The crystal structure described by Mg7B crystallizes in the hexagonal P-6m2 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent Mg(3) and four equivalent Mg(2) atoms. In the second Mg site, Mg(2) is bonded in a 12-coordinate geometry to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent B(1) atoms. In the third Mg site, Mg(3) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form a mixture of face and corner-sharing MgMg12 cuboctahedra. B(1) is bonded in a 6-coordinate geometry to six equivalent Mg(2) atoms. is represented by the CIF card [CIF]
data_Mg7B
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.167
_cell_length_b   6.167
_cell_length_c   4.884
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   160.837
_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
  Mg  Mg0  1  0.999  0.499  0.000  1.0
  Mg  Mg1  1  0.501  0.499  0.000  1.0
  Mg  Mg2  1  0.501  0.001  0.000  1.0
  Mg  Mg3  1  0.160  0.319  0.500  1.0
  Mg  Mg4  1  0.160  0.840  0.500  1.0
  Mg  Mg5  1  0.681  0.840  0.500  1.0
  Mg  Mg6  1  0.667  0.333  0.500  1.0
  B  B7  1  0.000  0.000  0.000  1.0
[/CIF]
.
The crystal structure described by Mg7B crystallizes in the hexagonal P-6m2 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent Mg(3) and four equivalent Mg(2) atoms. In the second Mg site, Mg(2) is bonded in a 12-coordinate geometry to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent B(1) atoms. In the third Mg site, Mg(3) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form a mixture of face and corner-sharing MgMg12 cuboctahedra. B(1) is bonded in a 6-coordinate geometry to six equivalent Mg(2) atoms. is represented by the CIF card [CIF]
data_Mg7B
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.167
_cell_length_b   6.167
_cell_length_c   4.884
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   160.837
_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
  Mg  Mg0  1  0.999  0.499  0.000  1.0
  Mg  Mg1  1  0.501  0.499  0.000  1.0
  Mg  Mg2  1  0.501  0.001  0.000  1.0
  Mg  Mg3  1  0.160  0.319  0.500  1.0
  Mg  Mg4  1  0.160  0.840  0.500  1.0
  Mg  Mg5  1  0.681  0.840  0.500  1.0
  Mg  Mg6  1  0.667  0.333  0.500  1.0
  B  B7  1  0.000  0.000  0.000  1.0
[/CIF]
.