data_CaMg4Sb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.01
_cell_length_b   6.01
_cell_length_c   6.01
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CaMg4Sb
_chemical_formula_sum   'Ca1 Mg4 Sb1'
_cell_volume   153.74
_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
  Ca  Ca0  1  0.0  0.0  0.0  1.0
  Mg  Mg1  1  0.31  0.31  0.19  1.0
  Mg  Mg2  1  0.31  0.19  0.31  1.0
  Mg  Mg3  1  0.19  0.31  0.31  1.0
  Mg  Mg4  1  0.19  0.19  0.19  1.0
  Sb  Sb5  1  0.38  0.38  0.38  1.0

data_CaMg4Sb
_symmetry_space_group_name_H-M   R3m
_cell_length_a   6.01
_cell_length_b   6.01
_cell_length_c   14.73
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   CaMg4Sb
_chemical_formula_sum   'Ca3 Mg12 Sb3'
_cell_volume   461.23
_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
  Ca  Ca0  3  0.0  0.0  0.0  1.0
  Mg  Mg1  9  0.08  0.04  0.73  1.0
  Mg  Mg2  3  0.0  0.0  0.81  1.0
  Sb  Sb3  3  0.0  0.0  0.62  1.0

Ca Mg Mg Mg Mg Sb
Ca Mg Mg Mg Mg Sb 0 3 o - o 0 3 - o o 0 3 o o - 0 5 - o o 0 5 o - o 0 5 o o - 0 2 - o o 0 2 o - o 0 2 o o - 0 1 - o o 0 1 o - o 0 1 o o - 0 4 o o o 1 2 o o o 1 3 o o o 1 4 o o o 1 5 o o o 2 3 o o o 2 4 o o o 2 5 o o o 3 4 o o o 3 5 o o o 
CaMg4Sb is Copper structured and crystallizes in the trigonal R3m space group. The structure is zero-dimensional and consists of three CaMg4Sb clusters. Ca(1) is bonded in a distorted single-bond geometry to one Mg(2) atom. The Ca(1)-Mg(2) bond length is 2.80 Å. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 2-coordinate geometry to one Mg(2), two equivalent Mg(1), and one Sb(1) atom. The Mg(1)-Mg(2) bond length is 1.28 Å. Both Mg(1)-Mg(1) bond lengths are 0.74 Å. The Mg(1)-Sb(1) bond length is 1.61 Å. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to one Ca(1) and three equivalent Mg(1) atoms. Sb(1) is bonded in a 3-coordinate geometry to three equivalent Mg(1) atoms.