data_KMgCd2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.42
_cell_length_b   5.42
_cell_length_c   5.42
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   KMgCd2
_chemical_formula_sum   'K1 Mg1 Cd2'
_cell_volume   112.88
_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  K2  1  0.92  0.92  0.92  1.0
  Mg  Mg3  1  0.0  0.0  0.0  1.0
  Cd  Cd0  1  0.75  0.75  0.75  1.0
  Cd  Cd1  1  0.84  0.84  0.84  1.0

data_KMgCd2
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.42
_cell_length_b   5.42
_cell_length_c   13.29
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   KMgCd2
_chemical_formula_sum   'K3 Mg3 Cd6'
_cell_volume   338.65
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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  3  0.0  0.0  0.08  1.0
  Mg  Mg1  3  0.0  0.0  0.0  1.0
  Cd  Cd2  3  0.0  0.0  0.16  1.0
  Cd  Cd3  3  0.0  0.0  0.25  1.0

K Mg Cd Cd
K Mg Cd Cd 0 3 o o o 0 1 + + + 2 3 o o o 
KMgCd2 crystallizes in the trigonal R3m space group. K(1) is bonded in a linear geometry to one Mg(1) and one Cd(2) atom. The K(1)-Mg(1) bond length is 1.09 Å. The K(1)-Cd(2) bond length is 1.09 Å. Mg(1) is bonded in a single-bond geometry to one K(1) and three equivalent Cd(1) atoms. All Mg(1)-Cd(1) bond lengths are 3.34 Å. There are two inequivalent Cd sites. In the first Cd site, Cd(1) is bonded to three equivalent Mg(1) and one Cd(2) atom to form distorted corner-sharing CdMg3Cd tetrahedra. The Cd(1)-Cd(2) bond length is 1.09 Å. In the second Cd site, Cd(2) is bonded in a distorted linear geometry to one K(1) and one Cd(1) atom.