The crystal structure described by MgMg2Cu crystallizes in the orthorhombic Pmm2 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), four equivalent Mg(3), and four equivalent Cu(1) atoms to form distorted MgMg8Cu4 cuboctahedra that share corners with four equivalent Mg(2)Mg2Cu4 cuboctahedra, corners with eight equivalent Mg(3)Mg4Cu2 cuboctahedra, corners with ten equivalent Mg(1)Mg8Cu4 cuboctahedra, corners with twelve equivalent Cu(1)Mg10 cuboctahedra, edges with two equivalent Mg(1)Mg8Cu4 cuboctahedra, edges with four equivalent Mg(3)Mg4Cu2 cuboctahedra, edges with eight equivalent Mg(2)Mg2Cu4 cuboctahedra, faces with four equivalent Mg(1)Mg8Cu4 cuboctahedra, and faces with four equivalent Cu(1)Mg10 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1) and four equivalent Cu(1) atoms to form distorted MgMg2Cu4 cuboctahedra that share corners with four equivalent Mg(2)Mg2Cu4 cuboctahedra, corners with four equivalent Mg(1)Mg8Cu4 cuboctahedra, corners with eight equivalent Mg(3)Mg4Cu2 cuboctahedra, corners with eight equivalent Cu(1)Mg10 cuboctahedra, edges with two equivalent Mg(2)Mg2Cu4 cuboctahedra, edges with four equivalent Mg(3)Mg4Cu2 cuboctahedra, edges with eight equivalent Mg(1)Mg8Cu4 cuboctahedra, and faces with two equivalent Mg(2)Mg2Cu4 cuboctahedra. In the third Mg site, Mg(3) is bonded to four equivalent Mg(1) and two equivalent Cu(1) atoms to form distorted MgMg4Cu2 cuboctahedra that share corners with four equivalent Mg(3)Mg4Cu2 cuboctahedra, corners with eight equivalent Mg(2)Mg2Cu4 cuboctahedra, corners with eight equivalent Mg(1)Mg8Cu4 cuboctahedra, corners with eight equivalent Cu(1)Mg10 cuboctahedra, edges with two equivalent Mg(3)Mg4Cu2 cuboctahedra, edges with four equivalent Mg(2)Mg2Cu4 cuboctahedra, edges with four equivalent Mg(1)Mg8Cu4 cuboctahedra, edges with four equivalent Cu(1)Mg10 cuboctahedra, and faces with two equivalent Mg(3)Mg4Cu2 cuboctahedra. Cu(1) is bonded to two equivalent Mg(3), four equivalent Mg(1), and four equivalent Mg(2) atoms to form distorted CuMg10 cuboctahedra that share corners with eight equivalent Mg(2)Mg2Cu4 cuboctahedra, corners with eight equivalent Mg(3)Mg4Cu2 cuboctahedra, corners with eight equivalent Cu(1)Mg10 cuboctahedra, corners with twelve equivalent Mg(1)Mg8Cu4 cuboctahedra, edges with two equivalent Cu(1)Mg10 cuboctahedra, edges with four equivalent Mg(3)Mg4Cu2 cuboctahedra, faces with four equivalent Mg(1)Mg8Cu4 cuboctahedra, and faces with four equivalent Cu(1)Mg10 cuboctahedra. is represented by the CIF card [CIF]
data_Mg3Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.056
_cell_length_b   4.758
_cell_length_c   5.187
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   75.432
_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  0.000  0.000  0.668  1.0
  Mg  Mg1  1  0.000  0.500  0.323  1.0
  Mg  Mg2  1  0.500  0.500  0.844  1.0
  Cu  Cu3  1  0.500  0.000  0.165  1.0
[/CIF]
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The crystal structure described by MgMg2Cu crystallizes in the orthorhombic Pmm2 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), four equivalent Mg(3), and four equivalent Cu(1) atoms to form distorted MgMg8Cu4 cuboctahedra that share corners with four equivalent Mg(2)Mg2Cu4 cuboctahedra, corners with eight equivalent Mg(3)Mg4Cu2 cuboctahedra, corners with ten equivalent Mg(1)Mg8Cu4 cuboctahedra, corners with twelve equivalent Cu(1)Mg10 cuboctahedra, edges with two equivalent Mg(1)Mg8Cu4 cuboctahedra, edges with four equivalent Mg(3)Mg4Cu2 cuboctahedra, edges with eight equivalent Mg(2)Mg2Cu4 cuboctahedra, faces with four equivalent Mg(1)Mg8Cu4 cuboctahedra, and faces with four equivalent Cu(1)Mg10 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1) and four equivalent Cu(1) atoms to form distorted MgMg2Cu4 cuboctahedra that share corners with four equivalent Mg(2)Mg2Cu4 cuboctahedra, corners with four equivalent Mg(1)Mg8Cu4 cuboctahedra, corners with eight equivalent Mg(3)Mg4Cu2 cuboctahedra, corners with eight equivalent Cu(1)Mg10 cuboctahedra, edges with two equivalent Mg(2)Mg2Cu4 cuboctahedra, edges with four equivalent Mg(3)Mg4Cu2 cuboctahedra, edges with eight equivalent Mg(1)Mg8Cu4 cuboctahedra, and faces with two equivalent Mg(2)Mg2Cu4 cuboctahedra. In the third Mg site, Mg(3) is bonded to four equivalent Mg(1) and two equivalent Cu(1) atoms to form distorted MgMg4Cu2 cuboctahedra that share corners with four equivalent Mg(3)Mg4Cu2 cuboctahedra, corners with eight equivalent Mg(2)Mg2Cu4 cuboctahedra, corners with eight equivalent Mg(1)Mg8Cu4 cuboctahedra, corners with eight equivalent Cu(1)Mg10 cuboctahedra, edges with two equivalent Mg(3)Mg4Cu2 cuboctahedra, edges with four equivalent Mg(2)Mg2Cu4 cuboctahedra, edges with four equivalent Mg(1)Mg8Cu4 cuboctahedra, edges with four equivalent Cu(1)Mg10 cuboctahedra, and faces with two equivalent Mg(3)Mg4Cu2 cuboctahedra. Cu(1) is bonded to two equivalent Mg(3), four equivalent Mg(1), and four equivalent Mg(2) atoms to form distorted CuMg10 cuboctahedra that share corners with eight equivalent Mg(2)Mg2Cu4 cuboctahedra, corners with eight equivalent Mg(3)Mg4Cu2 cuboctahedra, corners with eight equivalent Cu(1)Mg10 cuboctahedra, corners with twelve equivalent Mg(1)Mg8Cu4 cuboctahedra, edges with two equivalent Cu(1)Mg10 cuboctahedra, edges with four equivalent Mg(3)Mg4Cu2 cuboctahedra, faces with four equivalent Mg(1)Mg8Cu4 cuboctahedra, and faces with four equivalent Cu(1)Mg10 cuboctahedra. is represented by the CIF card [CIF]
data_Mg3Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.056
_cell_length_b   4.758
_cell_length_c   5.187
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   75.432
_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  0.000  0.000  0.668  1.0
  Mg  Mg1  1  0.000  0.500  0.323  1.0
  Mg  Mg2  1  0.500  0.500  0.844  1.0
  Cu  Cu3  1  0.500  0.000  0.165  1.0
[/CIF]
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