The structure described by BaAs2O5 crystallizes in the triclinic P-1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to one O(4), one O(5), one O(6), one O(7), one O(8), one O(9), two equivalent O(1), and two equivalent O(3) atoms. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to one O(10), one O(2), one O(4), one O(6), one O(7), one O(8), one O(9), and two equivalent O(5) atoms. There are four inequivalent As sites. In the first As site, As(1) is bonded in a distorted T-shaped geometry to one O(1), one O(4), and one O(5) atom. In the second As site, As(2) is bonded in a distorted T-shaped geometry to one O(1), one O(2), and one O(6) atom. In the third As site, As(3) is bonded in a distorted T-shaped geometry to one O(2), one O(3), and one O(7) atom. In the fourth As site, As(4) is bonded in a distorted T-shaped geometry to one O(3), one O(4), and one O(8) atom. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to two equivalent Ba(1), one As(1), and one As(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ba(2), one As(2), and one As(3) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to two equivalent Ba(1), one As(3), and one As(4) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), one As(1), and one As(4) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Ba(1), two equivalent Ba(2), and one As(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Ba(1), one Ba(2), and one As(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Ba(1), one Ba(2), and one As(3) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Ba(1), one Ba(2), and one As(4) atom. In the ninth O site, O(9) is bonded in an L-shaped geometry to one Ba(1) and one Ba(2) atom. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to one Ba(2) and one O(10) atom. is represented by the CIF file [CIF]
data_BaAs2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.343
_cell_length_b   8.921
_cell_length_c   8.667
_cell_angle_alpha   92.207
_cell_angle_beta   89.257
_cell_angle_gamma   76.314
_symmetry_Int_Tables_number   1
_cell_volume   626.187
_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  0.261  0.960  0.860  1.0
  Ba  Ba1  1  0.739  0.040  0.140  1.0
  Ba  Ba2  1  0.236  0.108  0.416  1.0
  Ba  Ba3  1  0.764  0.892  0.584  1.0
  As  As4  1  0.497  0.261  0.758  1.0
  As  As5  1  0.503  0.739  0.242  1.0
  As  As6  1  0.368  0.359  0.119  1.0
  As  As7  1  0.632  0.641  0.881  1.0
  As  As8  1  0.956  0.354  0.130  1.0
  As  As9  1  0.044  0.646  0.870  1.0
  As  As10  1  0.882  0.265  0.761  1.0
  As  As11  1  0.118  0.735  0.239  1.0
  O  O12  1  0.446  0.212  0.958  1.0
  O  O13  1  0.554  0.788  0.042  1.0
  O  O14  1  0.181  0.285  0.150  1.0
  O  O15  1  0.819  0.715  0.850  1.0
  O  O16  1  0.949  0.217  0.963  1.0
  O  O17  1  0.051  0.783  0.037  1.0
  O  O18  1  0.718  0.154  0.779  1.0
  O  O19  1  0.282  0.846  0.221  1.0
  O  O20  1  0.435  0.110  0.663  1.0
  O  O21  1  0.565  0.890  0.337  1.0
  O  O22  1  0.471  0.252  0.264  1.0
  O  O23  1  0.529  0.748  0.736  1.0
  O  O24  1  0.916  0.234  0.270  1.0
  O  O25  1  0.084  0.766  0.730  1.0
  O  O26  1  0.031  0.122  0.666  1.0
  O  O27  1  0.969  0.878  0.334  1.0
  O  O28  1  0.301  0.784  0.553  1.0
  O  O29  1  0.699  0.216  0.447  1.0
  O  O30  1  0.076  0.478  0.503  1.0
  O  O31  1  0.924  0.522  0.497  1.0
[/CIF]
.
The structure described by BaAs2O5 crystallizes in the triclinic P-1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to one O(4), one O(5), one O(6), one O(7), one O(8), one O(9), two equivalent O(1), and two equivalent O(3) atoms. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to one O(10), one O(2), one O(4), one O(6), one O(7), one O(8), one O(9), and two equivalent O(5) atoms. There are four inequivalent As sites. In the first As site, As(1) is bonded in a distorted T-shaped geometry to one O(1), one O(4), and one O(5) atom. In the second As site, As(2) is bonded in a distorted T-shaped geometry to one O(1), one O(2), and one O(6) atom. In the third As site, As(3) is bonded in a distorted T-shaped geometry to one O(2), one O(3), and one O(7) atom. In the fourth As site, As(4) is bonded in a distorted T-shaped geometry to one O(3), one O(4), and one O(8) atom. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to two equivalent Ba(1), one As(1), and one As(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ba(2), one As(2), and one As(3) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to two equivalent Ba(1), one As(3), and one As(4) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), one As(1), and one As(4) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Ba(1), two equivalent Ba(2), and one As(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Ba(1), one Ba(2), and one As(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Ba(1), one Ba(2), and one As(3) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Ba(1), one Ba(2), and one As(4) atom. In the ninth O site, O(9) is bonded in an L-shaped geometry to one Ba(1) and one Ba(2) atom. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to one Ba(2) and one O(10) atom. is represented by the CIF file [CIF]
data_BaAs2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.343
_cell_length_b   8.921
_cell_length_c   8.667
_cell_angle_alpha   92.207
_cell_angle_beta   89.257
_cell_angle_gamma   76.314
_symmetry_Int_Tables_number   1
_cell_volume   626.187
_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  0.261  0.960  0.860  1.0
  Ba  Ba1  1  0.739  0.040  0.140  1.0
  Ba  Ba2  1  0.236  0.108  0.416  1.0
  Ba  Ba3  1  0.764  0.892  0.584  1.0
  As  As4  1  0.497  0.261  0.758  1.0
  As  As5  1  0.503  0.739  0.242  1.0
  As  As6  1  0.368  0.359  0.119  1.0
  As  As7  1  0.632  0.641  0.881  1.0
  As  As8  1  0.956  0.354  0.130  1.0
  As  As9  1  0.044  0.646  0.870  1.0
  As  As10  1  0.882  0.265  0.761  1.0
  As  As11  1  0.118  0.735  0.239  1.0
  O  O12  1  0.446  0.212  0.958  1.0
  O  O13  1  0.554  0.788  0.042  1.0
  O  O14  1  0.181  0.285  0.150  1.0
  O  O15  1  0.819  0.715  0.850  1.0
  O  O16  1  0.949  0.217  0.963  1.0
  O  O17  1  0.051  0.783  0.037  1.0
  O  O18  1  0.718  0.154  0.779  1.0
  O  O19  1  0.282  0.846  0.221  1.0
  O  O20  1  0.435  0.110  0.663  1.0
  O  O21  1  0.565  0.890  0.337  1.0
  O  O22  1  0.471  0.252  0.264  1.0
  O  O23  1  0.529  0.748  0.736  1.0
  O  O24  1  0.916  0.234  0.270  1.0
  O  O25  1  0.084  0.766  0.730  1.0
  O  O26  1  0.031  0.122  0.666  1.0
  O  O27  1  0.969  0.878  0.334  1.0
  O  O28  1  0.301  0.784  0.553  1.0
  O  O29  1  0.699  0.216  0.447  1.0
  O  O30  1  0.076  0.478  0.503  1.0
  O  O31  1  0.924  0.522  0.497  1.0
[/CIF]
.