The material described by Mg6SiBi crystallizes in the orthorhombic Amm2 space group. There are eight inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Si(1), and two equivalent Bi(1) atoms to form distorted MgMg8Si2Bi2 cuboctahedra that share corners with four equivalent Si(1)Mg10Bi2 cuboctahedra; corners with four equivalent Bi(1)Mg10Si2 cuboctahedra; corners with ten Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Mg(1)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Si(1)Mg10Bi2 cuboctahedra; edges with two equivalent Bi(1)Mg10Si2 cuboctahedra; edges with four equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with four equivalent Mg(3)Mg10Si2 cuboctahedra; edges with four equivalent Mg(2)Mg8Si2Bi2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mg(3)Mg10Si2 cuboctahedra; faces with two equivalent Si(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Si2 cuboctahedra; faces with four Mg(1,1)Mg8Si2Bi2 cuboctahedra; and faces with eight Mg(2,2)Mg8Si2Bi2 cuboctahedra. In the second Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Si(1), and two equivalent Bi(1) atoms to form distorted MgMg8Si2Bi2 cuboctahedra that share corners with four equivalent Si(1)Mg10Bi2 cuboctahedra; corners with four equivalent Bi(1)Mg10Si2 cuboctahedra; corners with ten Mg(1,1)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Mg(1)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Si(1)Mg10Bi2 cuboctahedra; edges with two equivalent Bi(1)Mg10Si2 cuboctahedra; edges with four equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with four equivalent Mg(3)Mg10Si2 cuboctahedra; edges with four equivalent Mg(2)Mg8Si2Bi2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mg(3)Mg10Si2 cuboctahedra; faces with two equivalent Si(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Si2 cuboctahedra; faces with four Mg(1,1)Mg8Si2Bi2 cuboctahedra; and faces with eight Mg(2,2)Mg8Si2Bi2 cuboctahedra. In the third Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Si(1), and two equivalent Bi(1) atoms to form distorted MgMg8Si2Bi2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Bi2 cuboctahedra; corners with four equivalent Mg(3)Mg10Si2 cuboctahedra; corners with ten Mg(2,2)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with two equivalent Mg(3)Mg10Si2 cuboctahedra; edges with two equivalent Mg(2)Mg8Si2Bi2 cuboctahedra; edges with four equivalent Mg(1)Mg8Si2Bi2 cuboctahedra; edges with four equivalent Si(1)Mg10Bi2 cuboctahedra; edges with four equivalent Bi(1)Mg10Si2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mg(3)Mg10Si2 cuboctahedra; faces with two equivalent Si(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Si2 cuboctahedra; faces with four equivalent Mg(2)Mg8Si2Bi2 cuboctahedra; and faces with eight Mg(1,1)Mg8Si2Bi2 cuboctahedra. In the fourth Mg site, Mg(3) is bonded to two equivalent Mg(4); four Mg(1,1); four Mg(2,2,2); and two equivalent Si(1) atoms to form distorted MgMg10Si2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Bi2 cuboctahedra; corners with six equivalent Mg(3)Mg10Si2 cuboctahedra; corners with eight Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with four Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; edges with four equivalent Si(1)Mg10Bi2 cuboctahedra; edges with eight Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mg(3)Mg10Si2 cuboctahedra; faces with two equivalent Si(1)Mg10Bi2 cuboctahedra; faces with four Mg(1,1)Mg8Si2Bi2 cuboctahedra; faces with four Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; and faces with six equivalent Bi(1)Mg10Si2 cuboctahedra. In the fifth Mg site, Mg(4) is bonded to two equivalent Mg(3); four Mg(1,1); four Mg(2,2,2); and two equivalent Bi(1) atoms to form distorted MgMg10Bi2 cuboctahedra that share corners with four equivalent Mg(3)Mg10Si2 cuboctahedra; corners with six equivalent Mg(4)Mg10Bi2 cuboctahedra; corners with eight Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Mg(3)Mg10Si2 cuboctahedra; edges with four Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; edges with four equivalent Bi(1)Mg10Si2 cuboctahedra; edges with eight Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mg(3)Mg10Si2 cuboctahedra; faces with two equivalent Bi(1)Mg10Si2 cuboctahedra; faces with four Mg(1,1)Mg8Si2Bi2 cuboctahedra; faces with four Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; and faces with six equivalent Si(1)Mg10Bi2 cuboctahedra. In the sixth Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Si(1), and two equivalent Bi(1) atoms to form distorted MgMg8Si2Bi2 cuboctahedra that share corners with four equivalent Si(1)Mg10Bi2 cuboctahedra; corners with four equivalent Bi(1)Mg10Si2 cuboctahedra; corners with ten Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Mg(1)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Si(1)Mg10Bi2 cuboctahedra; edges with two equivalent Bi(1)Mg10Si2 cuboctahedra; edges with four equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with four equivalent Mg(3)Mg10Si2 cuboctahedra; edges with four equivalent Mg(2)Mg8Si2Bi2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mg(3)Mg10Si2 cuboctahedra; faces with two equivalent Si(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Si2 cuboctahedra; faces with four Mg(1,1)Mg8Si2Bi2 cuboctahedra; and faces with eight Mg(2,2,2)Mg8Si2Bi2 cuboctahedra. In the seventh Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Si(1), and two equivalent Bi(1) atoms to form distorted MgMg8Si2Bi2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Bi2 cuboctahedra; corners with four equivalent Mg(3)Mg10Si2 cuboctahedra; corners with ten Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with two equivalent Mg(3)Mg10Si2 cuboctahedra; edges with two equivalent Mg(2)Mg8Si2Bi2 cuboctahedra; edges with four equivalent Mg(1)Mg8Si2Bi2 cuboctahedra; edges with four equivalent Si(1)Mg10Bi2 cuboctahedra; edges with four equivalent Bi(1)Mg10Si2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mg(3)Mg10Si2 cuboctahedra; faces with two equivalent Si(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Si2 cuboctahedra; faces with four Mg(2,2)Mg8Si2Bi2 cuboctahedra; and faces with eight Mg(1,1)Mg8Si2Bi2 cuboctahedra. In the eighth Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Si(1), and two equivalent Bi(1) atoms to form distorted MgMg8Si2Bi2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Bi2 cuboctahedra; corners with four equivalent Mg(3)Mg10Si2 cuboctahedra; corners with ten Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with two equivalent Mg(3)Mg10Si2 cuboctahedra; edges with two equivalent Mg(2)Mg8Si2Bi2 cuboctahedra; edges with four equivalent Mg(1)Mg8Si2Bi2 cuboctahedra; edges with four equivalent Si(1)Mg10Bi2 cuboctahedra; edges with four equivalent Bi(1)Mg10Si2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mg(3)Mg10Si2 cuboctahedra; faces with two equivalent Si(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Si2 cuboctahedra; faces with four Mg(2,2)Mg8Si2Bi2 cuboctahedra; and faces with eight Mg(1,1,1)Mg8Si2Bi2 cuboctahedra. Si(1) is bonded to two equivalent Mg(3); four Mg(1,1,1); four Mg(2,2); and two equivalent Bi(1) atoms to form SiMg10Bi2 cuboctahedra that share corners with four equivalent Bi(1)Mg10Si2 cuboctahedra; corners with six equivalent Si(1)Mg10Bi2 cuboctahedra; corners with eight Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Bi(1)Mg10Si2 cuboctahedra; edges with four equivalent Mg(3)Mg10Si2 cuboctahedra; edges with four Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; edges with eight Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; faces with two equivalent Mg(3)Mg10Si2 cuboctahedra; faces with two equivalent Si(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Si2 cuboctahedra; faces with four Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; faces with four Mg(2,2)Mg8Si2Bi2 cuboctahedra; and faces with six equivalent Mg(4)Mg10Bi2 cuboctahedra. Bi(1) is bonded to two equivalent Mg(4); four Mg(1,1,1); four equivalent Mg(2); and two equivalent Si(1) atoms to form BiMg10Si2 cuboctahedra that share corners with four equivalent Si(1)Mg10Bi2 cuboctahedra; corners with six equivalent Bi(1)Mg10Si2 cuboctahedra; corners with eight Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Si(1)Mg10Bi2 cuboctahedra; edges with four equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with four Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; edges with eight Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Si(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Si2 cuboctahedra; faces with four Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; faces with four equivalent Mg(2)Mg8Si2Bi2 cuboctahedra; and faces with six equivalent Mg(3)Mg10Si2 cuboctahedra. is represented by the CIF card [CIF]
data_Mg6SiBi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.199
_cell_length_b   6.340
_cell_length_c   6.340
_cell_angle_alpha   119.251
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   182.346
_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
  Bi  Bi0  1  0.500  0.667  0.333  1.0
  Mg  Mg1  1  0.500  0.166  0.334  1.0
  Mg  Mg2  1  0.500  0.666  0.834  1.0
  Mg  Mg3  1  1.000  0.323  0.156  1.0
  Mg  Mg4  1  0.000  0.844  0.677  1.0
  Mg  Mg5  1  0.000  0.330  0.670  1.0
  Mg  Mg6  1  0.000  0.836  0.164  1.0
  Si  Si7  1  0.500  0.168  0.832  1.0
[/CIF]
.
The material described by Mg6SiBi crystallizes in the orthorhombic Amm2 space group. There are eight inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Si(1), and two equivalent Bi(1) atoms to form distorted MgMg8Si2Bi2 cuboctahedra that share corners with four equivalent Si(1)Mg10Bi2 cuboctahedra; corners with four equivalent Bi(1)Mg10Si2 cuboctahedra; corners with ten Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Mg(1)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Si(1)Mg10Bi2 cuboctahedra; edges with two equivalent Bi(1)Mg10Si2 cuboctahedra; edges with four equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with four equivalent Mg(3)Mg10Si2 cuboctahedra; edges with four equivalent Mg(2)Mg8Si2Bi2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mg(3)Mg10Si2 cuboctahedra; faces with two equivalent Si(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Si2 cuboctahedra; faces with four Mg(1,1)Mg8Si2Bi2 cuboctahedra; and faces with eight Mg(2,2)Mg8Si2Bi2 cuboctahedra. In the second Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Si(1), and two equivalent Bi(1) atoms to form distorted MgMg8Si2Bi2 cuboctahedra that share corners with four equivalent Si(1)Mg10Bi2 cuboctahedra; corners with four equivalent Bi(1)Mg10Si2 cuboctahedra; corners with ten Mg(1,1)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Mg(1)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Si(1)Mg10Bi2 cuboctahedra; edges with two equivalent Bi(1)Mg10Si2 cuboctahedra; edges with four equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with four equivalent Mg(3)Mg10Si2 cuboctahedra; edges with four equivalent Mg(2)Mg8Si2Bi2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mg(3)Mg10Si2 cuboctahedra; faces with two equivalent Si(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Si2 cuboctahedra; faces with four Mg(1,1)Mg8Si2Bi2 cuboctahedra; and faces with eight Mg(2,2)Mg8Si2Bi2 cuboctahedra. In the third Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Si(1), and two equivalent Bi(1) atoms to form distorted MgMg8Si2Bi2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Bi2 cuboctahedra; corners with four equivalent Mg(3)Mg10Si2 cuboctahedra; corners with ten Mg(2,2)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with two equivalent Mg(3)Mg10Si2 cuboctahedra; edges with two equivalent Mg(2)Mg8Si2Bi2 cuboctahedra; edges with four equivalent Mg(1)Mg8Si2Bi2 cuboctahedra; edges with four equivalent Si(1)Mg10Bi2 cuboctahedra; edges with four equivalent Bi(1)Mg10Si2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mg(3)Mg10Si2 cuboctahedra; faces with two equivalent Si(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Si2 cuboctahedra; faces with four equivalent Mg(2)Mg8Si2Bi2 cuboctahedra; and faces with eight Mg(1,1)Mg8Si2Bi2 cuboctahedra. In the fourth Mg site, Mg(3) is bonded to two equivalent Mg(4); four Mg(1,1); four Mg(2,2,2); and two equivalent Si(1) atoms to form distorted MgMg10Si2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Bi2 cuboctahedra; corners with six equivalent Mg(3)Mg10Si2 cuboctahedra; corners with eight Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with four Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; edges with four equivalent Si(1)Mg10Bi2 cuboctahedra; edges with eight Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mg(3)Mg10Si2 cuboctahedra; faces with two equivalent Si(1)Mg10Bi2 cuboctahedra; faces with four Mg(1,1)Mg8Si2Bi2 cuboctahedra; faces with four Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; and faces with six equivalent Bi(1)Mg10Si2 cuboctahedra. In the fifth Mg site, Mg(4) is bonded to two equivalent Mg(3); four Mg(1,1); four Mg(2,2,2); and two equivalent Bi(1) atoms to form distorted MgMg10Bi2 cuboctahedra that share corners with four equivalent Mg(3)Mg10Si2 cuboctahedra; corners with six equivalent Mg(4)Mg10Bi2 cuboctahedra; corners with eight Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Mg(3)Mg10Si2 cuboctahedra; edges with four Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; edges with four equivalent Bi(1)Mg10Si2 cuboctahedra; edges with eight Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mg(3)Mg10Si2 cuboctahedra; faces with two equivalent Bi(1)Mg10Si2 cuboctahedra; faces with four Mg(1,1)Mg8Si2Bi2 cuboctahedra; faces with four Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; and faces with six equivalent Si(1)Mg10Bi2 cuboctahedra. In the sixth Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Si(1), and two equivalent Bi(1) atoms to form distorted MgMg8Si2Bi2 cuboctahedra that share corners with four equivalent Si(1)Mg10Bi2 cuboctahedra; corners with four equivalent Bi(1)Mg10Si2 cuboctahedra; corners with ten Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Mg(1)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Si(1)Mg10Bi2 cuboctahedra; edges with two equivalent Bi(1)Mg10Si2 cuboctahedra; edges with four equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with four equivalent Mg(3)Mg10Si2 cuboctahedra; edges with four equivalent Mg(2)Mg8Si2Bi2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mg(3)Mg10Si2 cuboctahedra; faces with two equivalent Si(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Si2 cuboctahedra; faces with four Mg(1,1)Mg8Si2Bi2 cuboctahedra; and faces with eight Mg(2,2,2)Mg8Si2Bi2 cuboctahedra. In the seventh Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Si(1), and two equivalent Bi(1) atoms to form distorted MgMg8Si2Bi2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Bi2 cuboctahedra; corners with four equivalent Mg(3)Mg10Si2 cuboctahedra; corners with ten Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with two equivalent Mg(3)Mg10Si2 cuboctahedra; edges with two equivalent Mg(2)Mg8Si2Bi2 cuboctahedra; edges with four equivalent Mg(1)Mg8Si2Bi2 cuboctahedra; edges with four equivalent Si(1)Mg10Bi2 cuboctahedra; edges with four equivalent Bi(1)Mg10Si2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mg(3)Mg10Si2 cuboctahedra; faces with two equivalent Si(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Si2 cuboctahedra; faces with four Mg(2,2)Mg8Si2Bi2 cuboctahedra; and faces with eight Mg(1,1)Mg8Si2Bi2 cuboctahedra. In the eighth Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Si(1), and two equivalent Bi(1) atoms to form distorted MgMg8Si2Bi2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Bi2 cuboctahedra; corners with four equivalent Mg(3)Mg10Si2 cuboctahedra; corners with ten Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with two equivalent Mg(3)Mg10Si2 cuboctahedra; edges with two equivalent Mg(2)Mg8Si2Bi2 cuboctahedra; edges with four equivalent Mg(1)Mg8Si2Bi2 cuboctahedra; edges with four equivalent Si(1)Mg10Bi2 cuboctahedra; edges with four equivalent Bi(1)Mg10Si2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mg(3)Mg10Si2 cuboctahedra; faces with two equivalent Si(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Si2 cuboctahedra; faces with four Mg(2,2)Mg8Si2Bi2 cuboctahedra; and faces with eight Mg(1,1,1)Mg8Si2Bi2 cuboctahedra. Si(1) is bonded to two equivalent Mg(3); four Mg(1,1,1); four Mg(2,2); and two equivalent Bi(1) atoms to form SiMg10Bi2 cuboctahedra that share corners with four equivalent Bi(1)Mg10Si2 cuboctahedra; corners with six equivalent Si(1)Mg10Bi2 cuboctahedra; corners with eight Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Bi(1)Mg10Si2 cuboctahedra; edges with four equivalent Mg(3)Mg10Si2 cuboctahedra; edges with four Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; edges with eight Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; faces with two equivalent Mg(3)Mg10Si2 cuboctahedra; faces with two equivalent Si(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Si2 cuboctahedra; faces with four Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; faces with four Mg(2,2)Mg8Si2Bi2 cuboctahedra; and faces with six equivalent Mg(4)Mg10Bi2 cuboctahedra. Bi(1) is bonded to two equivalent Mg(4); four Mg(1,1,1); four equivalent Mg(2); and two equivalent Si(1) atoms to form BiMg10Si2 cuboctahedra that share corners with four equivalent Si(1)Mg10Bi2 cuboctahedra; corners with six equivalent Bi(1)Mg10Si2 cuboctahedra; corners with eight Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; edges with two equivalent Si(1)Mg10Bi2 cuboctahedra; edges with four equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with four Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; edges with eight Mg(2,2,2)Mg8Si2Bi2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Si(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Si2 cuboctahedra; faces with four Mg(1,1,1)Mg8Si2Bi2 cuboctahedra; faces with four equivalent Mg(2)Mg8Si2Bi2 cuboctahedra; and faces with six equivalent Mg(3)Mg10Si2 cuboctahedra. is represented by the CIF card [CIF]
data_Mg6SiBi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.199
_cell_length_b   6.340
_cell_length_c   6.340
_cell_angle_alpha   119.251
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   182.346
_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
  Bi  Bi0  1  0.500  0.667  0.333  1.0
  Mg  Mg1  1  0.500  0.166  0.334  1.0
  Mg  Mg2  1  0.500  0.666  0.834  1.0
  Mg  Mg3  1  1.000  0.323  0.156  1.0
  Mg  Mg4  1  0.000  0.844  0.677  1.0
  Mg  Mg5  1  0.000  0.330  0.670  1.0
  Mg  Mg6  1  0.000  0.836  0.164  1.0
  Si  Si7  1  0.500  0.168  0.832  1.0
[/CIF]
.