The compound described by KMg3 is alpha bismuth trifluoride structured and crystallizes in the tetragonal I4/mmm space group. K(1) is bonded to four equivalent Mg(1) and eight equivalent Mg(2) atoms to form distorted KMg12 cuboctahedra that share corners with four equivalent K(1)Mg12 cuboctahedra, corners with eight equivalent Mg(1)K4Mg8 cuboctahedra, edges with eight equivalent K(1)Mg12 cuboctahedra, faces with four equivalent K(1)Mg12 cuboctahedra, and faces with six equivalent Mg(1)K4Mg8 cuboctahedra. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to four equivalent K(1) and eight equivalent Mg(2) atoms to form MgK4Mg8 cuboctahedra that share corners with four equivalent Mg(1)K4Mg8 cuboctahedra, corners with eight equivalent K(1)Mg12 cuboctahedra, edges with eight equivalent Mg(1)K4Mg8 cuboctahedra, faces with four equivalent Mg(1)K4Mg8 cuboctahedra, and faces with six equivalent K(1)Mg12 cuboctahedra. In the second Mg site, Mg(2) is bonded in a distorted body-centered cubic geometry to four equivalent K(1) and four equivalent Mg(1) atoms. is represented by the CIF file [CIF]
data_KMg3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.666
_cell_length_b   5.666
_cell_length_c   5.666
_cell_angle_alpha   124.210
_cell_angle_beta   124.210
_cell_angle_gamma   82.851
_symmetry_Int_Tables_number   1
_cell_volume   119.441
_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  0.000  0.000  0.000  1.0
  Mg  Mg1  1  0.500  0.500  0.000  1.0
  Mg  Mg2  1  0.750  0.250  0.500  1.0
  Mg  Mg3  1  0.250  0.750  0.500  1.0
[/CIF]
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The compound described by KMg3 is alpha bismuth trifluoride structured and crystallizes in the tetragonal I4/mmm space group. K(1) is bonded to four equivalent Mg(1) and eight equivalent Mg(2) atoms to form distorted KMg12 cuboctahedra that share corners with four equivalent K(1)Mg12 cuboctahedra, corners with eight equivalent Mg(1)K4Mg8 cuboctahedra, edges with eight equivalent K(1)Mg12 cuboctahedra, faces with four equivalent K(1)Mg12 cuboctahedra, and faces with six equivalent Mg(1)K4Mg8 cuboctahedra. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to four equivalent K(1) and eight equivalent Mg(2) atoms to form MgK4Mg8 cuboctahedra that share corners with four equivalent Mg(1)K4Mg8 cuboctahedra, corners with eight equivalent K(1)Mg12 cuboctahedra, edges with eight equivalent Mg(1)K4Mg8 cuboctahedra, faces with four equivalent Mg(1)K4Mg8 cuboctahedra, and faces with six equivalent K(1)Mg12 cuboctahedra. In the second Mg site, Mg(2) is bonded in a distorted body-centered cubic geometry to four equivalent K(1) and four equivalent Mg(1) atoms. is represented by the CIF file [CIF]
data_KMg3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.666
_cell_length_b   5.666
_cell_length_c   5.666
_cell_angle_alpha   124.210
_cell_angle_beta   124.210
_cell_angle_gamma   82.851
_symmetry_Int_Tables_number   1
_cell_volume   119.441
_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  0.000  0.000  0.000  1.0
  Mg  Mg1  1  0.500  0.500  0.000  1.0
  Mg  Mg2  1  0.750  0.250  0.500  1.0
  Mg  Mg3  1  0.250  0.750  0.500  1.0
[/CIF]
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