The material described by Ba10MgAs6(O12Cl)2 crystallizes in the monoclinic Pm space group. There are eight inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one O(10), one O(11), one O(13), one O(14), one O(18), one O(3), one O(6), one O(7), and one O(9) atom. In the second Ba site, Ba(2) is bonded in a 7-coordinate geometry to one O(12), one O(15), one O(16), one O(2), one O(4), one O(5), and one O(8) atom. In the third Ba site, Ba(3) is bonded in a 7-coordinate geometry to one O(11), two equivalent O(10), two equivalent O(5), and two equivalent Cl(1) atoms. In the fourth Ba site, Ba(4) is bonded in a 8-coordinate geometry to one O(17), one O(9), two equivalent O(1), two equivalent O(13), and two equivalent Cl(1) atoms. In the fifth Ba site, Ba(5) is bonded in a 6-coordinate geometry to one O(15), one O(18), two equivalent O(16), two equivalent O(3), and two equivalent Cl(1) atoms. In the sixth Ba site, Ba(6) is bonded in a 8-coordinate geometry to one O(12), one O(7), two equivalent O(1), two equivalent O(10), and two equivalent Cl(1) atoms. In the seventh Ba site, Ba(7) is bonded in a 7-coordinate geometry to one O(8), two equivalent O(13), two equivalent O(16), and two equivalent Cl(1) atoms. In the eighth Ba site, Ba(8) is bonded in a 8-coordinate geometry to one O(14), one O(4), two equivalent O(3), two equivalent O(5), and two equivalent Cl(1) atoms. Mg(1) is bonded in a distorted T-shaped geometry to one O(15), one O(17), and one O(2) atom. There are six inequivalent As sites. In the first As site, As(1) is bonded in a distorted trigonal non-coplanar geometry to one O(11) and two equivalent O(13) atoms. In the second As site, As(2) is bonded in a tetrahedral geometry to one O(4), one O(6), and two equivalent O(1) atoms. In the third As site, As(3) is bonded in a tetrahedral geometry to one O(12), one O(14), and two equivalent O(16) atoms. In the fourth As site, As(4) is bonded in a tetrahedral geometry to one O(2), one O(9), and two equivalent O(3) atoms. In the fifth As site, As(5) is bonded in a tetrahedral geometry to one O(7), one O(8), and two equivalent O(5) atoms. In the sixth As site, As(6) is bonded in a tetrahedral geometry to one O(17), one O(18), and two equivalent O(10) atoms. There are eighteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Ba(4), one Ba(6), and one As(2) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to two equivalent Ba(2), one Mg(1), and one As(4) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to one Ba(1), one Ba(5), one Ba(8), and one As(4) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Ba(8), two equivalent Ba(2), and one As(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Ba(2), one Ba(3), one Ba(8), and one As(5) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to two equivalent Ba(1) and one As(2) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Ba(6), two equivalent Ba(1), and one As(5) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Ba(7), two equivalent Ba(2), and one As(5) atom. In the ninth O site, O(9) is bonded in a distorted single-bond geometry to one Ba(4), two equivalent Ba(1), and one As(4) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Ba(1), one Ba(3), one Ba(6), and one As(6) atom. In the eleventh O site, O(11) is bonded to one Ba(3), two equivalent Ba(1), and one As(1) atom to form distorted OBa3As tetrahedra that share corners with two equivalent Cl(1)Ba6 octahedra. The corner-sharing octahedral tilt angles are 47°. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Ba(6), two equivalent Ba(2), and one As(3) atom. In the thirteenth O site, O(13) is bonded in a 4-coordinate geometry to one Ba(1), one Ba(4), one Ba(7), and one As(1) atom. In the fourteenth O site, O(14) is bonded in a distorted single-bond geometry to one Ba(8), two equivalent Ba(1), and one As(3) atom. In the fifteenth O site, O(15) is bonded in a distorted see-saw-like geometry to one Ba(5), two equivalent Ba(2), and one Mg(1) atom. In the sixteenth O site, O(16) is bonded to one Ba(2), one Ba(5), one Ba(7), and one As(3) atom to form distorted OBa3As trigonal pyramids that share corners with two equivalent Cl(1)Ba6 octahedra,  a cornercorner with one O(16)Ba3As trigonal pyramid,  an edgeedge with one Cl(1)Ba6 octahedra, and  an edgeedge with one O(16)Ba3As trigonal pyramid. The corner-sharing octahedral tilt angles range from 60-80°. In the seventeenth O site, O(17) is bonded in a 3-coordinate geometry to one Ba(4), one Mg(1), and one As(6) atom. In the eighteenth O site, O(18) is bonded in a 4-coordinate geometry to one Ba(5), two equivalent Ba(1), and one As(6) atom. Cl(1) is bonded to one Ba(3), one Ba(4), one Ba(5), one Ba(6), one Ba(7), and one Ba(8) atom to form distorted ClBa6 octahedra that share  a cornercorner with one O(11)Ba3As tetrahedra, corners with two equivalent O(16)Ba3As trigonal pyramids,  an edgeedge with one O(16)Ba3As trigonal pyramid, and faces with two equivalent Cl(1)Ba6 octahedra. is represented by the CIF file [CIF]
data_Ba10MgAs6(ClO12)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.162
_cell_length_b   10.746
_cell_length_c   7.786
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   116.765
_symmetry_Int_Tables_number   1
_cell_volume   833.817
_cell_formula_units_Z   1
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  0.663  0.335  0.502  1.0
  Ba  Ba1  1  0.263  0.639  0.520  1.0
  Ba  Ba2  1  0.990  0.246  0.250  1.0
  Ba  Ba3  1  0.263  0.639  0.980  1.0
  Ba  Ba4  1  0.794  0.752  0.250  1.0
  Ba  Ba5  1  0.278  0.987  0.250  1.0
  Ba  Ba6  1  0.712  0.985  0.750  1.0
  Ba  Ba7  1  0.981  0.753  0.750  1.0
  Ba  Ba8  1  0.663  0.335  0.998  1.0
  Ba  Ba9  1  0.254  0.252  0.750  1.0
  Mg  Mg10  1  0.488  0.720  0.250  1.0
  As  As11  1  0.970  0.570  0.250  1.0
  As  As12  1  0.562  0.617  0.750  1.0
  As  As13  1  0.348  0.954  0.750  1.0
  As  As14  1  0.418  0.386  0.250  1.0
  As  As15  1  0.002  0.383  0.750  1.0
  As  As16  1  0.663  0.057  0.250  1.0
  Cl  Cl17  1  0.992  0.001  0.997  1.0
  Cl  Cl18  1  0.992  0.001  0.503  1.0
  O  O19  1  0.612  0.722  0.932  1.0
  O  O20  1  0.363  0.516  0.250  1.0
  O  O21  1  0.364  0.281  0.428  1.0
  O  O22  1  0.387  0.529  0.750  1.0
  O  O23  1  0.076  0.350  0.572  1.0
  O  O24  1  0.632  0.502  0.750  1.0
  O  O25  1  0.830  0.302  0.750  1.0
  O  O26  1  0.061  0.563  0.750  1.0
  O  O27  1  0.592  0.473  0.250  1.0
  O  O28  1  0.751  0.125  0.064  1.0
  O  O29  1  0.076  0.350  0.928  1.0
  O  O30  1  0.847  0.393  0.250  1.0
  O  O31  1  0.437  0.857  0.750  1.0
  O  O32  1  0.915  0.636  0.070  1.0
  O  O33  1  0.915  0.636  0.430  1.0
  O  O34  1  0.452  0.130  0.750  1.0
  O  O35  1  0.364  0.281  0.072  1.0
  O  O36  1  0.751  0.125  0.436  1.0
  O  O37  1  0.346  0.774  0.250  1.0
  O  O38  1  0.239  0.896  0.923  1.0
  O  O39  1  0.645  0.889  0.250  1.0
  O  O40  1  0.239  0.896  0.577  1.0
  O  O41  1  0.612  0.722  0.568  1.0
  O  O42  1  0.538  0.110  0.250  1.0
[/CIF]
.
The material described by Ba10MgAs6(O12Cl)2 crystallizes in the monoclinic Pm space group. There are eight inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one O(10), one O(11), one O(13), one O(14), one O(18), one O(3), one O(6), one O(7), and one O(9) atom. In the second Ba site, Ba(2) is bonded in a 7-coordinate geometry to one O(12), one O(15), one O(16), one O(2), one O(4), one O(5), and one O(8) atom. In the third Ba site, Ba(3) is bonded in a 7-coordinate geometry to one O(11), two equivalent O(10), two equivalent O(5), and two equivalent Cl(1) atoms. In the fourth Ba site, Ba(4) is bonded in a 8-coordinate geometry to one O(17), one O(9), two equivalent O(1), two equivalent O(13), and two equivalent Cl(1) atoms. In the fifth Ba site, Ba(5) is bonded in a 6-coordinate geometry to one O(15), one O(18), two equivalent O(16), two equivalent O(3), and two equivalent Cl(1) atoms. In the sixth Ba site, Ba(6) is bonded in a 8-coordinate geometry to one O(12), one O(7), two equivalent O(1), two equivalent O(10), and two equivalent Cl(1) atoms. In the seventh Ba site, Ba(7) is bonded in a 7-coordinate geometry to one O(8), two equivalent O(13), two equivalent O(16), and two equivalent Cl(1) atoms. In the eighth Ba site, Ba(8) is bonded in a 8-coordinate geometry to one O(14), one O(4), two equivalent O(3), two equivalent O(5), and two equivalent Cl(1) atoms. Mg(1) is bonded in a distorted T-shaped geometry to one O(15), one O(17), and one O(2) atom. There are six inequivalent As sites. In the first As site, As(1) is bonded in a distorted trigonal non-coplanar geometry to one O(11) and two equivalent O(13) atoms. In the second As site, As(2) is bonded in a tetrahedral geometry to one O(4), one O(6), and two equivalent O(1) atoms. In the third As site, As(3) is bonded in a tetrahedral geometry to one O(12), one O(14), and two equivalent O(16) atoms. In the fourth As site, As(4) is bonded in a tetrahedral geometry to one O(2), one O(9), and two equivalent O(3) atoms. In the fifth As site, As(5) is bonded in a tetrahedral geometry to one O(7), one O(8), and two equivalent O(5) atoms. In the sixth As site, As(6) is bonded in a tetrahedral geometry to one O(17), one O(18), and two equivalent O(10) atoms. There are eighteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Ba(4), one Ba(6), and one As(2) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to two equivalent Ba(2), one Mg(1), and one As(4) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to one Ba(1), one Ba(5), one Ba(8), and one As(4) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Ba(8), two equivalent Ba(2), and one As(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Ba(2), one Ba(3), one Ba(8), and one As(5) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to two equivalent Ba(1) and one As(2) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Ba(6), two equivalent Ba(1), and one As(5) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Ba(7), two equivalent Ba(2), and one As(5) atom. In the ninth O site, O(9) is bonded in a distorted single-bond geometry to one Ba(4), two equivalent Ba(1), and one As(4) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Ba(1), one Ba(3), one Ba(6), and one As(6) atom. In the eleventh O site, O(11) is bonded to one Ba(3), two equivalent Ba(1), and one As(1) atom to form distorted OBa3As tetrahedra that share corners with two equivalent Cl(1)Ba6 octahedra. The corner-sharing octahedral tilt angles are 47°. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Ba(6), two equivalent Ba(2), and one As(3) atom. In the thirteenth O site, O(13) is bonded in a 4-coordinate geometry to one Ba(1), one Ba(4), one Ba(7), and one As(1) atom. In the fourteenth O site, O(14) is bonded in a distorted single-bond geometry to one Ba(8), two equivalent Ba(1), and one As(3) atom. In the fifteenth O site, O(15) is bonded in a distorted see-saw-like geometry to one Ba(5), two equivalent Ba(2), and one Mg(1) atom. In the sixteenth O site, O(16) is bonded to one Ba(2), one Ba(5), one Ba(7), and one As(3) atom to form distorted OBa3As trigonal pyramids that share corners with two equivalent Cl(1)Ba6 octahedra,  a cornercorner with one O(16)Ba3As trigonal pyramid,  an edgeedge with one Cl(1)Ba6 octahedra, and  an edgeedge with one O(16)Ba3As trigonal pyramid. The corner-sharing octahedral tilt angles range from 60-80°. In the seventeenth O site, O(17) is bonded in a 3-coordinate geometry to one Ba(4), one Mg(1), and one As(6) atom. In the eighteenth O site, O(18) is bonded in a 4-coordinate geometry to one Ba(5), two equivalent Ba(1), and one As(6) atom. Cl(1) is bonded to one Ba(3), one Ba(4), one Ba(5), one Ba(6), one Ba(7), and one Ba(8) atom to form distorted ClBa6 octahedra that share  a cornercorner with one O(11)Ba3As tetrahedra, corners with two equivalent O(16)Ba3As trigonal pyramids,  an edgeedge with one O(16)Ba3As trigonal pyramid, and faces with two equivalent Cl(1)Ba6 octahedra. is represented by the CIF file [CIF]
data_Ba10MgAs6(ClO12)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.162
_cell_length_b   10.746
_cell_length_c   7.786
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   116.765
_symmetry_Int_Tables_number   1
_cell_volume   833.817
_cell_formula_units_Z   1
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  0.663  0.335  0.502  1.0
  Ba  Ba1  1  0.263  0.639  0.520  1.0
  Ba  Ba2  1  0.990  0.246  0.250  1.0
  Ba  Ba3  1  0.263  0.639  0.980  1.0
  Ba  Ba4  1  0.794  0.752  0.250  1.0
  Ba  Ba5  1  0.278  0.987  0.250  1.0
  Ba  Ba6  1  0.712  0.985  0.750  1.0
  Ba  Ba7  1  0.981  0.753  0.750  1.0
  Ba  Ba8  1  0.663  0.335  0.998  1.0
  Ba  Ba9  1  0.254  0.252  0.750  1.0
  Mg  Mg10  1  0.488  0.720  0.250  1.0
  As  As11  1  0.970  0.570  0.250  1.0
  As  As12  1  0.562  0.617  0.750  1.0
  As  As13  1  0.348  0.954  0.750  1.0
  As  As14  1  0.418  0.386  0.250  1.0
  As  As15  1  0.002  0.383  0.750  1.0
  As  As16  1  0.663  0.057  0.250  1.0
  Cl  Cl17  1  0.992  0.001  0.997  1.0
  Cl  Cl18  1  0.992  0.001  0.503  1.0
  O  O19  1  0.612  0.722  0.932  1.0
  O  O20  1  0.363  0.516  0.250  1.0
  O  O21  1  0.364  0.281  0.428  1.0
  O  O22  1  0.387  0.529  0.750  1.0
  O  O23  1  0.076  0.350  0.572  1.0
  O  O24  1  0.632  0.502  0.750  1.0
  O  O25  1  0.830  0.302  0.750  1.0
  O  O26  1  0.061  0.563  0.750  1.0
  O  O27  1  0.592  0.473  0.250  1.0
  O  O28  1  0.751  0.125  0.064  1.0
  O  O29  1  0.076  0.350  0.928  1.0
  O  O30  1  0.847  0.393  0.250  1.0
  O  O31  1  0.437  0.857  0.750  1.0
  O  O32  1  0.915  0.636  0.070  1.0
  O  O33  1  0.915  0.636  0.430  1.0
  O  O34  1  0.452  0.130  0.750  1.0
  O  O35  1  0.364  0.281  0.072  1.0
  O  O36  1  0.751  0.125  0.436  1.0
  O  O37  1  0.346  0.774  0.250  1.0
  O  O38  1  0.239  0.896  0.923  1.0
  O  O39  1  0.645  0.889  0.250  1.0
  O  O40  1  0.239  0.896  0.577  1.0
  O  O41  1  0.612  0.722  0.568  1.0
  O  O42  1  0.538  0.110  0.250  1.0
[/CIF]
.