The structure described by Gd2Se2O crystallizes in the orthorhombic Pnma space group. There are two inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 3-coordinate geometry to two equivalent Se(1), three equivalent Se(2), and three equivalent O(1) atoms. In the second Gd site, Gd(2) is bonded to two equivalent Se(2), three equivalent Se(1), and one O(1) atom to form a mixture of distorted corner and edge-sharing GdSe5O octahedra. The corner-sharing octahedral tilt angles are 63°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to two equivalent Gd(1) and three equivalent Gd(2) atoms. In the second Se site, Se(2) is bonded to two equivalent Gd(2) and three equivalent Gd(1) atoms to form distorted SeGd5 trigonal bipyramids that share corners with five equivalent O(1)Gd4 tetrahedra, edges with three equivalent O(1)Gd4 tetrahedra, and edges with four equivalent Se(2)Gd5 trigonal bipyramids. O(1) is bonded to one Gd(2) and three equivalent Gd(1) atoms to form OGd4 tetrahedra that share corners with two equivalent O(1)Gd4 tetrahedra, corners with five equivalent Se(2)Gd5 trigonal bipyramids, edges with two equivalent O(1)Gd4 tetrahedra, and edges with three equivalent Se(2)Gd5 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Gd2Se2O
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.965
_cell_length_b   7.073
_cell_length_c   16.199
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   454.277
_cell_formula_units_Z   4
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
  Gd  Gd0  1  0.250  0.698  0.039  1.0
  Gd  Gd1  1  0.750  0.741  0.839  1.0
  Gd  Gd2  1  0.250  0.241  0.661  1.0
  Gd  Gd3  1  0.250  0.259  0.161  1.0
  Gd  Gd4  1  0.250  0.802  0.539  1.0
  Gd  Gd5  1  0.750  0.759  0.339  1.0
  Gd  Gd6  1  0.750  0.302  0.961  1.0
  Gd  Gd7  1  0.750  0.198  0.461  1.0
  Se  Se8  1  0.750  0.551  0.180  1.0
  Se  Se9  1  0.750  0.489  0.599  1.0
  Se  Se10  1  0.250  0.449  0.820  1.0
  Se  Se11  1  0.750  0.011  0.099  1.0
  Se  Se12  1  0.250  0.051  0.320  1.0
  Se  Se13  1  0.250  0.989  0.901  1.0
  Se  Se14  1  0.750  0.949  0.680  1.0
  Se  Se15  1  0.250  0.511  0.401  1.0
  O  O16  1  0.250  0.128  0.531  1.0
  O  O17  1  0.750  0.872  0.469  1.0
  O  O18  1  0.750  0.628  0.969  1.0
  O  O19  1  0.250  0.372  0.031  1.0
[/CIF]
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The structure described by Gd2Se2O crystallizes in the orthorhombic Pnma space group. There are two inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 3-coordinate geometry to two equivalent Se(1), three equivalent Se(2), and three equivalent O(1) atoms. In the second Gd site, Gd(2) is bonded to two equivalent Se(2), three equivalent Se(1), and one O(1) atom to form a mixture of distorted corner and edge-sharing GdSe5O octahedra. The corner-sharing octahedral tilt angles are 63°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to two equivalent Gd(1) and three equivalent Gd(2) atoms. In the second Se site, Se(2) is bonded to two equivalent Gd(2) and three equivalent Gd(1) atoms to form distorted SeGd5 trigonal bipyramids that share corners with five equivalent O(1)Gd4 tetrahedra, edges with three equivalent O(1)Gd4 tetrahedra, and edges with four equivalent Se(2)Gd5 trigonal bipyramids. O(1) is bonded to one Gd(2) and three equivalent Gd(1) atoms to form OGd4 tetrahedra that share corners with two equivalent O(1)Gd4 tetrahedra, corners with five equivalent Se(2)Gd5 trigonal bipyramids, edges with two equivalent O(1)Gd4 tetrahedra, and edges with three equivalent Se(2)Gd5 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Gd2Se2O
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.965
_cell_length_b   7.073
_cell_length_c   16.199
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   454.277
_cell_formula_units_Z   4
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
  Gd  Gd0  1  0.250  0.698  0.039  1.0
  Gd  Gd1  1  0.750  0.741  0.839  1.0
  Gd  Gd2  1  0.250  0.241  0.661  1.0
  Gd  Gd3  1  0.250  0.259  0.161  1.0
  Gd  Gd4  1  0.250  0.802  0.539  1.0
  Gd  Gd5  1  0.750  0.759  0.339  1.0
  Gd  Gd6  1  0.750  0.302  0.961  1.0
  Gd  Gd7  1  0.750  0.198  0.461  1.0
  Se  Se8  1  0.750  0.551  0.180  1.0
  Se  Se9  1  0.750  0.489  0.599  1.0
  Se  Se10  1  0.250  0.449  0.820  1.0
  Se  Se11  1  0.750  0.011  0.099  1.0
  Se  Se12  1  0.250  0.051  0.320  1.0
  Se  Se13  1  0.250  0.989  0.901  1.0
  Se  Se14  1  0.750  0.949  0.680  1.0
  Se  Se15  1  0.250  0.511  0.401  1.0
  O  O16  1  0.250  0.128  0.531  1.0
  O  O17  1  0.750  0.872  0.469  1.0
  O  O18  1  0.750  0.628  0.969  1.0
  O  O19  1  0.250  0.372  0.031  1.0
[/CIF]
.