The structure described by Mg6NiSi crystallizes in the orthorhombic Amm2 space group. There are four 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 Ni(1), and two equivalent Si(1) atoms to form a mixture of distorted edge, face, and corner-sharing MgMg8Si2Ni2 cuboctahedra. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to two equivalent Mg(1), two equivalent Ni(1), and two equivalent Si(1) atoms. In the third Mg site, Mg(3) is bonded in a distorted water-like geometry to four equivalent Mg(1) and two equivalent Ni(1) atoms. In the fourth Mg site, Mg(4) is bonded in a distorted water-like geometry to four equivalent Mg(1) and two equivalent Si(1) atoms. Ni(1) is bonded in a 10-coordinate geometry to two equivalent Mg(3), four equivalent Mg(1), and four equivalent Mg(2) atoms. Si(1) is bonded in a 10-coordinate geometry to two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(2) atoms. is represented by the CIF card [CIF]
data_Mg6SiNi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.707
_cell_length_b   6.014
_cell_length_c   6.014
_cell_angle_alpha   118.393
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   149.775
_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  0.500  0.664  0.833  1.0
  Mg  Mg1  1  0.500  0.167  0.336  1.0
  Mg  Mg2  1  0.000  0.847  0.669  1.0
  Mg  Mg3  1  1.000  0.331  0.153  1.0
  Mg  Mg4  1  0.000  0.326  0.674  1.0
  Mg  Mg5  1  0.000  0.830  0.170  1.0
  Ni  Ni6  1  0.500  0.167  0.833  1.0
  Si  Si7  1  0.500  0.668  0.332  1.0
[/CIF]
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The structure described by Mg6NiSi crystallizes in the orthorhombic Amm2 space group. There are four 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 Ni(1), and two equivalent Si(1) atoms to form a mixture of distorted edge, face, and corner-sharing MgMg8Si2Ni2 cuboctahedra. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to two equivalent Mg(1), two equivalent Ni(1), and two equivalent Si(1) atoms. In the third Mg site, Mg(3) is bonded in a distorted water-like geometry to four equivalent Mg(1) and two equivalent Ni(1) atoms. In the fourth Mg site, Mg(4) is bonded in a distorted water-like geometry to four equivalent Mg(1) and two equivalent Si(1) atoms. Ni(1) is bonded in a 10-coordinate geometry to two equivalent Mg(3), four equivalent Mg(1), and four equivalent Mg(2) atoms. Si(1) is bonded in a 10-coordinate geometry to two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(2) atoms. is represented by the CIF card [CIF]
data_Mg6SiNi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.707
_cell_length_b   6.014
_cell_length_c   6.014
_cell_angle_alpha   118.393
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   149.775
_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  0.500  0.664  0.833  1.0
  Mg  Mg1  1  0.500  0.167  0.336  1.0
  Mg  Mg2  1  0.000  0.847  0.669  1.0
  Mg  Mg3  1  1.000  0.331  0.153  1.0
  Mg  Mg4  1  0.000  0.326  0.674  1.0
  Mg  Mg5  1  0.000  0.830  0.170  1.0
  Ni  Ni6  1  0.500  0.167  0.833  1.0
  Si  Si7  1  0.500  0.668  0.332  1.0
[/CIF]
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