The material described by Mg6Cu16Si7 crystallizes in the cubic Fm-3m space group. Mg(1) is bonded in a 12-coordinate geometry to four equivalent Cu(1), four equivalent Cu(2), and four equivalent Si(2) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(2) is bonded in a 12-coordinate geometry to three equivalent Mg(1), three equivalent Cu(1), three equivalent Cu(2), and three equivalent Si(2) atoms. In the second Cu site, Cu(1) is bonded in a 13-coordinate geometry to three equivalent Mg(1), three equivalent Cu(1), three equivalent Cu(2), one Si(1), and three equivalent Si(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(2) is bonded to four equivalent Mg(1), four equivalent Cu(1), and four equivalent Cu(2) atoms to form a mixture of corner and face-sharing SiMg4Cu8 cuboctahedra. In the second Si site, Si(1) is bonded in a body-centered cubic geometry to eight equivalent Cu(1) atoms. is represented by the CIF file [CIF]
data_Mg6Cu16Si7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.187
_cell_length_b   8.187
_cell_length_c   8.187
_cell_angle_alpha   60.002
_cell_angle_beta   60.002
_cell_angle_gamma   60.002
_symmetry_Int_Tables_number   1
_cell_volume   388.059
_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  0.297  0.703  0.297  1.0
  Mg  Mg1  1  0.297  0.703  0.703  1.0
  Mg  Mg2  1  0.703  0.297  0.297  1.0
  Mg  Mg3  1  0.703  0.703  0.297  1.0
  Mg  Mg4  1  0.297  0.297  0.703  1.0
  Mg  Mg5  1  0.703  0.297  0.703  1.0
  Cu  Cu6  1  0.120  0.120  0.120  1.0
  Cu  Cu7  1  0.360  0.880  0.880  1.0
  Cu  Cu8  1  0.880  0.360  0.880  1.0
  Cu  Cu9  1  0.880  0.880  0.360  1.0
  Cu  Cu10  1  0.120  0.640  0.120  1.0
  Cu  Cu11  1  0.120  0.120  0.640  1.0
  Cu  Cu12  1  0.640  0.120  0.120  1.0
  Cu  Cu13  1  0.880  0.880  0.880  1.0
  Cu  Cu14  1  0.332  0.332  0.332  1.0
  Cu  Cu15  1  0.996  0.668  0.668  1.0
  Cu  Cu16  1  0.668  0.996  0.668  1.0
  Cu  Cu17  1  0.668  0.668  0.996  1.0
  Cu  Cu18  1  0.332  0.004  0.332  1.0
  Cu  Cu19  1  0.332  0.332  0.004  1.0
  Cu  Cu20  1  0.004  0.332  0.332  1.0
  Cu  Cu21  1  0.668  0.668  0.668  1.0
  Si  Si22  1  0.000  1.000  1.000  1.0
  Si  Si23  1  1.000  0.500  1.000  1.0
  Si  Si24  1  0.500  1.000  1.000  1.0
  Si  Si25  1  1.000  0.500  0.500  1.0
  Si  Si26  1  0.500  0.000  0.500  1.0
  Si  Si27  1  1.000  1.000  0.500  1.0
  Si  Si28  1  0.500  0.500  1.000  1.0
[/CIF]
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The material described by Mg6Cu16Si7 crystallizes in the cubic Fm-3m space group. Mg(1) is bonded in a 12-coordinate geometry to four equivalent Cu(1), four equivalent Cu(2), and four equivalent Si(2) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(2) is bonded in a 12-coordinate geometry to three equivalent Mg(1), three equivalent Cu(1), three equivalent Cu(2), and three equivalent Si(2) atoms. In the second Cu site, Cu(1) is bonded in a 13-coordinate geometry to three equivalent Mg(1), three equivalent Cu(1), three equivalent Cu(2), one Si(1), and three equivalent Si(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(2) is bonded to four equivalent Mg(1), four equivalent Cu(1), and four equivalent Cu(2) atoms to form a mixture of corner and face-sharing SiMg4Cu8 cuboctahedra. In the second Si site, Si(1) is bonded in a body-centered cubic geometry to eight equivalent Cu(1) atoms. is represented by the CIF file [CIF]
data_Mg6Cu16Si7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.187
_cell_length_b   8.187
_cell_length_c   8.187
_cell_angle_alpha   60.002
_cell_angle_beta   60.002
_cell_angle_gamma   60.002
_symmetry_Int_Tables_number   1
_cell_volume   388.059
_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  0.297  0.703  0.297  1.0
  Mg  Mg1  1  0.297  0.703  0.703  1.0
  Mg  Mg2  1  0.703  0.297  0.297  1.0
  Mg  Mg3  1  0.703  0.703  0.297  1.0
  Mg  Mg4  1  0.297  0.297  0.703  1.0
  Mg  Mg5  1  0.703  0.297  0.703  1.0
  Cu  Cu6  1  0.120  0.120  0.120  1.0
  Cu  Cu7  1  0.360  0.880  0.880  1.0
  Cu  Cu8  1  0.880  0.360  0.880  1.0
  Cu  Cu9  1  0.880  0.880  0.360  1.0
  Cu  Cu10  1  0.120  0.640  0.120  1.0
  Cu  Cu11  1  0.120  0.120  0.640  1.0
  Cu  Cu12  1  0.640  0.120  0.120  1.0
  Cu  Cu13  1  0.880  0.880  0.880  1.0
  Cu  Cu14  1  0.332  0.332  0.332  1.0
  Cu  Cu15  1  0.996  0.668  0.668  1.0
  Cu  Cu16  1  0.668  0.996  0.668  1.0
  Cu  Cu17  1  0.668  0.668  0.996  1.0
  Cu  Cu18  1  0.332  0.004  0.332  1.0
  Cu  Cu19  1  0.332  0.332  0.004  1.0
  Cu  Cu20  1  0.004  0.332  0.332  1.0
  Cu  Cu21  1  0.668  0.668  0.668  1.0
  Si  Si22  1  0.000  1.000  1.000  1.0
  Si  Si23  1  1.000  0.500  1.000  1.0
  Si  Si24  1  0.500  1.000  1.000  1.0
  Si  Si25  1  1.000  0.500  0.500  1.0
  Si  Si26  1  0.500  0.000  0.500  1.0
  Si  Si27  1  1.000  1.000  0.500  1.0
  Si  Si28  1  0.500  0.500  1.000  1.0
[/CIF]
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