The structure described by K3MgNbO8 crystallizes in the monoclinic Cm space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 9-coordinate geometry to one Mg(1), one O(1), one O(3), one O(4), one O(6), two equivalent O(2), and two equivalent O(5) atoms. In the second K site, K(2) is bonded in a 8-coordinate geometry to one O(1), one O(3), one O(4), one O(6), two equivalent O(2), and two equivalent O(5) atoms. Mg(1) is bonded in a 5-coordinate geometry to two equivalent K(1), one O(1), one O(3), one O(6), and two equivalent O(5) atoms. Nb(1) is bonded in a 8-coordinate geometry to one O(1), one O(3), one O(4), one O(6), two equivalent O(2), and two equivalent O(5) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal bipyramidal geometry to one K(2), two equivalent K(1), one Mg(1), and one Nb(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one K(2), two equivalent K(1), one Nb(1), and one O(5) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one K(2), two equivalent K(1), one Mg(1), one Nb(1), and one O(4) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one K(2), two equivalent K(1), one Nb(1), and one O(3) atom. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one K(2), two equivalent K(1), one Mg(1), one Nb(1), and one O(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one K(2), two equivalent K(1), one Mg(1), and one Nb(1) atom. is represented by the CIF card [CIF]
data_K3MgNbO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.955
_cell_length_b   6.749
_cell_length_c   6.749
_cell_angle_alpha   98.668
_cell_angle_beta   112.972
_cell_angle_gamma   112.972
_symmetry_Int_Tables_number   1
_cell_volume   214.724
_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
  K  K0  1  0.507  0.356  0.767  1.0
  K  K1  1  0.507  0.767  0.356  1.0
  K  K2  1  0.945  0.455  0.455  1.0
  Mg  Mg3  1  0.365  0.917  0.917  1.0
  Nb  Nb4  1  0.929  0.982  0.982  1.0
  O  O5  1  0.521  0.762  0.762  1.0
  O  O6  1  0.003  0.156  0.763  1.0
  O  O7  1  0.003  0.763  0.156  1.0
  O  O8  1  0.410  0.177  0.177  1.0
  O  O9  1  0.263  0.264  0.264  1.0
  O  O10  1  0.038  0.686  0.953  1.0
  O  O11  1  0.038  0.953  0.686  1.0
  O  O12  1  0.764  0.114  0.114  1.0
[/CIF]
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The structure described by K3MgNbO8 crystallizes in the monoclinic Cm space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 9-coordinate geometry to one Mg(1), one O(1), one O(3), one O(4), one O(6), two equivalent O(2), and two equivalent O(5) atoms. In the second K site, K(2) is bonded in a 8-coordinate geometry to one O(1), one O(3), one O(4), one O(6), two equivalent O(2), and two equivalent O(5) atoms. Mg(1) is bonded in a 5-coordinate geometry to two equivalent K(1), one O(1), one O(3), one O(6), and two equivalent O(5) atoms. Nb(1) is bonded in a 8-coordinate geometry to one O(1), one O(3), one O(4), one O(6), two equivalent O(2), and two equivalent O(5) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal bipyramidal geometry to one K(2), two equivalent K(1), one Mg(1), and one Nb(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one K(2), two equivalent K(1), one Nb(1), and one O(5) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one K(2), two equivalent K(1), one Mg(1), one Nb(1), and one O(4) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one K(2), two equivalent K(1), one Nb(1), and one O(3) atom. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one K(2), two equivalent K(1), one Mg(1), one Nb(1), and one O(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one K(2), two equivalent K(1), one Mg(1), and one Nb(1) atom. is represented by the CIF card [CIF]
data_K3MgNbO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.955
_cell_length_b   6.749
_cell_length_c   6.749
_cell_angle_alpha   98.668
_cell_angle_beta   112.972
_cell_angle_gamma   112.972
_symmetry_Int_Tables_number   1
_cell_volume   214.724
_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
  K  K0  1  0.507  0.356  0.767  1.0
  K  K1  1  0.507  0.767  0.356  1.0
  K  K2  1  0.945  0.455  0.455  1.0
  Mg  Mg3  1  0.365  0.917  0.917  1.0
  Nb  Nb4  1  0.929  0.982  0.982  1.0
  O  O5  1  0.521  0.762  0.762  1.0
  O  O6  1  0.003  0.156  0.763  1.0
  O  O7  1  0.003  0.763  0.156  1.0
  O  O8  1  0.410  0.177  0.177  1.0
  O  O9  1  0.263  0.264  0.264  1.0
  O  O10  1  0.038  0.686  0.953  1.0
  O  O11  1  0.038  0.953  0.686  1.0
  O  O12  1  0.764  0.114  0.114  1.0
[/CIF]
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