The compound described by Mg5Cu crystallizes in the hexagonal P-62m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to three equivalent Mg(1), six equivalent Mg(2), and three equivalent Cu(1) atoms to form distorted MgMg9Cu3 cuboctahedra that share corners with nine equivalent Mg(1)Mg9Cu3 cuboctahedra, corners with nine equivalent Cu(1)Mg12 cuboctahedra, edges with six equivalent Mg(1)Mg9Cu3 cuboctahedra, edges with twelve equivalent Mg(2)Mg10Cu2 cuboctahedra, faces with three equivalent Cu(1)Mg12 cuboctahedra, faces with five equivalent Mg(1)Mg9Cu3 cuboctahedra, and faces with twelve equivalent Mg(2)Mg10Cu2 cuboctahedra. In the second Mg site, Mg(2) is bonded to four equivalent Mg(1), six equivalent Mg(2), and two equivalent Cu(1) atoms to form distorted MgMg10Cu2 cuboctahedra that share corners with eighteen equivalent Mg(2)Mg10Cu2 cuboctahedra, edges with four equivalent Cu(1)Mg12 cuboctahedra, edges with six equivalent Mg(2)Mg10Cu2 cuboctahedra, edges with eight equivalent Mg(1)Mg9Cu3 cuboctahedra, faces with four equivalent Cu(1)Mg12 cuboctahedra, faces with eight equivalent Mg(2)Mg10Cu2 cuboctahedra, and faces with eight equivalent Mg(1)Mg9Cu3 cuboctahedra. Cu(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form CuMg12 cuboctahedra that share corners with eighteen equivalent Mg(1)Mg9Cu3 cuboctahedra, edges with six equivalent Cu(1)Mg12 cuboctahedra, edges with twelve equivalent Mg(2)Mg10Cu2 cuboctahedra, faces with two equivalent Cu(1)Mg12 cuboctahedra, faces with six equivalent Mg(1)Mg9Cu3 cuboctahedra, and faces with twelve equivalent Mg(2)Mg10Cu2 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg5Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.313
_cell_length_b   5.313
_cell_length_c   4.882
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   119.339
_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  0.667  0.333  0.500  1.0
  Mg  Mg1  1  0.317  0.000  0.000  1.0
  Mg  Mg2  1  0.683  0.683  0.000  1.0
  Mg  Mg3  1  0.000  0.317  0.000  1.0
  Mg  Mg4  1  0.333  0.667  0.500  1.0
  Cu  Cu5  1  0.000  0.000  0.500  1.0
[/CIF]
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The compound described by Mg5Cu crystallizes in the hexagonal P-62m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to three equivalent Mg(1), six equivalent Mg(2), and three equivalent Cu(1) atoms to form distorted MgMg9Cu3 cuboctahedra that share corners with nine equivalent Mg(1)Mg9Cu3 cuboctahedra, corners with nine equivalent Cu(1)Mg12 cuboctahedra, edges with six equivalent Mg(1)Mg9Cu3 cuboctahedra, edges with twelve equivalent Mg(2)Mg10Cu2 cuboctahedra, faces with three equivalent Cu(1)Mg12 cuboctahedra, faces with five equivalent Mg(1)Mg9Cu3 cuboctahedra, and faces with twelve equivalent Mg(2)Mg10Cu2 cuboctahedra. In the second Mg site, Mg(2) is bonded to four equivalent Mg(1), six equivalent Mg(2), and two equivalent Cu(1) atoms to form distorted MgMg10Cu2 cuboctahedra that share corners with eighteen equivalent Mg(2)Mg10Cu2 cuboctahedra, edges with four equivalent Cu(1)Mg12 cuboctahedra, edges with six equivalent Mg(2)Mg10Cu2 cuboctahedra, edges with eight equivalent Mg(1)Mg9Cu3 cuboctahedra, faces with four equivalent Cu(1)Mg12 cuboctahedra, faces with eight equivalent Mg(2)Mg10Cu2 cuboctahedra, and faces with eight equivalent Mg(1)Mg9Cu3 cuboctahedra. Cu(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form CuMg12 cuboctahedra that share corners with eighteen equivalent Mg(1)Mg9Cu3 cuboctahedra, edges with six equivalent Cu(1)Mg12 cuboctahedra, edges with twelve equivalent Mg(2)Mg10Cu2 cuboctahedra, faces with two equivalent Cu(1)Mg12 cuboctahedra, faces with six equivalent Mg(1)Mg9Cu3 cuboctahedra, and faces with twelve equivalent Mg(2)Mg10Cu2 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg5Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.313
_cell_length_b   5.313
_cell_length_c   4.882
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   119.339
_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  0.667  0.333  0.500  1.0
  Mg  Mg1  1  0.317  0.000  0.000  1.0
  Mg  Mg2  1  0.683  0.683  0.000  1.0
  Mg  Mg3  1  0.000  0.317  0.000  1.0
  Mg  Mg4  1  0.333  0.667  0.500  1.0
  Cu  Cu5  1  0.000  0.000  0.500  1.0
[/CIF]
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