The material described by Mg6GaSi crystallizes in the orthorhombic Amm2 space group. There are five 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 Ga(1), and two equivalent Si(1) atoms to form distorted MgMg8Ga2Si2 cuboctahedra that share corners with ten Mg(1,1)Mg8Ga2Si2 cuboctahedra; edges with two equivalent Mg(1)Mg8Ga2Si2 cuboctahedra; edges with four equivalent Mg(4)Mg10Ga2 cuboctahedra; edges with four equivalent Mg(3)Mg8Ga2Si2 cuboctahedra; faces with two equivalent Mg(4)Mg10Ga2 cuboctahedra; faces with four Mg(1,1)Mg8Ga2Si2 cuboctahedra; and faces with eight equivalent Mg(3)Mg8Ga2Si2 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 Ga(1), and two equivalent Si(1) atoms to form distorted MgMg8Ga2Si2 cuboctahedra that share corners with ten Mg(1,1)Mg8Ga2Si2 cuboctahedra; edges with two equivalent Mg(1)Mg8Ga2Si2 cuboctahedra; edges with four equivalent Mg(4)Mg10Ga2 cuboctahedra; edges with four equivalent Mg(3)Mg8Ga2Si2 cuboctahedra; faces with two equivalent Mg(4)Mg10Ga2 cuboctahedra; faces with four Mg(1,1)Mg8Ga2Si2 cuboctahedra; and faces with eight equivalent Mg(3)Mg8Ga2Si2 cuboctahedra. In the third Mg site, Mg(2) is bonded in a distorted linear geometry to two equivalent Mg(4); four Mg(1,1); four equivalent Mg(3); and two equivalent Si(1) atoms. In the fourth Mg site, Mg(3) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Ga(1), and two equivalent Si(1) atoms to form distorted MgMg8Ga2Si2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Ga2 cuboctahedra; corners with ten equivalent Mg(3)Mg8Ga2Si2 cuboctahedra; edges with two equivalent Mg(4)Mg10Ga2 cuboctahedra; edges with two equivalent Mg(3)Mg8Ga2Si2 cuboctahedra; edges with four equivalent Mg(1)Mg8Ga2Si2 cuboctahedra; faces with two equivalent Mg(4)Mg10Ga2 cuboctahedra; faces with four equivalent Mg(3)Mg8Ga2Si2 cuboctahedra; and faces with eight Mg(1,1)Mg8Ga2Si2 cuboctahedra. In the fifth Mg site, Mg(4) is bonded to two equivalent Mg(2); four Mg(1,1); four equivalent Mg(3); and two equivalent Ga(1) atoms to form distorted MgMg10Ga2 cuboctahedra that share corners with six equivalent Mg(4)Mg10Ga2 cuboctahedra; corners with eight equivalent Mg(3)Mg8Ga2Si2 cuboctahedra; edges with four equivalent Mg(3)Mg8Ga2Si2 cuboctahedra; edges with eight Mg(1,1)Mg8Ga2Si2 cuboctahedra; faces with two equivalent Mg(4)Mg10Ga2 cuboctahedra; faces with four Mg(1,1)Mg8Ga2Si2 cuboctahedra; and faces with four equivalent Mg(3)Mg8Ga2Si2 cuboctahedra. Ga(1) is bonded in a 10-coordinate geometry to two equivalent Mg(4); four Mg(1,1); and four equivalent Mg(3) atoms. Si(1) is bonded in a 10-coordinate geometry to two equivalent Mg(2); four Mg(1,1); and four equivalent Mg(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg6GaSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.163
_cell_length_b   6.028
_cell_length_c   6.096
_cell_angle_alpha   119.630
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   164.896
_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
  Ga  Ga0  1  0.500  0.667  0.334  1.0
  Mg  Mg1  1  1.000  0.833  0.172  1.0
  Mg  Mg2  1  1.000  0.340  0.172  1.0
  Mg  Mg3  1  0.000  0.333  0.666  1.0
  Mg  Mg4  1  0.500  0.669  0.826  1.0
  Mg  Mg5  1  0.500  0.157  0.826  1.0
  Mg  Mg6  1  0.500  0.167  0.334  1.0
  Si  Si7  1  0.000  0.835  0.669  1.0
[/CIF]
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The material described by Mg6GaSi crystallizes in the orthorhombic Amm2 space group. There are five 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 Ga(1), and two equivalent Si(1) atoms to form distorted MgMg8Ga2Si2 cuboctahedra that share corners with ten Mg(1,1)Mg8Ga2Si2 cuboctahedra; edges with two equivalent Mg(1)Mg8Ga2Si2 cuboctahedra; edges with four equivalent Mg(4)Mg10Ga2 cuboctahedra; edges with four equivalent Mg(3)Mg8Ga2Si2 cuboctahedra; faces with two equivalent Mg(4)Mg10Ga2 cuboctahedra; faces with four Mg(1,1)Mg8Ga2Si2 cuboctahedra; and faces with eight equivalent Mg(3)Mg8Ga2Si2 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 Ga(1), and two equivalent Si(1) atoms to form distorted MgMg8Ga2Si2 cuboctahedra that share corners with ten Mg(1,1)Mg8Ga2Si2 cuboctahedra; edges with two equivalent Mg(1)Mg8Ga2Si2 cuboctahedra; edges with four equivalent Mg(4)Mg10Ga2 cuboctahedra; edges with four equivalent Mg(3)Mg8Ga2Si2 cuboctahedra; faces with two equivalent Mg(4)Mg10Ga2 cuboctahedra; faces with four Mg(1,1)Mg8Ga2Si2 cuboctahedra; and faces with eight equivalent Mg(3)Mg8Ga2Si2 cuboctahedra. In the third Mg site, Mg(2) is bonded in a distorted linear geometry to two equivalent Mg(4); four Mg(1,1); four equivalent Mg(3); and two equivalent Si(1) atoms. In the fourth Mg site, Mg(3) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Ga(1), and two equivalent Si(1) atoms to form distorted MgMg8Ga2Si2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Ga2 cuboctahedra; corners with ten equivalent Mg(3)Mg8Ga2Si2 cuboctahedra; edges with two equivalent Mg(4)Mg10Ga2 cuboctahedra; edges with two equivalent Mg(3)Mg8Ga2Si2 cuboctahedra; edges with four equivalent Mg(1)Mg8Ga2Si2 cuboctahedra; faces with two equivalent Mg(4)Mg10Ga2 cuboctahedra; faces with four equivalent Mg(3)Mg8Ga2Si2 cuboctahedra; and faces with eight Mg(1,1)Mg8Ga2Si2 cuboctahedra. In the fifth Mg site, Mg(4) is bonded to two equivalent Mg(2); four Mg(1,1); four equivalent Mg(3); and two equivalent Ga(1) atoms to form distorted MgMg10Ga2 cuboctahedra that share corners with six equivalent Mg(4)Mg10Ga2 cuboctahedra; corners with eight equivalent Mg(3)Mg8Ga2Si2 cuboctahedra; edges with four equivalent Mg(3)Mg8Ga2Si2 cuboctahedra; edges with eight Mg(1,1)Mg8Ga2Si2 cuboctahedra; faces with two equivalent Mg(4)Mg10Ga2 cuboctahedra; faces with four Mg(1,1)Mg8Ga2Si2 cuboctahedra; and faces with four equivalent Mg(3)Mg8Ga2Si2 cuboctahedra. Ga(1) is bonded in a 10-coordinate geometry to two equivalent Mg(4); four Mg(1,1); and four equivalent Mg(3) atoms. Si(1) is bonded in a 10-coordinate geometry to two equivalent Mg(2); four Mg(1,1); and four equivalent Mg(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg6GaSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.163
_cell_length_b   6.028
_cell_length_c   6.096
_cell_angle_alpha   119.630
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   164.896
_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
  Ga  Ga0  1  0.500  0.667  0.334  1.0
  Mg  Mg1  1  1.000  0.833  0.172  1.0
  Mg  Mg2  1  1.000  0.340  0.172  1.0
  Mg  Mg3  1  0.000  0.333  0.666  1.0
  Mg  Mg4  1  0.500  0.669  0.826  1.0
  Mg  Mg5  1  0.500  0.157  0.826  1.0
  Mg  Mg6  1  0.500  0.167  0.334  1.0
  Si  Si7  1  0.000  0.835  0.669  1.0
[/CIF]
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