The crystal structure described by Mg14NiSi crystallizes in the orthorhombic Amm2 space group. There are seven inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(2), two equivalent Mg(6), four equivalent Mg(4), and four equivalent Mg(5) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(1)Mg12 cuboctahedra, edges with two equivalent Mg(2)Mg12 cuboctahedra, edges with four equivalent Mg(6)Mg11Ni cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Mg(6)Mg11Ni cuboctahedra, faces with two equivalent Mg(2)Mg12 cuboctahedra, faces with four equivalent Mg(4)Mg12 cuboctahedra, and faces with six equivalent Mg(7)Mg11Si cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(7), four equivalent Mg(4), and four equivalent Mg(5) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(2)Mg12 cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with four equivalent Mg(7)Mg11Si cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Mg(7)Mg11Si cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with four equivalent Mg(4)Mg12 cuboctahedra, and faces with six equivalent Mg(6)Mg11Ni cuboctahedra. In the third Mg site, Mg(3) is bonded in a 2-coordinate geometry to two equivalent Mg(6), two equivalent Mg(7), one Ni(1), and one Si(1) atom. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), two equivalent Mg(6), and two equivalent Mg(7) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(4)Mg12 cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with two equivalent Mg(2)Mg12 cuboctahedra, edges with two equivalent Mg(4)Mg12 cuboctahedra, edges with four equivalent Mg(6)Mg11Ni cuboctahedra, edges with four equivalent Mg(7)Mg11Si cuboctahedra, faces with two equivalent Mg(6)Mg11Ni cuboctahedra, faces with two equivalent Mg(7)Mg11Si cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with two equivalent Mg(2)Mg12 cuboctahedra, and faces with two equivalent Mg(4)Mg12 cuboctahedra. In the fifth Mg site, Mg(5) is bonded in a 2-coordinate geometry to one Mg(1), one Mg(2), one Mg(4), two equivalent Mg(6), two equivalent Mg(7), one Ni(1), and one Si(1) atom. In the sixth Mg site, Mg(6) is bonded to one Mg(1), two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(7), four equivalent Mg(5), and one Ni(1) atom to form distorted MgMg11Ni cuboctahedra that share corners with four equivalent Mg(7)Mg11Si cuboctahedra, corners with six equivalent Mg(6)Mg11Ni cuboctahedra, edges with two equivalent Mg(7)Mg11Si cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra,  a faceface with one Mg(1)Mg12 cuboctahedra, faces with two equivalent Mg(6)Mg11Ni cuboctahedra, faces with two equivalent Mg(7)Mg11Si cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, and faces with three equivalent Mg(2)Mg12 cuboctahedra. In the seventh Mg site, Mg(7) is bonded to one Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(6), four equivalent Mg(5), and one Si(1) atom to form distorted MgMg11Si cuboctahedra that share corners with four equivalent Mg(6)Mg11Ni cuboctahedra, corners with six equivalent Mg(7)Mg11Si cuboctahedra, edges with two equivalent Mg(6)Mg11Ni cuboctahedra, edges with two equivalent Mg(2)Mg12 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra,  a faceface with one Mg(2)Mg12 cuboctahedra, faces with two equivalent Mg(6)Mg11Ni cuboctahedra, faces with two equivalent Mg(7)Mg11Si cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, and faces with three equivalent Mg(1)Mg12 cuboctahedra. Ni(1) is bonded in a 8-coordinate geometry to two equivalent Mg(3), two equivalent Mg(6), and four equivalent Mg(5) atoms. Si(1) is bonded in a 8-coordinate geometry to two equivalent Mg(3), two equivalent Mg(7), and four equivalent Mg(5) atoms. is represented by the CIF card [CIF]
data_Mg14SiNi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.187
_cell_length_b   6.252
_cell_length_c   10.037
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.347
_symmetry_Int_Tables_number   1
_cell_volume   335.061
_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  0.172  0.336  0.625  1.0
  Mg  Mg1  1  0.171  0.836  0.625  1.0
  Mg  Mg2  1  0.714  0.355  0.125  1.0
  Mg  Mg3  1  0.662  0.330  0.625  1.0
  Mg  Mg4  1  0.714  0.859  0.125  1.0
  Mg  Mg5  1  0.662  0.832  0.625  1.0
  Mg  Mg6  1  0.318  0.163  0.342  1.0
  Mg  Mg7  1  0.318  0.163  0.908  1.0
  Mg  Mg8  1  0.318  0.655  0.342  1.0
  Mg  Mg9  1  0.318  0.655  0.908  1.0
  Mg  Mg10  1  0.835  0.168  0.371  1.0
  Mg  Mg11  1  0.835  0.168  0.879  1.0
  Mg  Mg12  1  0.830  0.665  0.376  1.0
  Mg  Mg13  1  0.830  0.665  0.874  1.0
  Si  Si14  1  0.155  0.827  0.125  1.0
  Ni  Ni15  1  0.147  0.323  0.125  1.0
[/CIF]
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The crystal structure described by Mg14NiSi crystallizes in the orthorhombic Amm2 space group. There are seven inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(2), two equivalent Mg(6), four equivalent Mg(4), and four equivalent Mg(5) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(1)Mg12 cuboctahedra, edges with two equivalent Mg(2)Mg12 cuboctahedra, edges with four equivalent Mg(6)Mg11Ni cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Mg(6)Mg11Ni cuboctahedra, faces with two equivalent Mg(2)Mg12 cuboctahedra, faces with four equivalent Mg(4)Mg12 cuboctahedra, and faces with six equivalent Mg(7)Mg11Si cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(7), four equivalent Mg(4), and four equivalent Mg(5) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(2)Mg12 cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with four equivalent Mg(7)Mg11Si cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Mg(7)Mg11Si cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with four equivalent Mg(4)Mg12 cuboctahedra, and faces with six equivalent Mg(6)Mg11Ni cuboctahedra. In the third Mg site, Mg(3) is bonded in a 2-coordinate geometry to two equivalent Mg(6), two equivalent Mg(7), one Ni(1), and one Si(1) atom. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), two equivalent Mg(6), and two equivalent Mg(7) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(4)Mg12 cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with two equivalent Mg(2)Mg12 cuboctahedra, edges with two equivalent Mg(4)Mg12 cuboctahedra, edges with four equivalent Mg(6)Mg11Ni cuboctahedra, edges with four equivalent Mg(7)Mg11Si cuboctahedra, faces with two equivalent Mg(6)Mg11Ni cuboctahedra, faces with two equivalent Mg(7)Mg11Si cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with two equivalent Mg(2)Mg12 cuboctahedra, and faces with two equivalent Mg(4)Mg12 cuboctahedra. In the fifth Mg site, Mg(5) is bonded in a 2-coordinate geometry to one Mg(1), one Mg(2), one Mg(4), two equivalent Mg(6), two equivalent Mg(7), one Ni(1), and one Si(1) atom. In the sixth Mg site, Mg(6) is bonded to one Mg(1), two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(7), four equivalent Mg(5), and one Ni(1) atom to form distorted MgMg11Ni cuboctahedra that share corners with four equivalent Mg(7)Mg11Si cuboctahedra, corners with six equivalent Mg(6)Mg11Ni cuboctahedra, edges with two equivalent Mg(7)Mg11Si cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra,  a faceface with one Mg(1)Mg12 cuboctahedra, faces with two equivalent Mg(6)Mg11Ni cuboctahedra, faces with two equivalent Mg(7)Mg11Si cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, and faces with three equivalent Mg(2)Mg12 cuboctahedra. In the seventh Mg site, Mg(7) is bonded to one Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(6), four equivalent Mg(5), and one Si(1) atom to form distorted MgMg11Si cuboctahedra that share corners with four equivalent Mg(6)Mg11Ni cuboctahedra, corners with six equivalent Mg(7)Mg11Si cuboctahedra, edges with two equivalent Mg(6)Mg11Ni cuboctahedra, edges with two equivalent Mg(2)Mg12 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra,  a faceface with one Mg(2)Mg12 cuboctahedra, faces with two equivalent Mg(6)Mg11Ni cuboctahedra, faces with two equivalent Mg(7)Mg11Si cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, and faces with three equivalent Mg(1)Mg12 cuboctahedra. Ni(1) is bonded in a 8-coordinate geometry to two equivalent Mg(3), two equivalent Mg(6), and four equivalent Mg(5) atoms. Si(1) is bonded in a 8-coordinate geometry to two equivalent Mg(3), two equivalent Mg(7), and four equivalent Mg(5) atoms. is represented by the CIF card [CIF]
data_Mg14SiNi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.187
_cell_length_b   6.252
_cell_length_c   10.037
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.347
_symmetry_Int_Tables_number   1
_cell_volume   335.061
_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  0.172  0.336  0.625  1.0
  Mg  Mg1  1  0.171  0.836  0.625  1.0
  Mg  Mg2  1  0.714  0.355  0.125  1.0
  Mg  Mg3  1  0.662  0.330  0.625  1.0
  Mg  Mg4  1  0.714  0.859  0.125  1.0
  Mg  Mg5  1  0.662  0.832  0.625  1.0
  Mg  Mg6  1  0.318  0.163  0.342  1.0
  Mg  Mg7  1  0.318  0.163  0.908  1.0
  Mg  Mg8  1  0.318  0.655  0.342  1.0
  Mg  Mg9  1  0.318  0.655  0.908  1.0
  Mg  Mg10  1  0.835  0.168  0.371  1.0
  Mg  Mg11  1  0.835  0.168  0.879  1.0
  Mg  Mg12  1  0.830  0.665  0.376  1.0
  Mg  Mg13  1  0.830  0.665  0.874  1.0
  Si  Si14  1  0.155  0.827  0.125  1.0
  Ni  Ni15  1  0.147  0.323  0.125  1.0
[/CIF]
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