The material described by KMg6Nb crystallizes in the hexagonal P-6m2 space group. K(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form KMg12 cuboctahedra that share corners with six equivalent K(1)Mg12 cuboctahedra, edges with twelve equivalent Mg(2)K2Mg8Nb2 cuboctahedra, faces with two equivalent K(1)Mg12 cuboctahedra, faces with six equivalent Mg(2)K2Mg8Nb2 cuboctahedra, and faces with six equivalent Nb(1)Mg12 cuboctahedra. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 10-coordinate geometry to two equivalent K(1), two equivalent Mg(1), four equivalent Mg(2), and two equivalent Nb(1) atoms. In the second Mg site, Mg(2) is bonded to two equivalent K(1), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Nb(1) atoms to form distorted MgK2Mg8Nb2 cuboctahedra that share corners with four equivalent Nb(1)Mg12 cuboctahedra, corners with fourteen equivalent Mg(2)K2Mg8Nb2 cuboctahedra, edges with two equivalent Nb(1)Mg12 cuboctahedra, edges with four equivalent K(1)Mg12 cuboctahedra, edges with four equivalent Mg(2)K2Mg8Nb2 cuboctahedra, faces with two equivalent K(1)Mg12 cuboctahedra, faces with two equivalent Nb(1)Mg12 cuboctahedra, and faces with six equivalent Mg(2)K2Mg8Nb2 cuboctahedra. Nb(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form NbMg12 cuboctahedra that share corners with six equivalent Nb(1)Mg12 cuboctahedra, corners with twelve equivalent Mg(2)K2Mg8Nb2 cuboctahedra, edges with six equivalent Mg(2)K2Mg8Nb2 cuboctahedra, faces with two equivalent Nb(1)Mg12 cuboctahedra, faces with six equivalent K(1)Mg12 cuboctahedra, and faces with six equivalent Mg(2)K2Mg8Nb2 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_KMg6Nb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.509
_cell_length_b   6.509
_cell_length_c   5.124
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   188.008
_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  0.667  0.333  0.000  1.0
  Mg  Mg1  1  0.699  0.849  0.000  1.0
  Mg  Mg2  1  0.151  0.301  0.000  1.0
  Mg  Mg3  1  0.151  0.849  0.000  1.0
  Mg  Mg4  1  0.013  0.507  0.500  1.0
  Mg  Mg5  1  0.493  0.987  0.500  1.0
  Mg  Mg6  1  0.493  0.507  0.500  1.0
  Nb  Nb7  1  0.000  0.000  0.500  1.0
[/CIF]
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The material described by KMg6Nb crystallizes in the hexagonal P-6m2 space group. K(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form KMg12 cuboctahedra that share corners with six equivalent K(1)Mg12 cuboctahedra, edges with twelve equivalent Mg(2)K2Mg8Nb2 cuboctahedra, faces with two equivalent K(1)Mg12 cuboctahedra, faces with six equivalent Mg(2)K2Mg8Nb2 cuboctahedra, and faces with six equivalent Nb(1)Mg12 cuboctahedra. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 10-coordinate geometry to two equivalent K(1), two equivalent Mg(1), four equivalent Mg(2), and two equivalent Nb(1) atoms. In the second Mg site, Mg(2) is bonded to two equivalent K(1), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Nb(1) atoms to form distorted MgK2Mg8Nb2 cuboctahedra that share corners with four equivalent Nb(1)Mg12 cuboctahedra, corners with fourteen equivalent Mg(2)K2Mg8Nb2 cuboctahedra, edges with two equivalent Nb(1)Mg12 cuboctahedra, edges with four equivalent K(1)Mg12 cuboctahedra, edges with four equivalent Mg(2)K2Mg8Nb2 cuboctahedra, faces with two equivalent K(1)Mg12 cuboctahedra, faces with two equivalent Nb(1)Mg12 cuboctahedra, and faces with six equivalent Mg(2)K2Mg8Nb2 cuboctahedra. Nb(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form NbMg12 cuboctahedra that share corners with six equivalent Nb(1)Mg12 cuboctahedra, corners with twelve equivalent Mg(2)K2Mg8Nb2 cuboctahedra, edges with six equivalent Mg(2)K2Mg8Nb2 cuboctahedra, faces with two equivalent Nb(1)Mg12 cuboctahedra, faces with six equivalent K(1)Mg12 cuboctahedra, and faces with six equivalent Mg(2)K2Mg8Nb2 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_KMg6Nb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.509
_cell_length_b   6.509
_cell_length_c   5.124
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   188.008
_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  0.667  0.333  0.000  1.0
  Mg  Mg1  1  0.699  0.849  0.000  1.0
  Mg  Mg2  1  0.151  0.301  0.000  1.0
  Mg  Mg3  1  0.151  0.849  0.000  1.0
  Mg  Mg4  1  0.013  0.507  0.500  1.0
  Mg  Mg5  1  0.493  0.987  0.500  1.0
  Mg  Mg6  1  0.493  0.507  0.500  1.0
  Nb  Nb7  1  0.000  0.000  0.500  1.0
[/CIF]
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