The compound described by BaSe2O5 crystallizes in the monoclinic P2_1/c space group. Ba(1) is bonded in a 9-coordinate geometry to two equivalent O(2), two equivalent O(4), two equivalent O(5), and three equivalent O(1) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted trigonal non-coplanar geometry to one O(1), one O(2), and one O(3) atom. In the second Se site, Se(2) is bonded in a trigonal non-coplanar geometry to one O(3), one O(4), and one O(5) atom. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to three equivalent Ba(1) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one Se(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Se(1) and one Se(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Ba(1) and one Se(2) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one Se(2) atom. is represented by the CIF file [CIF]
data_BaSe2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.759
_cell_length_b   4.580
_cell_length_c   9.801
_cell_angle_alpha   87.645
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   527.385
_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
  Ba  Ba0  1  0.670  0.244  0.037  1.0
  Ba  Ba1  1  0.170  0.756  0.463  1.0
  Ba  Ba2  1  0.330  0.756  0.963  1.0
  Ba  Ba3  1  0.830  0.244  0.537  1.0
  Se  Se4  1  0.606  0.813  0.742  1.0
  Se  Se5  1  0.106  0.187  0.758  1.0
  Se  Se6  1  0.394  0.187  0.258  1.0
  Se  Se7  1  0.894  0.813  0.242  1.0
  Se  Se8  1  0.580  0.732  0.355  1.0
  Se  Se9  1  0.080  0.268  0.145  1.0
  Se  Se10  1  0.420  0.268  0.645  1.0
  Se  Se11  1  0.920  0.732  0.855  1.0
  O  O12  1  0.559  0.757  0.903  1.0
  O  O13  1  0.059  0.243  0.597  1.0
  O  O14  1  0.441  0.243  0.097  1.0
  O  O15  1  0.941  0.757  0.403  1.0
  O  O16  1  0.656  0.155  0.741  1.0
  O  O17  1  0.156  0.845  0.759  1.0
  O  O18  1  0.344  0.845  0.259  1.0
  O  O19  1  0.844  0.155  0.241  1.0
  O  O20  1  0.536  0.118  0.343  1.0
  O  O21  1  0.036  0.882  0.157  1.0
  O  O22  1  0.464  0.882  0.657  1.0
  O  O23  1  0.964  0.118  0.843  1.0
  O  O24  1  0.860  0.713  0.701  1.0
  O  O25  1  0.360  0.287  0.799  1.0
  O  O26  1  0.140  0.287  0.299  1.0
  O  O27  1  0.640  0.713  0.201  1.0
  O  O28  1  0.810  0.766  0.961  1.0
  O  O29  1  0.310  0.234  0.539  1.0
  O  O30  1  0.190  0.234  0.039  1.0
  O  O31  1  0.690  0.766  0.461  1.0
[/CIF]
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The compound described by BaSe2O5 crystallizes in the monoclinic P2_1/c space group. Ba(1) is bonded in a 9-coordinate geometry to two equivalent O(2), two equivalent O(4), two equivalent O(5), and three equivalent O(1) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted trigonal non-coplanar geometry to one O(1), one O(2), and one O(3) atom. In the second Se site, Se(2) is bonded in a trigonal non-coplanar geometry to one O(3), one O(4), and one O(5) atom. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to three equivalent Ba(1) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one Se(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Se(1) and one Se(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Ba(1) and one Se(2) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one Se(2) atom. is represented by the CIF file [CIF]
data_BaSe2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.759
_cell_length_b   4.580
_cell_length_c   9.801
_cell_angle_alpha   87.645
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   527.385
_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
  Ba  Ba0  1  0.670  0.244  0.037  1.0
  Ba  Ba1  1  0.170  0.756  0.463  1.0
  Ba  Ba2  1  0.330  0.756  0.963  1.0
  Ba  Ba3  1  0.830  0.244  0.537  1.0
  Se  Se4  1  0.606  0.813  0.742  1.0
  Se  Se5  1  0.106  0.187  0.758  1.0
  Se  Se6  1  0.394  0.187  0.258  1.0
  Se  Se7  1  0.894  0.813  0.242  1.0
  Se  Se8  1  0.580  0.732  0.355  1.0
  Se  Se9  1  0.080  0.268  0.145  1.0
  Se  Se10  1  0.420  0.268  0.645  1.0
  Se  Se11  1  0.920  0.732  0.855  1.0
  O  O12  1  0.559  0.757  0.903  1.0
  O  O13  1  0.059  0.243  0.597  1.0
  O  O14  1  0.441  0.243  0.097  1.0
  O  O15  1  0.941  0.757  0.403  1.0
  O  O16  1  0.656  0.155  0.741  1.0
  O  O17  1  0.156  0.845  0.759  1.0
  O  O18  1  0.344  0.845  0.259  1.0
  O  O19  1  0.844  0.155  0.241  1.0
  O  O20  1  0.536  0.118  0.343  1.0
  O  O21  1  0.036  0.882  0.157  1.0
  O  O22  1  0.464  0.882  0.657  1.0
  O  O23  1  0.964  0.118  0.843  1.0
  O  O24  1  0.860  0.713  0.701  1.0
  O  O25  1  0.360  0.287  0.799  1.0
  O  O26  1  0.140  0.287  0.299  1.0
  O  O27  1  0.640  0.713  0.201  1.0
  O  O28  1  0.810  0.766  0.961  1.0
  O  O29  1  0.310  0.234  0.539  1.0
  O  O30  1  0.190  0.234  0.039  1.0
  O  O31  1  0.690  0.766  0.461  1.0
[/CIF]
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