The compound described by Ba(AsO3)2 crystallizes in the monoclinic C2/c space group. Ba(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), and four equivalent O(3) atoms. There are two inequivalent As sites. In the first As site, As(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form AsO6 octahedra that share edges with two equivalent As(1)O6 octahedra and  an edgeedge with one As(2)O4 tetrahedra. In the second As site, As(2) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form edge-sharing AsO4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Ba(1) and two equivalent As(1) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ba(1), one As(1), and one As(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one As(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba(AsO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.000
_cell_length_b   5.788
_cell_length_c   9.660
_cell_angle_alpha   106.383
_cell_angle_beta   103.785
_cell_angle_gamma   93.945
_symmetry_Int_Tables_number   1
_cell_volume   257.689
_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
  Ba  Ba0  1  0.393  0.143  0.286  1.0
  Ba  Ba1  1  0.607  0.857  0.714  1.0
  As  As2  1  0.785  0.535  0.069  1.0
  As  As3  1  0.215  0.465  0.931  1.0
  As  As4  1  0.939  0.688  0.377  1.0
  As  As5  1  0.061  0.312  0.623  1.0
  O  O6  1  0.101  0.708  0.061  1.0
  O  O7  1  0.460  0.353  0.061  1.0
  O  O8  1  0.899  0.292  0.939  1.0
  O  O9  1  0.540  0.647  0.939  1.0
  O  O10  1  0.761  0.798  0.231  1.0
  O  O11  1  0.971  0.433  0.231  1.0
  O  O12  1  0.239  0.202  0.769  1.0
  O  O13  1  0.029  0.567  0.769  1.0
  O  O14  1  0.231  0.879  0.466  1.0
  O  O15  1  0.734  0.586  0.466  1.0
  O  O16  1  0.769  0.121  0.534  1.0
  O  O17  1  0.266  0.414  0.534  1.0
[/CIF]
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The compound described by Ba(AsO3)2 crystallizes in the monoclinic C2/c space group. Ba(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), and four equivalent O(3) atoms. There are two inequivalent As sites. In the first As site, As(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form AsO6 octahedra that share edges with two equivalent As(1)O6 octahedra and  an edgeedge with one As(2)O4 tetrahedra. In the second As site, As(2) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form edge-sharing AsO4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Ba(1) and two equivalent As(1) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ba(1), one As(1), and one As(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one As(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba(AsO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.000
_cell_length_b   5.788
_cell_length_c   9.660
_cell_angle_alpha   106.383
_cell_angle_beta   103.785
_cell_angle_gamma   93.945
_symmetry_Int_Tables_number   1
_cell_volume   257.689
_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
  Ba  Ba0  1  0.393  0.143  0.286  1.0
  Ba  Ba1  1  0.607  0.857  0.714  1.0
  As  As2  1  0.785  0.535  0.069  1.0
  As  As3  1  0.215  0.465  0.931  1.0
  As  As4  1  0.939  0.688  0.377  1.0
  As  As5  1  0.061  0.312  0.623  1.0
  O  O6  1  0.101  0.708  0.061  1.0
  O  O7  1  0.460  0.353  0.061  1.0
  O  O8  1  0.899  0.292  0.939  1.0
  O  O9  1  0.540  0.647  0.939  1.0
  O  O10  1  0.761  0.798  0.231  1.0
  O  O11  1  0.971  0.433  0.231  1.0
  O  O12  1  0.239  0.202  0.769  1.0
  O  O13  1  0.029  0.567  0.769  1.0
  O  O14  1  0.231  0.879  0.466  1.0
  O  O15  1  0.734  0.586  0.466  1.0
  O  O16  1  0.769  0.121  0.534  1.0
  O  O17  1  0.266  0.414  0.534  1.0
[/CIF]
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