6 octahedra, edges with two equivalent Sc(4)O6 octahedra, and edges with three equivalent Sc(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 12-49°. In the second Sc site, Sc(2) is bonded to one O(1), one O(6), and two equivalent O(3) atoms to form ScO4 tetrahedra that share  a cornercorner with one Sc(4)O6 octahedra, corners with three equivalent Sc(1)O6 octahedra, corners with four equivalent Sc(3)O6 octahedra, and corners with two equivalent Sc(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 55-69°. In the third Sc site, Sc(3) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form distorted ScO6 octahedra that share corners with four equivalent Sc(4)O6 octahedra, corners with four equivalent Sc(2)O4 tetrahedra,  an edgeedge with one Sc(4)O6 octahedra, and edges with three equivalent Sc(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-57°. In the fourth Sc site, Sc(4) is bonded to one O(1), one O(5), two equivalent O(2), and two equivalent O(4) atoms to form distorted ScO6 octahedra that share corners with two equivalent Sc(1)O6 octahedra, corners with four equivalent Sc(3)O6 octahedra,  a cornercorner with one Sc(2)O4 tetrahedra,  an edgeedge with one Sc(3)O6 octahedra, edges with two equivalent Sc(1)O6 octahedra, and edges with two equivalent Sc(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-57°. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Sc(1), one Sc(2), one Sc(3), and one Sc(4) atom to form OSc4 tetrahedra that share  a cornercorner with one O(2)Sc5 square pyramid, corners with two equivalent O(6)Sc4 tetrahedra, edges with two equivalent O(2)Sc5 square pyramids, and  an edgeedge with one O(6)Sc4 tetrahedra. In the second O site, O(2) is bonded to one Sc(3), two equivalent Sc(1), and two equivalent Sc(4) atoms to form OSc5 square pyramids that share  a cornercorner with one O(1)Sc4 tetrahedra,  a cornercorner with one O(6)Sc4 tetrahedra, edges with two equivalent O(2)Sc5 square pyramids, edges with two equivalent O(1)Sc4 tetrahedra, and edges with two equivalent O(6)Sc4 tetrahedra. In the third O site, O(3) is bonded in a trigonal planar geometry to one Sc(3) and two equivalent Sc(2) atoms. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Sc(3) and two equivalent Sc(4) atoms. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Sc(1), one Sc(3), and one Sc(4) atom. In the sixth O site, O(6) is bonded to one Sc(2), one Sc(3), and two equivalent Sc(1) atoms to form OSc4 tetrahedra that share  a cornercorner with one O(2)Sc5 square pyramid, corners with two equivalent O(1)Sc4 tetrahedra, corners with two equivalent O(6)Sc4 tetrahedra, edges with two equivalent O(2)Sc5 square pyramids, and  an edgeedge with one O(1)Sc4 tetrahedra. is represented by the CIF file [CIF]
data_Sc2O3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.458
_cell_length_b   9.335
_cell_length_c   9.941
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   506.464
_cell_formula_units_Z   8
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Sc  Sc0  1  0.180  0.162  0.870  1.0
  Sc  Sc1  1  0.177  0.853  0.058  1.0
  Sc  Sc2  1  0.171  0.530  0.860  1.0
  Sc  Sc3  1  0.185  0.845  0.647  1.0
  Sc  Sc4  1  0.323  0.353  0.558  1.0
  Sc  Sc5  1  0.329  0.030  0.360  1.0
  Sc  Sc6  1  0.315  0.345  0.147  1.0
  Sc  Sc7  1  0.320  0.662  0.370  1.0
  Sc  Sc8  1  0.685  0.655  0.647  1.0
  Sc  Sc9  1  0.671  0.970  0.860  1.0
  Sc  Sc10  1  0.680  0.338  0.870  1.0
  Sc  Sc11  1  0.677  0.647  0.058  1.0
  Sc  Sc12  1  0.823  0.147  0.558  1.0
  Sc  Sc13  1  0.815  0.155  0.147  1.0
  Sc  Sc14  1  0.829  0.470  0.360  1.0
  Sc  Sc15  1  0.820  0.838  0.370  1.0
  O  O16  1  0.970  0.017  0.994  1.0
  O  O17  1  0.009  0.325  0.990  1.0
  O  O18  1  0.030  0.983  0.494  1.0
  O  O19  1  0.023  0.672  0.002  1.0
  O  O20  1  0.977  0.328  0.502  1.0
  O  O21  1  0.991  0.675  0.490  1.0
  O  O22  1  0.159  0.166  0.234  1.0
  O  O23  1  0.166  0.493  0.271  1.0
  O  O24  1  0.162  0.838  0.260  1.0
  O  O25  1  0.338  0.338  0.760  1.0
  O  O26  1  0.334  0.993  0.771  1.0
  O  O27  1  0.341  0.666  0.734  1.0
  O  O28  1  0.509  0.175  0.990  1.0
  O  O29  1  0.477  0.172  0.502  1.0
  O  O30  1  0.523  0.828  0.002  1.0
  O  O31  1  0.491  0.825  0.490  1.0
  O  O32  1  0.530  0.517  0.494  1.0
  O  O33  1  0.470  0.483  0.994  1.0
  O  O34  1  0.662  0.662  0.260  1.0
  O  O35  1  0.666  0.007  0.271  1.0
  O  O36  1  0.659  0.334  0.234  1.0
  O  O37  1  0.838  0.162  0.760  1.0
  O  O38  1  0.834  0.507  0.771  1.0
  O  O39  1  0.841  0.834  0.734  1.0
[/CIF]
.
The crystal structure described by Sc2O3 crystallizes in the orthorhombic Pna2_1 space group. There are four inequivalent Sc sites. In the first Sc site, Sc(1) is bonded to one O(1), one O(5), two equivalent O(2), and two equivalent O(6) atoms to form ScO6 octahedra that share corners with two equivalent Sc(4)O6 octahedra, corners with three equivalent Sc(2)O4 tetrahedra, edges with two equivalent Sc(1)O6 octahedra, edges with two equivalent Sc(4)O6 octahedra, and edges with three equivalent Sc(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 12-49°. In the second Sc site, Sc(2) is bonded to one O(1), one O(6), and two equivalent O(3) atoms to form ScO4 tetrahedra that share  a cornercorner with one Sc(4)O6 octahedra, corners with three equivalent Sc(1)O6 octahedra, corners with four equivalent Sc(3)O6 octahedra, and corners with two equivalent Sc(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 55-69°. In the third Sc site, Sc(3) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form distorted ScO6 octahedra that share corners with four equivalent Sc(4)O6 octahedra, corners with four equivalent Sc(2)O4 tetrahedra,  an edgeedge with one Sc(4)O6 octahedra, and edges with three equivalent Sc(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-57°. In the fourth Sc site, Sc(4) is bonded to one O(1), one O(5), two equivalent O(2), and two equivalent O(4) atoms to form distorted ScO6 octahedra that share corners with two equivalent Sc(1)O6 octahedra, corners with four equivalent Sc(3)O6 octahedra,  a cornercorner with one Sc(2)O4 tetrahedra,  an edgeedge with one Sc(3)O6 octahedra, edges with two equivalent Sc(1)O6 octahedra, and edges with two equivalent Sc(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-57°. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Sc(1), one Sc(2), one Sc(3), and one Sc(4) atom to form OSc4 tetrahedra that share  a cornercorner with one O(2)Sc5 square pyramid, corners with two equivalent O(6)Sc4 tetrahedra, edges with two equivalent O(2)Sc5 square pyramids, and  an edgeedge with one O(6)Sc4 tetrahedra. In the second O site, O(2) is bonded to one Sc(3), two equivalent Sc(1), and two equivalent Sc(4) atoms to form OSc5 square pyramids that share  a cornercorner with one O(1)Sc4 tetrahedra,  a cornercorner with one O(6)Sc4 tetrahedra, edges with two equivalent O(2)Sc5 square pyramids, edges with two equivalent O(1)Sc4 tetrahedra, and edges with two equivalent O(6)Sc4 tetrahedra. In the third O site, O(3) is bonded in a trigonal planar geometry to one Sc(3) and two equivalent Sc(2) atoms. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Sc(3) and two equivalent Sc(4) atoms. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Sc(1), one Sc(3), and one Sc(4) atom. In the sixth O site, O(6) is bonded to one Sc(2), one Sc(3), and two equivalent Sc(1) atoms to form OSc4 tetrahedra that share  a cornercorner with one O(2)Sc5 square pyramid, corners with two equivalent O(1)Sc4 tetrahedra, corners with two equivalent O(6)Sc4 tetrahedra, edges with two equivalent O(2)Sc5 square pyramids, and  an edgeedge with one O(1)Sc4 tetrahedra. is represented by the CIF file [CIF]
data_Sc2O3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.458
_cell_length_b   9.335
_cell_length_c   9.941
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   506.464
_cell_formula_units_Z   8
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Sc  Sc0  1  0.180  0.162  0.870  1.0
  Sc  Sc1  1  0.177  0.853  0.058  1.0
  Sc  Sc2  1  0.171  0.530  0.860  1.0
  Sc  Sc3  1  0.185  0.845  0.647  1.0
  Sc  Sc4  1  0.323  0.353  0.558  1.0
  Sc  Sc5  1  0.329  0.030  0.360  1.0
  Sc  Sc6  1  0.315  0.345  0.147  1.0
  Sc  Sc7  1  0.320  0.662  0.370  1.0
  Sc  Sc8  1  0.685  0.655  0.647  1.0
  Sc  Sc9  1  0.671  0.970  0.860  1.0
  Sc  Sc10  1  0.680  0.338  0.870  1.0
  Sc  Sc11  1  0.677  0.647  0.058  1.0
  Sc  Sc12  1  0.823  0.147  0.558  1.0
  Sc  Sc13  1  0.815  0.155  0.147  1.0
  Sc  Sc14  1  0.829  0.470  0.360  1.0
  Sc  Sc15  1  0.820  0.838  0.370  1.0
  O  O16  1  0.970  0.017  0.994  1.0
  O  O17  1  0.009  0.325  0.990  1.0
  O  O18  1  0.030  0.983  0.494  1.0
  O  O19  1  0.023  0.672  0.002  1.0
  O  O20  1  0.977  0.328  0.502  1.0
  O  O21  1  0.991  0.675  0.490  1.0
  O  O22  1  0.159  0.166  0.234  1.0
  O  O23  1  0.166  0.493  0.271  1.0
  O  O24  1  0.162  0.838  0.260  1.0
  O  O25  1  0.338  0.338  0.760  1.0
  O  O26  1  0.334  0.993  0.771  1.0
  O  O27  1  0.341  0.666  0.734  1.0
  O  O28  1  0.509  0.175  0.990  1.0
  O  O29  1  0.477  0.172  0.502  1.0
  O  O30  1  0.523  0.828  0.002  1.0
  O  O31  1  0.491  0.825  0.490  1.0
  O  O32  1  0.530  0.517  0.494  1.0
  O  O33  1  0.470  0.483  0.994  1.0
  O  O34  1  0.662  0.662  0.260  1.0
  O  O35  1  0.666  0.007  0.271  1.0
  O  O36  1  0.659  0.334  0.234  1.0
  O  O37  1  0.838  0.162  0.760  1.0
  O  O38  1  0.834  0.507  0.771  1.0
  O  O39  1  0.841  0.834  0.734  1.0
[/CIF]
.