The material described by MnH8SeO8H2O crystallizes in the triclinic P-1 space group. The structure consists of two water molecules inside a MnH8SeO8 framework. In the MnH8SeO8 framework, there are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(1), two equivalent O(5), and two equivalent O(6) atoms to form MnO6 octahedra that share corners with two equivalent Se(1)O4 tetrahedra. In the second Mn site, Mn(2) is bonded to two equivalent O(2), two equivalent O(7), and two equivalent O(8) atoms to form MnO6 octahedra that share corners with two equivalent Se(1)O4 tetrahedra. 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(5) atom. In the third H site, H(3) is bonded in a single-bond geometry to one O(6) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(6) atom. In the fifth H site, H(5) is bonded in a single-bond geometry to one O(3) 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(3) and one O(8) atom. In the eighth H site, H(8) is bonded in a single-bond geometry to one O(8) atom. Se(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SeO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra and  a cornercorner with one Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles are 45°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Mn(1) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Mn(2) and one Se(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one H(5), one H(7), and one Se(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Se(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Mn(1), one H(1), and one H(2) atom. In the sixth O site, O(6) is bonded in a distorted water-like geometry to one Mn(1), one H(3), and one H(4) atom. In the seventh O site, O(7) is bonded in a distorted water-like geometry to one Mn(2), one H(5), and one H(6) atom. In the eighth O site, O(8) is bonded in a distorted water-like geometry to one Mn(2), one H(7), and one H(8) atom. is represented by the CIF card [CIF]
data_MnH10SeO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.332
_cell_length_b   6.450
_cell_length_c   11.125
_cell_angle_alpha   75.392
_cell_angle_beta   81.641
_cell_angle_gamma   70.452
_symmetry_Int_Tables_number   1
_cell_volume   413.400
_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
  Mn  Mn0  1  0.000  0.000  0.000  1.0
  Mn  Mn1  1  0.000  0.500  0.500  1.0
  H  H2  1  0.737  0.894  0.857  1.0
  H  H3  1  0.263  0.106  0.143  1.0
  H  H4  1  0.760  0.716  0.989  1.0
  H  H5  1  0.240  0.284  0.011  1.0
  H  H6  1  0.883  0.347  0.793  1.0
  H  H7  1  0.117  0.653  0.207  1.0
  H  H8  1  0.650  0.355  0.871  1.0
  H  H9  1  0.350  0.645  0.129  1.0
  H  H10  1  0.554  0.596  0.610  1.0
  H  H11  1  0.446  0.404  0.390  1.0
  H  H12  1  0.640  0.324  0.630  1.0
  H  H13  1  0.360  0.676  0.370  1.0
  H  H14  1  0.097  0.814  0.601  1.0
  H  H15  1  0.903  0.186  0.399  1.0
  H  H16  1  0.829  0.868  0.624  1.0
  H  H17  1  0.171  0.132  0.376  1.0
  H  H18  1  0.303  0.606  0.874  1.0
  H  H19  1  0.697  0.394  0.126  1.0
  H  H20  1  0.280  0.431  0.805  1.0
  H  H21  1  0.720  0.569  0.195  1.0
  Se  Se22  1  0.352  0.018  0.712  1.0
  Se  Se23  1  0.648  0.982  0.288  1.0
  O  O24  1  0.284  0.899  0.859  1.0
  O  O25  1  0.716  0.101  0.141  1.0
  O  O26  1  0.171  0.280  0.675  1.0
  O  O27  1  0.829  0.720  0.325  1.0
  O  O28  1  0.346  0.857  0.617  1.0
  O  O29  1  0.654  0.143  0.383  1.0
  O  O30  1  0.611  0.040  0.706  1.0
  O  O31  1  0.389  0.960  0.294  1.0
  O  O32  1  0.833  0.817  0.928  1.0
  O  O33  1  0.167  0.183  0.072  1.0
  O  O34  1  0.815  0.316  0.878  1.0
  O  O35  1  0.185  0.684  0.122  1.0
  O  O36  1  0.685  0.462  0.600  1.0
  O  O37  1  0.315  0.538  0.400  1.0
  O  O38  1  0.968  0.767  0.590  1.0
  O  O39  1  0.032  0.233  0.410  1.0
  O  O40  1  0.350  0.442  0.875  1.0
  O  O41  1  0.650  0.558  0.125  1.0
[/CIF]
.
The material described by MnH8SeO8H2O crystallizes in the triclinic P-1 space group. The structure consists of two water molecules inside a MnH8SeO8 framework. In the MnH8SeO8 framework, there are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(1), two equivalent O(5), and two equivalent O(6) atoms to form MnO6 octahedra that share corners with two equivalent Se(1)O4 tetrahedra. In the second Mn site, Mn(2) is bonded to two equivalent O(2), two equivalent O(7), and two equivalent O(8) atoms to form MnO6 octahedra that share corners with two equivalent Se(1)O4 tetrahedra. 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(5) atom. In the third H site, H(3) is bonded in a single-bond geometry to one O(6) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(6) atom. In the fifth H site, H(5) is bonded in a single-bond geometry to one O(3) 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(3) and one O(8) atom. In the eighth H site, H(8) is bonded in a single-bond geometry to one O(8) atom. Se(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SeO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra and  a cornercorner with one Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles are 45°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Mn(1) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Mn(2) and one Se(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one H(5), one H(7), and one Se(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Se(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Mn(1), one H(1), and one H(2) atom. In the sixth O site, O(6) is bonded in a distorted water-like geometry to one Mn(1), one H(3), and one H(4) atom. In the seventh O site, O(7) is bonded in a distorted water-like geometry to one Mn(2), one H(5), and one H(6) atom. In the eighth O site, O(8) is bonded in a distorted water-like geometry to one Mn(2), one H(7), and one H(8) atom. is represented by the CIF card [CIF]
data_MnH10SeO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.332
_cell_length_b   6.450
_cell_length_c   11.125
_cell_angle_alpha   75.392
_cell_angle_beta   81.641
_cell_angle_gamma   70.452
_symmetry_Int_Tables_number   1
_cell_volume   413.400
_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
  Mn  Mn0  1  0.000  0.000  0.000  1.0
  Mn  Mn1  1  0.000  0.500  0.500  1.0
  H  H2  1  0.737  0.894  0.857  1.0
  H  H3  1  0.263  0.106  0.143  1.0
  H  H4  1  0.760  0.716  0.989  1.0
  H  H5  1  0.240  0.284  0.011  1.0
  H  H6  1  0.883  0.347  0.793  1.0
  H  H7  1  0.117  0.653  0.207  1.0
  H  H8  1  0.650  0.355  0.871  1.0
  H  H9  1  0.350  0.645  0.129  1.0
  H  H10  1  0.554  0.596  0.610  1.0
  H  H11  1  0.446  0.404  0.390  1.0
  H  H12  1  0.640  0.324  0.630  1.0
  H  H13  1  0.360  0.676  0.370  1.0
  H  H14  1  0.097  0.814  0.601  1.0
  H  H15  1  0.903  0.186  0.399  1.0
  H  H16  1  0.829  0.868  0.624  1.0
  H  H17  1  0.171  0.132  0.376  1.0
  H  H18  1  0.303  0.606  0.874  1.0
  H  H19  1  0.697  0.394  0.126  1.0
  H  H20  1  0.280  0.431  0.805  1.0
  H  H21  1  0.720  0.569  0.195  1.0
  Se  Se22  1  0.352  0.018  0.712  1.0
  Se  Se23  1  0.648  0.982  0.288  1.0
  O  O24  1  0.284  0.899  0.859  1.0
  O  O25  1  0.716  0.101  0.141  1.0
  O  O26  1  0.171  0.280  0.675  1.0
  O  O27  1  0.829  0.720  0.325  1.0
  O  O28  1  0.346  0.857  0.617  1.0
  O  O29  1  0.654  0.143  0.383  1.0
  O  O30  1  0.611  0.040  0.706  1.0
  O  O31  1  0.389  0.960  0.294  1.0
  O  O32  1  0.833  0.817  0.928  1.0
  O  O33  1  0.167  0.183  0.072  1.0
  O  O34  1  0.815  0.316  0.878  1.0
  O  O35  1  0.185  0.684  0.122  1.0
  O  O36  1  0.685  0.462  0.600  1.0
  O  O37  1  0.315  0.538  0.400  1.0
  O  O38  1  0.968  0.767  0.590  1.0
  O  O39  1  0.032  0.233  0.410  1.0
  O  O40  1  0.350  0.442  0.875  1.0
  O  O41  1  0.650  0.558  0.125  1.0
[/CIF]
.