The structure described by MgCr3Se3(SO8)3 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(13), one O(2), one O(21), one O(24), one O(3), and one O(7) atom to form MgO6 octahedra that share  a cornercorner with one Se(1)O4 tetrahedra,  a cornercorner with one Se(2)O4 tetrahedra,  a cornercorner with one Se(3)O4 tetrahedra,  a cornercorner with one S(1)O4 tetrahedra,  a cornercorner with one S(2)O4 tetrahedra, and  a cornercorner with one S(3)O4 tetrahedra. There are three inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(12), one O(18), one O(22), one O(23), and one O(4) atom to form CrO6 octahedra that share  a cornercorner with one Se(1)O4 tetrahedra,  a cornercorner with one Se(2)O4 tetrahedra,  a cornercorner with one Se(3)O4 tetrahedra,  a cornercorner with one S(1)O4 tetrahedra,  a cornercorner with one S(2)O4 tetrahedra, and  a cornercorner with one S(3)O4 tetrahedra. In the second Cr site, Cr(2) is bonded to one O(10), one O(14), one O(17), one O(20), one O(6), and one O(9) atom to form CrO6 octahedra that share  a cornercorner with one Se(1)O4 tetrahedra,  a cornercorner with one Se(2)O4 tetrahedra,  a cornercorner with one Se(3)O4 tetrahedra,  a cornercorner with one S(1)O4 tetrahedra,  a cornercorner with one S(2)O4 tetrahedra, and  a cornercorner with one S(3)O4 tetrahedra. In the third Cr site, Cr(3) is bonded to one O(11), one O(15), one O(16), one O(19), one O(5), and one O(8) atom to form CrO6 octahedra that share  a cornercorner with one Se(1)O4 tetrahedra,  a cornercorner with one Se(2)O4 tetrahedra,  a cornercorner with one Se(3)O4 tetrahedra,  a cornercorner with one S(1)O4 tetrahedra,  a cornercorner with one S(2)O4 tetrahedra, and  a cornercorner with one S(3)O4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to one O(1), one O(15), one O(2), and one O(6) atom to form SeO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  a cornercorner with one Cr(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 36-50°. In the second Se site, Se(2) is bonded to one O(12), one O(3), one O(8), and one O(9) atom to form SeO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  a cornercorner with one Cr(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 35-48°. In the third Se site, Se(3) is bonded to one O(13), one O(16), one O(17), and one O(22) atom to form SeO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  a cornercorner with one Cr(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 36-49°. There are three inequivalent S sites. In the first S site, S(1) is bonded to one O(11), one O(20), one O(4), and one O(7) atom to form SO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  a cornercorner with one Cr(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-43°. In the second S site, S(2) is bonded to one O(14), one O(18), one O(21), and one O(5) atom to form SO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  a cornercorner with one Cr(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 27-43°. In the third S site, S(3) is bonded to one O(10), one O(19), one O(23), and one O(24) atom to form SO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  a cornercorner with one Cr(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 26-41°. There are twenty-four inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Cr(1) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Mg(1) and one Se(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Mg(1) and one Se(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Cr(1) and one S(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Cr(3) and one S(2) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Cr(2) and one Se(1) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Mg(1) and one S(1) atom. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to one Cr(3) and one Se(2) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Cr(2) and one Se(2) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Cr(2) and one S(3) atom. In the eleventh O site, O(11) is bonded in a bent 150 degrees geometry to one Cr(3) and one S(1) atom. In the twelfth O site, O(12) is bonded in a bent 120 degrees geometry to one Cr(1) and one Se(2) atom. In the thirteenth O site, O(13) is bonded in a distorted bent 150 degrees geometry to one Mg(1) and one Se(3) atom. In the fourteenth O site, O(14) is bonded in a distorted bent 150 degrees geometry to one Cr(2) and one S(2) atom. In the fifteenth O site, O(15) is bonded in a bent 150 degrees geometry to one Cr(3) and one Se(1) atom. In the sixteenth O site, O(16) is bonded in a bent 150 degrees geometry to one Cr(3) and one Se(3) atom. In the seventeenth O site, O(17) is bonded in a bent 120 degrees geometry to one Cr(2) and one Se(3) atom. In the eighteenth O site, O(18) is bonded in a bent 150 degrees geometry to one Cr(1) and one S(2) atom. In the nineteenth O site, O(19) is bonded in a bent 150 degrees geometry to one Cr(3) and one S(3) atom. In the twentieth O site, O(20) is bonded in a bent 150 degrees geometry to one Cr(2) and one S(1) atom. In the twenty-first O site, O(21) is bonded in a bent 150 degrees geometry to one Mg(1) and one S(2) atom. In the twenty-second O site, O(22) is bonded in a bent 150 degrees geometry to one Cr(1) and one Se(3) atom. In the twenty-third O site, O(23) is bonded in a bent 150 degrees geometry to one Cr(1) and one S(3) atom. In the twenty-fourth O site, O(24) is bonded in a bent 150 degrees geometry to one Mg(1) and one S(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCr3Se3(SO8)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.464
_cell_length_b   8.467
_cell_length_c   8.963
_cell_angle_alpha   90.267
_cell_angle_beta   117.409
_cell_angle_gamma   119.752
_symmetry_Int_Tables_number   1
_cell_volume   471.886
_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
  Mg  Mg0  1  0.710  0.868  0.563  1.0
  Cr  Cr1  1  0.304  0.146  0.451  1.0
  Cr  Cr2  1  0.703  0.347  0.068  1.0
  Cr  Cr3  1  0.293  0.648  0.930  1.0
  Se  Se4  1  0.790  0.745  0.255  1.0
  Se  Se5  1  0.789  0.536  0.750  1.0
  Se  Se6  1  0.206  0.462  0.253  1.0
  S  S7  1  0.493  0.963  0.748  1.0
  S  S8  1  0.499  0.038  0.249  1.0
  S  S9  1  0.223  0.259  0.750  1.0
  O  O10  1  0.988  0.973  0.300  1.0
  O  O11  1  0.731  0.710  0.408  1.0
  O  O12  1  0.710  0.681  0.712  1.0
  O  O13  1  0.319  0.981  0.605  1.0
  O  O14  1  0.372  0.886  0.081  1.0
  O  O15  1  0.868  0.602  0.240  1.0
  O  O16  1  0.650  0.992  0.707  1.0
  O  O17  1  0.020  0.627  0.760  1.0
  O  O18  1  0.830  0.509  0.946  1.0
  O  O19  1  0.416  0.306  0.919  1.0
  O  O20  1  0.380  0.770  0.764  1.0
  O  O21  1  0.619  0.320  0.594  1.0
  O  O22  1  0.368  0.670  0.404  1.0
  O  O23  1  0.592  0.227  0.221  1.0
  O  O24  1  0.587  0.701  0.058  1.0
  O  O25  1  0.178  0.473  0.056  1.0
  O  O26  1  0.964  0.346  0.228  1.0
  O  O27  1  0.341  0.013  0.298  1.0
  O  O28  1  0.169  0.398  0.763  1.0
  O  O29  1  0.601  0.105  0.917  1.0
  O  O30  1  0.669  0.026  0.389  1.0
  O  O31  1  0.295  0.316  0.302  1.0
  O  O32  1  0.280  0.287  0.609  1.0
  O  O33  1  0.043  0.065  0.703  1.0
[/CIF]
.
The structure described by MgCr3Se3(SO8)3 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(13), one O(2), one O(21), one O(24), one O(3), and one O(7) atom to form MgO6 octahedra that share  a cornercorner with one Se(1)O4 tetrahedra,  a cornercorner with one Se(2)O4 tetrahedra,  a cornercorner with one Se(3)O4 tetrahedra,  a cornercorner with one S(1)O4 tetrahedra,  a cornercorner with one S(2)O4 tetrahedra, and  a cornercorner with one S(3)O4 tetrahedra. There are three inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(12), one O(18), one O(22), one O(23), and one O(4) atom to form CrO6 octahedra that share  a cornercorner with one Se(1)O4 tetrahedra,  a cornercorner with one Se(2)O4 tetrahedra,  a cornercorner with one Se(3)O4 tetrahedra,  a cornercorner with one S(1)O4 tetrahedra,  a cornercorner with one S(2)O4 tetrahedra, and  a cornercorner with one S(3)O4 tetrahedra. In the second Cr site, Cr(2) is bonded to one O(10), one O(14), one O(17), one O(20), one O(6), and one O(9) atom to form CrO6 octahedra that share  a cornercorner with one Se(1)O4 tetrahedra,  a cornercorner with one Se(2)O4 tetrahedra,  a cornercorner with one Se(3)O4 tetrahedra,  a cornercorner with one S(1)O4 tetrahedra,  a cornercorner with one S(2)O4 tetrahedra, and  a cornercorner with one S(3)O4 tetrahedra. In the third Cr site, Cr(3) is bonded to one O(11), one O(15), one O(16), one O(19), one O(5), and one O(8) atom to form CrO6 octahedra that share  a cornercorner with one Se(1)O4 tetrahedra,  a cornercorner with one Se(2)O4 tetrahedra,  a cornercorner with one Se(3)O4 tetrahedra,  a cornercorner with one S(1)O4 tetrahedra,  a cornercorner with one S(2)O4 tetrahedra, and  a cornercorner with one S(3)O4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to one O(1), one O(15), one O(2), and one O(6) atom to form SeO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  a cornercorner with one Cr(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 36-50°. In the second Se site, Se(2) is bonded to one O(12), one O(3), one O(8), and one O(9) atom to form SeO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  a cornercorner with one Cr(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 35-48°. In the third Se site, Se(3) is bonded to one O(13), one O(16), one O(17), and one O(22) atom to form SeO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  a cornercorner with one Cr(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 36-49°. There are three inequivalent S sites. In the first S site, S(1) is bonded to one O(11), one O(20), one O(4), and one O(7) atom to form SO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  a cornercorner with one Cr(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-43°. In the second S site, S(2) is bonded to one O(14), one O(18), one O(21), and one O(5) atom to form SO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  a cornercorner with one Cr(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 27-43°. In the third S site, S(3) is bonded to one O(10), one O(19), one O(23), and one O(24) atom to form SO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  a cornercorner with one Cr(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 26-41°. There are twenty-four inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Cr(1) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Mg(1) and one Se(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Mg(1) and one Se(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Cr(1) and one S(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Cr(3) and one S(2) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Cr(2) and one Se(1) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Mg(1) and one S(1) atom. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to one Cr(3) and one Se(2) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Cr(2) and one Se(2) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Cr(2) and one S(3) atom. In the eleventh O site, O(11) is bonded in a bent 150 degrees geometry to one Cr(3) and one S(1) atom. In the twelfth O site, O(12) is bonded in a bent 120 degrees geometry to one Cr(1) and one Se(2) atom. In the thirteenth O site, O(13) is bonded in a distorted bent 150 degrees geometry to one Mg(1) and one Se(3) atom. In the fourteenth O site, O(14) is bonded in a distorted bent 150 degrees geometry to one Cr(2) and one S(2) atom. In the fifteenth O site, O(15) is bonded in a bent 150 degrees geometry to one Cr(3) and one Se(1) atom. In the sixteenth O site, O(16) is bonded in a bent 150 degrees geometry to one Cr(3) and one Se(3) atom. In the seventeenth O site, O(17) is bonded in a bent 120 degrees geometry to one Cr(2) and one Se(3) atom. In the eighteenth O site, O(18) is bonded in a bent 150 degrees geometry to one Cr(1) and one S(2) atom. In the nineteenth O site, O(19) is bonded in a bent 150 degrees geometry to one Cr(3) and one S(3) atom. In the twentieth O site, O(20) is bonded in a bent 150 degrees geometry to one Cr(2) and one S(1) atom. In the twenty-first O site, O(21) is bonded in a bent 150 degrees geometry to one Mg(1) and one S(2) atom. In the twenty-second O site, O(22) is bonded in a bent 150 degrees geometry to one Cr(1) and one Se(3) atom. In the twenty-third O site, O(23) is bonded in a bent 150 degrees geometry to one Cr(1) and one S(3) atom. In the twenty-fourth O site, O(24) is bonded in a bent 150 degrees geometry to one Mg(1) and one S(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCr3Se3(SO8)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.464
_cell_length_b   8.467
_cell_length_c   8.963
_cell_angle_alpha   90.267
_cell_angle_beta   117.409
_cell_angle_gamma   119.752
_symmetry_Int_Tables_number   1
_cell_volume   471.886
_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
  Mg  Mg0  1  0.710  0.868  0.563  1.0
  Cr  Cr1  1  0.304  0.146  0.451  1.0
  Cr  Cr2  1  0.703  0.347  0.068  1.0
  Cr  Cr3  1  0.293  0.648  0.930  1.0
  Se  Se4  1  0.790  0.745  0.255  1.0
  Se  Se5  1  0.789  0.536  0.750  1.0
  Se  Se6  1  0.206  0.462  0.253  1.0
  S  S7  1  0.493  0.963  0.748  1.0
  S  S8  1  0.499  0.038  0.249  1.0
  S  S9  1  0.223  0.259  0.750  1.0
  O  O10  1  0.988  0.973  0.300  1.0
  O  O11  1  0.731  0.710  0.408  1.0
  O  O12  1  0.710  0.681  0.712  1.0
  O  O13  1  0.319  0.981  0.605  1.0
  O  O14  1  0.372  0.886  0.081  1.0
  O  O15  1  0.868  0.602  0.240  1.0
  O  O16  1  0.650  0.992  0.707  1.0
  O  O17  1  0.020  0.627  0.760  1.0
  O  O18  1  0.830  0.509  0.946  1.0
  O  O19  1  0.416  0.306  0.919  1.0
  O  O20  1  0.380  0.770  0.764  1.0
  O  O21  1  0.619  0.320  0.594  1.0
  O  O22  1  0.368  0.670  0.404  1.0
  O  O23  1  0.592  0.227  0.221  1.0
  O  O24  1  0.587  0.701  0.058  1.0
  O  O25  1  0.178  0.473  0.056  1.0
  O  O26  1  0.964  0.346  0.228  1.0
  O  O27  1  0.341  0.013  0.298  1.0
  O  O28  1  0.169  0.398  0.763  1.0
  O  O29  1  0.601  0.105  0.917  1.0
  O  O30  1  0.669  0.026  0.389  1.0
  O  O31  1  0.295  0.316  0.302  1.0
  O  O32  1  0.280  0.287  0.609  1.0
  O  O33  1  0.043  0.065  0.703  1.0
[/CIF]
.