data_K2MgCl
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.51
_cell_length_b   10.51
_cell_length_c   10.51
_cell_angle_alpha   23.26
_cell_angle_beta   23.26
_cell_angle_gamma   23.26
_symmetry_Int_Tables_number   1
_chemical_formula_structural   K2MgCl
_chemical_formula_sum   'K2 Mg1 Cl1'
_cell_volume   158.76
_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  K1  1  0.0  0.0  0.58  1.0
  K  K2  1  0.0  0.0  0.08  1.0
  Mg  Mg3  1  0.0  0.0  0.0  1.0
  Cl  Cl0  1  0.0  0.0  0.33  1.0

data_K2MgCl
_symmetry_space_group_name_H-M   Cm
_cell_length_a   7.34
_cell_length_b   4.24
_cell_length_c   10.51
_cell_angle_alpha   90.0
_cell_angle_beta   103.46
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   K2MgCl
_chemical_formula_sum   'K4 Mg2 Cl2'
_cell_volume   317.52
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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  2  -0.0  0.0  0.92  1.0
  K  K1  2  -0.0  0.0  0.42  1.0
  Mg  Mg2  2  0.0  0.0  0.0  1.0
  Cl  Cl3  2  0.0  0.0  0.67  1.0

K K Mg Cl
K2MgCl is Cyanogen Chloride-like structured and crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two K2MgCl clusters. There are two inequivalent K sites. In the first K site, K(1) is bonded in a single-bond geometry to one Cl(1) atom. The K(1)-Cl(1) bond length is 2.63 Å. In the second K site, K(2) is bonded in a linear geometry to one Mg(1) and one Cl(1) atom. The K(2)-Mg(1) bond length is 0.82 Å. The K(2)-Cl(1) bond length is 2.63 Å. Mg(1) is bonded in a single-bond geometry to one K(2) atom. Cl(1) is bonded in a linear geometry to one K(1) and one K(2) atom.