The material described by K2Mg(SeO7)2 crystallizes in the monoclinic P2_1/c space group. K(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(5), one O(6), two equivalent O(3), and two equivalent O(4) atoms. Mg(1) is bonded in a distorted octahedral geometry to two equivalent O(5), two equivalent O(6), and two equivalent O(7) atoms. Se(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. There are seven inequivalent O sites. In the first O site, O(7) is bonded in a single-bond geometry to one Mg(1) atom. In the second O site, O(1) is bonded in a distorted water-like geometry to one K(1) and one Se(1) atom. In the third O site, O(2) is bonded in a distorted water-like geometry to one K(1) and one Se(1) atom. In the fourth O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to two equivalent K(1) and one Se(1) atom. In the fifth O site, O(4) is bonded in a distorted single-bond geometry to two equivalent K(1) and one Se(1) atom. In the sixth O site, O(5) is bonded in a bent 150 degrees geometry to one K(1) and one Mg(1) atom. In the seventh O site, O(6) is bonded in a 2-coordinate geometry to one K(1) and one Mg(1) atom. is represented by the CIF card [CIF]
data_K2Mg(SeO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.109
_cell_length_b   8.529
_cell_length_c   12.049
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   102.943
_symmetry_Int_Tables_number   1
_cell_volume   611.912
_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  0.840  0.140  0.658  1.0
  K  K1  1  0.160  0.360  0.158  1.0
  K  K2  1  0.160  0.860  0.342  1.0
  K  K3  1  0.840  0.640  0.842  1.0
  Mg  Mg4  1  0.500  0.500  0.500  1.0
  Mg  Mg5  1  0.500  0.000  0.000  1.0
  Se  Se6  1  0.250  0.907  0.650  1.0
  Se  Se7  1  0.750  0.593  0.150  1.0
  Se  Se8  1  0.750  0.093  0.350  1.0
  Se  Se9  1  0.250  0.407  0.850  1.0
  O  O10  1  0.497  0.866  0.692  1.0
  O  O11  1  0.503  0.634  0.192  1.0
  O  O12  1  0.503  0.134  0.308  1.0
  O  O13  1  0.497  0.366  0.808  1.0
  O  O14  1  0.109  0.757  0.565  1.0
  O  O15  1  0.891  0.743  0.065  1.0
  O  O16  1  0.891  0.243  0.435  1.0
  O  O17  1  0.109  0.257  0.935  1.0
  O  O18  1  0.083  0.924  0.756  1.0
  O  O19  1  0.917  0.576  0.256  1.0
  O  O20  1  0.917  0.076  0.244  1.0
  O  O21  1  0.083  0.424  0.744  1.0
  O  O22  1  0.293  0.070  0.569  1.0
  O  O23  1  0.707  0.430  0.069  1.0
  O  O24  1  0.707  0.930  0.431  1.0
  O  O25  1  0.293  0.570  0.931  1.0
  O  O26  1  0.332  0.363  0.376  1.0
  O  O27  1  0.668  0.137  0.876  1.0
  O  O28  1  0.668  0.637  0.624  1.0
  O  O29  1  0.332  0.863  0.124  1.0
  O  O30  1  0.552  0.346  0.626  1.0
  O  O31  1  0.448  0.154  0.126  1.0
  O  O32  1  0.448  0.654  0.374  1.0
  O  O33  1  0.552  0.846  0.874  1.0
  O  O34  1  0.156  0.519  0.537  1.0
  O  O35  1  0.844  0.981  0.037  1.0
  O  O36  1  0.844  0.481  0.463  1.0
  O  O37  1  0.156  0.019  0.963  1.0
[/CIF]
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The material described by K2Mg(SeO7)2 crystallizes in the monoclinic P2_1/c space group. K(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(5), one O(6), two equivalent O(3), and two equivalent O(4) atoms. Mg(1) is bonded in a distorted octahedral geometry to two equivalent O(5), two equivalent O(6), and two equivalent O(7) atoms. Se(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. There are seven inequivalent O sites. In the first O site, O(7) is bonded in a single-bond geometry to one Mg(1) atom. In the second O site, O(1) is bonded in a distorted water-like geometry to one K(1) and one Se(1) atom. In the third O site, O(2) is bonded in a distorted water-like geometry to one K(1) and one Se(1) atom. In the fourth O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to two equivalent K(1) and one Se(1) atom. In the fifth O site, O(4) is bonded in a distorted single-bond geometry to two equivalent K(1) and one Se(1) atom. In the sixth O site, O(5) is bonded in a bent 150 degrees geometry to one K(1) and one Mg(1) atom. In the seventh O site, O(6) is bonded in a 2-coordinate geometry to one K(1) and one Mg(1) atom. is represented by the CIF card [CIF]
data_K2Mg(SeO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.109
_cell_length_b   8.529
_cell_length_c   12.049
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   102.943
_symmetry_Int_Tables_number   1
_cell_volume   611.912
_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  0.840  0.140  0.658  1.0
  K  K1  1  0.160  0.360  0.158  1.0
  K  K2  1  0.160  0.860  0.342  1.0
  K  K3  1  0.840  0.640  0.842  1.0
  Mg  Mg4  1  0.500  0.500  0.500  1.0
  Mg  Mg5  1  0.500  0.000  0.000  1.0
  Se  Se6  1  0.250  0.907  0.650  1.0
  Se  Se7  1  0.750  0.593  0.150  1.0
  Se  Se8  1  0.750  0.093  0.350  1.0
  Se  Se9  1  0.250  0.407  0.850  1.0
  O  O10  1  0.497  0.866  0.692  1.0
  O  O11  1  0.503  0.634  0.192  1.0
  O  O12  1  0.503  0.134  0.308  1.0
  O  O13  1  0.497  0.366  0.808  1.0
  O  O14  1  0.109  0.757  0.565  1.0
  O  O15  1  0.891  0.743  0.065  1.0
  O  O16  1  0.891  0.243  0.435  1.0
  O  O17  1  0.109  0.257  0.935  1.0
  O  O18  1  0.083  0.924  0.756  1.0
  O  O19  1  0.917  0.576  0.256  1.0
  O  O20  1  0.917  0.076  0.244  1.0
  O  O21  1  0.083  0.424  0.744  1.0
  O  O22  1  0.293  0.070  0.569  1.0
  O  O23  1  0.707  0.430  0.069  1.0
  O  O24  1  0.707  0.930  0.431  1.0
  O  O25  1  0.293  0.570  0.931  1.0
  O  O26  1  0.332  0.363  0.376  1.0
  O  O27  1  0.668  0.137  0.876  1.0
  O  O28  1  0.668  0.637  0.624  1.0
  O  O29  1  0.332  0.863  0.124  1.0
  O  O30  1  0.552  0.346  0.626  1.0
  O  O31  1  0.448  0.154  0.126  1.0
  O  O32  1  0.448  0.654  0.374  1.0
  O  O33  1  0.552  0.846  0.874  1.0
  O  O34  1  0.156  0.519  0.537  1.0
  O  O35  1  0.844  0.981  0.037  1.0
  O  O36  1  0.844  0.481  0.463  1.0
  O  O37  1  0.156  0.019  0.963  1.0
[/CIF]
.