The material structure described by Cs2As2Se6O crystallizes in the monoclinic C2/c space group. Cs(1) is bonded in a 1-coordinate geometry to two equivalent Se(1), two equivalent Se(2), and one O(1) atom. As(1) is bonded in a distorted T-shaped geometry to one Se(1), one Se(2), and one Se(3) atom. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Cs(1), one As(1), and one Se(2) atom to form distorted SeCs2AsSe trigonal pyramids that share corners with two equivalent Se(1)Cs2AsSe trigonal pyramids, corners with two equivalent O(1)Cs2Se2 trigonal pyramids, corners with three equivalent Se(2)Cs2AsSe trigonal pyramids, and  an edgeedge with one Se(2)Cs2AsSe trigonal pyramid. In the second Se site, Se(2) is bonded to two equivalent Cs(1), one As(1), and one Se(1) atom to form distorted SeCs2AsSe trigonal pyramids that share corners with two equivalent Se(2)Cs2AsSe trigonal pyramids, corners with two equivalent O(1)Cs2Se2 trigonal pyramids, corners with three equivalent Se(1)Cs2AsSe trigonal pyramids, and  an edgeedge with one Se(1)Cs2AsSe trigonal pyramid. In the third Se site, Se(3) is bonded in a 2-coordinate geometry to one As(1) and one O(1) atom. O(1) is bonded to two equivalent Cs(1) and two equivalent Se(3) atoms to form distorted OCs2Se2 trigonal pyramids that share corners with four equivalent Se(1)Cs2AsSe trigonal pyramids and corners with four equivalent Se(2)Cs2AsSe trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cs2As2Se6O
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.861
_cell_length_b   11.861
_cell_length_c   12.492
_cell_angle_alpha   61.471
_cell_angle_beta   61.471
_cell_angle_gamma   28.256
_symmetry_Int_Tables_number   1
_cell_volume   724.090
_cell_formula_units_Z   2
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
  Cs  Cs0  1  0.581  0.573  0.553  1.0
  Cs  Cs1  1  0.427  0.419  0.947  1.0
  Cs  Cs2  1  0.419  0.427  0.447  1.0
  Cs  Cs3  1  0.573  0.581  0.053  1.0
  As  As4  1  0.148  0.211  0.215  1.0
  As  As5  1  0.789  0.852  0.285  1.0
  As  As6  1  0.852  0.789  0.785  1.0
  As  As7  1  0.211  0.148  0.715  1.0
  Se  Se8  1  0.737  0.638  0.187  1.0
  Se  Se9  1  0.362  0.263  0.313  1.0
  Se  Se10  1  0.263  0.362  0.813  1.0
  Se  Se11  1  0.638  0.737  0.687  1.0
  Se  Se12  1  0.193  0.195  0.397  1.0
  Se  Se13  1  0.805  0.807  0.103  1.0
  Se  Se14  1  0.807  0.805  0.603  1.0
  Se  Se15  1  0.195  0.193  0.897  1.0
  Se  Se16  1  0.019  0.098  0.319  1.0
  Se  Se17  1  0.902  0.981  0.181  1.0
  Se  Se18  1  0.981  0.902  0.681  1.0
  Se  Se19  1  0.098  0.019  0.819  1.0
  O  O20  1  0.919  0.081  0.750  1.0
  O  O21  1  0.081  0.919  0.250  1.0
[/CIF]
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The material structure described by Cs2As2Se6O crystallizes in the monoclinic C2/c space group. Cs(1) is bonded in a 1-coordinate geometry to two equivalent Se(1), two equivalent Se(2), and one O(1) atom. As(1) is bonded in a distorted T-shaped geometry to one Se(1), one Se(2), and one Se(3) atom. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Cs(1), one As(1), and one Se(2) atom to form distorted SeCs2AsSe trigonal pyramids that share corners with two equivalent Se(1)Cs2AsSe trigonal pyramids, corners with two equivalent O(1)Cs2Se2 trigonal pyramids, corners with three equivalent Se(2)Cs2AsSe trigonal pyramids, and  an edgeedge with one Se(2)Cs2AsSe trigonal pyramid. In the second Se site, Se(2) is bonded to two equivalent Cs(1), one As(1), and one Se(1) atom to form distorted SeCs2AsSe trigonal pyramids that share corners with two equivalent Se(2)Cs2AsSe trigonal pyramids, corners with two equivalent O(1)Cs2Se2 trigonal pyramids, corners with three equivalent Se(1)Cs2AsSe trigonal pyramids, and  an edgeedge with one Se(1)Cs2AsSe trigonal pyramid. In the third Se site, Se(3) is bonded in a 2-coordinate geometry to one As(1) and one O(1) atom. O(1) is bonded to two equivalent Cs(1) and two equivalent Se(3) atoms to form distorted OCs2Se2 trigonal pyramids that share corners with four equivalent Se(1)Cs2AsSe trigonal pyramids and corners with four equivalent Se(2)Cs2AsSe trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cs2As2Se6O
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.861
_cell_length_b   11.861
_cell_length_c   12.492
_cell_angle_alpha   61.471
_cell_angle_beta   61.471
_cell_angle_gamma   28.256
_symmetry_Int_Tables_number   1
_cell_volume   724.090
_cell_formula_units_Z   2
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
  Cs  Cs0  1  0.581  0.573  0.553  1.0
  Cs  Cs1  1  0.427  0.419  0.947  1.0
  Cs  Cs2  1  0.419  0.427  0.447  1.0
  Cs  Cs3  1  0.573  0.581  0.053  1.0
  As  As4  1  0.148  0.211  0.215  1.0
  As  As5  1  0.789  0.852  0.285  1.0
  As  As6  1  0.852  0.789  0.785  1.0
  As  As7  1  0.211  0.148  0.715  1.0
  Se  Se8  1  0.737  0.638  0.187  1.0
  Se  Se9  1  0.362  0.263  0.313  1.0
  Se  Se10  1  0.263  0.362  0.813  1.0
  Se  Se11  1  0.638  0.737  0.687  1.0
  Se  Se12  1  0.193  0.195  0.397  1.0
  Se  Se13  1  0.805  0.807  0.103  1.0
  Se  Se14  1  0.807  0.805  0.603  1.0
  Se  Se15  1  0.195  0.193  0.897  1.0
  Se  Se16  1  0.019  0.098  0.319  1.0
  Se  Se17  1  0.902  0.981  0.181  1.0
  Se  Se18  1  0.981  0.902  0.681  1.0
  Se  Se19  1  0.098  0.019  0.819  1.0
  O  O20  1  0.919  0.081  0.750  1.0
  O  O21  1  0.081  0.919  0.250  1.0
[/CIF]
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