The structure described by K2MgH8(SO6)2 crystallizes in the monoclinic C2 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 4-coordinate geometry to one O(1), one O(11), one O(13), and one O(4) atom. In the second K site, K(2) is bonded in a 4-coordinate geometry to one O(12), one O(13), one O(2), and one O(4) atom. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(5), one O(6), two equivalent O(3), and two equivalent O(7) atoms to form MgO6 octahedra that share corners with two equivalent S(2)O4 tetrahedra. In the second Mg site, Mg(2) is bonded in a 6-coordinate geometry to two equivalent O(4), two equivalent O(8), and two equivalent O(9) atoms. There are eight inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(5) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(6) atom. In the third H site, H(3) is bonded in a single-bond geometry to one O(1) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(2) atom. In the fifth H site, H(5) is bonded in a distorted single-bond geometry to one O(11) and one O(7) atom. In the sixth H site, H(6) is bonded in a single-bond geometry to one O(7) atom. In the seventh H site, H(7) is bonded in a single-bond geometry to one O(1) atom. In the eighth H site, H(8) is bonded in a single-bond geometry to one O(2) atom. There are two inequivalent S sites. In the first S site, S(1) is bonded in a tetrahedral geometry to one O(10), one O(11), one O(12), and one O(13) atom. In the second S site, S(2) is bonded to one O(3), one O(4), one O(8), and one O(9) atom to form SO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 6°. There are thirteen inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to one K(1), one H(3), and one H(7) atom. In the second O site, O(2) is bonded in a water-like geometry to one K(2), one H(4), and one H(8) atom. In the third O site, O(3) is bonded in a linear geometry to one Mg(1) and one S(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one K(1), one K(2), one Mg(2), and one S(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Mg(1) and two equivalent H(1) atoms. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Mg(1) and two equivalent H(2) atoms. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one H(5), and one H(6) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to one Mg(2) and one S(2) atom. In the ninth O site, O(9) is bonded in a distorted L-shaped geometry to one Mg(2) and one S(2) atom. In the tenth O site, O(10) is bonded in a single-bond geometry to one S(1) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one K(1), one H(5), and one S(1) atom. In the twelfth O site, O(12) is bonded in a distorted single-bond geometry to one K(2) and one S(1) atom. In the thirteenth O site, O(13) is bonded in a distorted single-bond geometry to one K(1), one K(2), and one S(1) atom. is represented by the CIF file [CIF]
data_K2MgH8(SO6)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.067
_cell_length_b   8.067
_cell_length_c   9.805
_cell_angle_alpha   94.715
_cell_angle_beta   94.715
_cell_angle_gamma   85.471
_symmetry_Int_Tables_number   1
_cell_volume   632.015
_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
  K  K0  1  0.099  0.540  0.296  1.0
  K  K1  1  0.533  0.117  0.294  1.0
  K  K2  1  0.883  0.467  0.706  1.0
  K  K3  1  0.460  0.901  0.704  1.0
  Mg  Mg4  1  0.004  0.996  0.000  1.0
  Mg  Mg5  1  0.504  0.496  0.000  1.0
  H  H6  1  0.191  0.694  0.951  1.0
  H  H7  1  0.717  0.193  0.934  1.0
  H  H8  1  0.807  0.283  0.066  1.0
  H  H9  1  0.306  0.809  0.049  1.0
  H  H10  1  0.142  0.688  0.632  1.0
  H  H11  1  0.697  0.142  0.631  1.0
  H  H12  1  0.858  0.303  0.369  1.0
  H  H13  1  0.312  0.858  0.368  1.0
  H  H14  1  0.940  0.931  0.256  1.0
  H  H15  1  0.069  0.060  0.744  1.0
  H  H16  1  0.953  0.912  0.719  1.0
  H  H17  1  0.088  0.047  0.281  1.0
  H  H18  1  0.284  0.542  0.631  1.0
  H  H19  1  0.543  0.273  0.630  1.0
  H  H20  1  0.727  0.457  0.370  1.0
  H  H21  1  0.458  0.716  0.369  1.0
  S  S22  1  0.787  0.790  0.476  1.0
  S  S23  1  0.210  0.213  0.524  1.0
  S  S24  1  0.296  0.302  0.008  1.0
  S  S25  1  0.698  0.704  0.992  1.0
  O  O26  1  0.249  0.649  0.679  1.0
  O  O27  1  0.649  0.240  0.684  1.0
  O  O28  1  0.760  0.351  0.316  1.0
  O  O29  1  0.351  0.751  0.321  1.0
  O  O30  1  0.825  0.820  0.987  1.0
  O  O31  1  0.180  0.175  0.013  1.0
  O  O32  1  0.353  0.378  0.149  1.0
  O  O33  1  0.622  0.647  0.851  1.0
  O  O34  1  0.195  0.805  0.000  1.0
  O  O35  1  0.814  0.186  0.000  1.0
  O  O36  1  0.988  0.000  0.790  1.0
  O  O37  1  1.000  0.012  0.210  1.0
  O  O38  1  0.230  0.448  0.928  1.0
  O  O39  1  0.457  0.238  0.947  1.0
  O  O40  1  0.762  0.543  0.053  1.0
  O  O41  1  0.552  0.770  0.072  1.0
  O  O42  1  0.347  0.329  0.528  1.0
  O  O43  1  0.671  0.653  0.472  1.0
  O  O44  1  0.861  0.788  0.342  1.0
  O  O45  1  0.212  0.139  0.658  1.0
  O  O46  1  0.923  0.760  0.589  1.0
  O  O47  1  0.693  0.952  0.509  1.0
  O  O48  1  0.048  0.307  0.491  1.0
  O  O49  1  0.240  0.077  0.411  1.0
[/CIF]
.
The structure described by K2MgH8(SO6)2 crystallizes in the monoclinic C2 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 4-coordinate geometry to one O(1), one O(11), one O(13), and one O(4) atom. In the second K site, K(2) is bonded in a 4-coordinate geometry to one O(12), one O(13), one O(2), and one O(4) atom. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(5), one O(6), two equivalent O(3), and two equivalent O(7) atoms to form MgO6 octahedra that share corners with two equivalent S(2)O4 tetrahedra. In the second Mg site, Mg(2) is bonded in a 6-coordinate geometry to two equivalent O(4), two equivalent O(8), and two equivalent O(9) atoms. There are eight inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(5) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(6) atom. In the third H site, H(3) is bonded in a single-bond geometry to one O(1) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(2) atom. In the fifth H site, H(5) is bonded in a distorted single-bond geometry to one O(11) and one O(7) atom. In the sixth H site, H(6) is bonded in a single-bond geometry to one O(7) atom. In the seventh H site, H(7) is bonded in a single-bond geometry to one O(1) atom. In the eighth H site, H(8) is bonded in a single-bond geometry to one O(2) atom. There are two inequivalent S sites. In the first S site, S(1) is bonded in a tetrahedral geometry to one O(10), one O(11), one O(12), and one O(13) atom. In the second S site, S(2) is bonded to one O(3), one O(4), one O(8), and one O(9) atom to form SO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 6°. There are thirteen inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to one K(1), one H(3), and one H(7) atom. In the second O site, O(2) is bonded in a water-like geometry to one K(2), one H(4), and one H(8) atom. In the third O site, O(3) is bonded in a linear geometry to one Mg(1) and one S(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one K(1), one K(2), one Mg(2), and one S(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Mg(1) and two equivalent H(1) atoms. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Mg(1) and two equivalent H(2) atoms. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one H(5), and one H(6) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to one Mg(2) and one S(2) atom. In the ninth O site, O(9) is bonded in a distorted L-shaped geometry to one Mg(2) and one S(2) atom. In the tenth O site, O(10) is bonded in a single-bond geometry to one S(1) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one K(1), one H(5), and one S(1) atom. In the twelfth O site, O(12) is bonded in a distorted single-bond geometry to one K(2) and one S(1) atom. In the thirteenth O site, O(13) is bonded in a distorted single-bond geometry to one K(1), one K(2), and one S(1) atom. is represented by the CIF file [CIF]
data_K2MgH8(SO6)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.067
_cell_length_b   8.067
_cell_length_c   9.805
_cell_angle_alpha   94.715
_cell_angle_beta   94.715
_cell_angle_gamma   85.471
_symmetry_Int_Tables_number   1
_cell_volume   632.015
_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
  K  K0  1  0.099  0.540  0.296  1.0
  K  K1  1  0.533  0.117  0.294  1.0
  K  K2  1  0.883  0.467  0.706  1.0
  K  K3  1  0.460  0.901  0.704  1.0
  Mg  Mg4  1  0.004  0.996  0.000  1.0
  Mg  Mg5  1  0.504  0.496  0.000  1.0
  H  H6  1  0.191  0.694  0.951  1.0
  H  H7  1  0.717  0.193  0.934  1.0
  H  H8  1  0.807  0.283  0.066  1.0
  H  H9  1  0.306  0.809  0.049  1.0
  H  H10  1  0.142  0.688  0.632  1.0
  H  H11  1  0.697  0.142  0.631  1.0
  H  H12  1  0.858  0.303  0.369  1.0
  H  H13  1  0.312  0.858  0.368  1.0
  H  H14  1  0.940  0.931  0.256  1.0
  H  H15  1  0.069  0.060  0.744  1.0
  H  H16  1  0.953  0.912  0.719  1.0
  H  H17  1  0.088  0.047  0.281  1.0
  H  H18  1  0.284  0.542  0.631  1.0
  H  H19  1  0.543  0.273  0.630  1.0
  H  H20  1  0.727  0.457  0.370  1.0
  H  H21  1  0.458  0.716  0.369  1.0
  S  S22  1  0.787  0.790  0.476  1.0
  S  S23  1  0.210  0.213  0.524  1.0
  S  S24  1  0.296  0.302  0.008  1.0
  S  S25  1  0.698  0.704  0.992  1.0
  O  O26  1  0.249  0.649  0.679  1.0
  O  O27  1  0.649  0.240  0.684  1.0
  O  O28  1  0.760  0.351  0.316  1.0
  O  O29  1  0.351  0.751  0.321  1.0
  O  O30  1  0.825  0.820  0.987  1.0
  O  O31  1  0.180  0.175  0.013  1.0
  O  O32  1  0.353  0.378  0.149  1.0
  O  O33  1  0.622  0.647  0.851  1.0
  O  O34  1  0.195  0.805  0.000  1.0
  O  O35  1  0.814  0.186  0.000  1.0
  O  O36  1  0.988  0.000  0.790  1.0
  O  O37  1  1.000  0.012  0.210  1.0
  O  O38  1  0.230  0.448  0.928  1.0
  O  O39  1  0.457  0.238  0.947  1.0
  O  O40  1  0.762  0.543  0.053  1.0
  O  O41  1  0.552  0.770  0.072  1.0
  O  O42  1  0.347  0.329  0.528  1.0
  O  O43  1  0.671  0.653  0.472  1.0
  O  O44  1  0.861  0.788  0.342  1.0
  O  O45  1  0.212  0.139  0.658  1.0
  O  O46  1  0.923  0.760  0.589  1.0
  O  O47  1  0.693  0.952  0.509  1.0
  O  O48  1  0.048  0.307  0.491  1.0
  O  O49  1  0.240  0.077  0.411  1.0
[/CIF]
.