The material described by MoNiSi is Frank-Kasper $\mu$ Phase-derived structured and crystallizes in the orthorhombic Amm2 space group. There are six inequivalent Mo sites. In the first Mo site, Mo(1) is bonded in a 16-coordinate geometry to one Mo(1), three equivalent Mo(2), one Ni(1), two equivalent Ni(2), two equivalent Ni(3), three equivalent Si(2), and four equivalent Si(1) atoms. In the second Mo site, Mo(2) is bonded in a 16-coordinate geometry to one Mo(2); three Mo(1,1); one Ni(3); two equivalent Ni(1); four equivalent Ni(2); two equivalent Si(1); and three equivalent Si(2) atoms. In the third Mo site, Mo(2) is bonded in a 16-coordinate geometry to one Mo(2); three Mo(1,1); one Ni(3); two equivalent Ni(1); four equivalent Ni(2); two equivalent Si(1); and three equivalent Si(2) atoms. In the fourth Mo site, Mo(1) is bonded in a 16-coordinate geometry to one Mo(1); three Mo(2,2); one Ni(1); two equivalent Ni(2); two equivalent Ni(3); three equivalent Si(2); and four equivalent Si(1) atoms. In the fifth Mo site, Mo(2) is bonded in a 16-coordinate geometry to one Mo(2); three Mo(1,1); one Ni(3); two equivalent Ni(1); four equivalent Ni(2); two equivalent Si(1); and three equivalent Si(2) atoms. In the sixth Mo site, Mo(1) is bonded in a 16-coordinate geometry to one Mo(1); three Mo(2,2); one Ni(1); two equivalent Ni(2); two equivalent Ni(3); three equivalent Si(2); and four equivalent Si(1) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two Mo(1,1); four Mo(2,2); four equivalent Ni(2); and two equivalent Si(2) atoms to form NiSi2Ni4Mo6 cuboctahedra that share corners with two equivalent Ni(3)Si6Mo6 cuboctahedra, corners with four equivalent Ni(1)Si2Ni4Mo6 cuboctahedra, corners with four equivalent Si(2)Si2Ni4Mo6 cuboctahedra, corners with eight equivalent Si(1)Si4Ni2Mo6 cuboctahedra, edges with two equivalent Ni(1)Si2Ni4Mo6 cuboctahedra, edges with four equivalent Ni(3)Si6Mo6 cuboctahedra, faces with four equivalent Si(1)Si4Ni2Mo6 cuboctahedra, faces with six equivalent Si(2)Si2Ni4Mo6 cuboctahedra, and faces with eight equivalent Ni(2)Si2Ni4Mo6 cuboctahedra. In the second Ni site, Ni(2) is bonded to two Mo(1,1); four Mo(2,2,2); two equivalent Ni(1); two equivalent Ni(2); and two equivalent Si(2) atoms to form distorted NiSi2Ni4Mo6 cuboctahedra that share corners with four equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, corners with four equivalent Ni(3)Si6Mo6 cuboctahedra, corners with four equivalent Si(2)Si2Ni4Mo6 cuboctahedra, corners with six equivalent Si(1)Si4Ni2Mo6 cuboctahedra, edges with two equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, edges with four equivalent Si(1)Si4Ni2Mo6 cuboctahedra, faces with two equivalent Ni(3)Si6Mo6 cuboctahedra, faces with two equivalent Si(1)Si4Ni2Mo6 cuboctahedra, faces with four equivalent Ni(1)Si2Ni4Mo6 cuboctahedra, faces with four equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, and faces with six equivalent Si(2)Si2Ni4Mo6 cuboctahedra. In the third Ni site, Ni(3) is bonded to two Mo(2,2); four Mo(1,1); two equivalent Si(2); and four equivalent Si(1) atoms to form NiSi6Mo6 cuboctahedra that share corners with two equivalent Ni(1)Si2Ni4Mo6 cuboctahedra, corners with four equivalent Ni(3)Si6Mo6 cuboctahedra, corners with four equivalent Si(2)Si2Ni4Mo6 cuboctahedra, corners with eight equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, edges with two equivalent Ni(3)Si6Mo6 cuboctahedra, edges with four equivalent Ni(1)Si2Ni4Mo6 cuboctahedra, faces with four equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, faces with six equivalent Si(2)Si2Ni4Mo6 cuboctahedra, and faces with eight equivalent Si(1)Si4Ni2Mo6 cuboctahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to two Mo(2,2); four Mo(1,1,1); two equivalent Ni(3); two equivalent Si(1); and two equivalent Si(2) atoms to form SiSi4Ni2Mo6 cuboctahedra that share corners with four equivalent Ni(1)Si2Ni4Mo6 cuboctahedra, corners with four equivalent Si(2)Si2Ni4Mo6 cuboctahedra, corners with four equivalent Si(1)Si4Ni2Mo6 cuboctahedra, corners with six equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, edges with two equivalent Si(1)Si4Ni2Mo6 cuboctahedra, edges with four equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, faces with two equivalent Ni(1)Si2Ni4Mo6 cuboctahedra, faces with two equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, faces with four equivalent Ni(3)Si6Mo6 cuboctahedra, faces with four equivalent Si(1)Si4Ni2Mo6 cuboctahedra, and faces with six equivalent Si(2)Si2Ni4Mo6 cuboctahedra. In the second Si site, Si(2) is bonded to three Mo(1,1); three Mo(2,2); one Ni(1); one Ni(3); two equivalent Ni(2); and two equivalent Si(1) atoms to form distorted SiSi2Ni4Mo6 cuboctahedra that share corners with two equivalent Ni(1)Si2Ni4Mo6 cuboctahedra, corners with two equivalent Ni(3)Si6Mo6 cuboctahedra, corners with four equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, corners with four equivalent Si(1)Si4Ni2Mo6 cuboctahedra, edges with six equivalent Si(2)Si2Ni4Mo6 cuboctahedra, faces with two equivalent Si(2)Si2Ni4Mo6 cuboctahedra, faces with three equivalent Ni(1)Si2Ni4Mo6 cuboctahedra, faces with three equivalent Ni(3)Si6Mo6 cuboctahedra, faces with six equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, and faces with six equivalent Si(1)Si4Ni2Mo6 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_SiNiMo
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.719
_cell_length_b   4.719
_cell_length_c   7.710
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   117.898
_symmetry_Int_Tables_number   1
_cell_volume   151.723
_cell_formula_units_Z   4
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
  Si  Si0  1  0.161  0.349  0.500  1.0
  Si  Si1  1  0.651  0.839  0.500  1.0
  Si  Si2  1  0.009  0.991  0.231  1.0
  Si  Si3  1  0.009  0.991  0.769  1.0
  Ni  Ni4  1  0.831  0.169  0.000  1.0
  Ni  Ni5  1  0.829  0.654  0.000  1.0
  Ni  Ni6  1  0.346  0.171  0.000  1.0
  Ni  Ni7  1  0.153  0.847  0.500  1.0
  Mo  Mo8  1  0.665  0.335  0.687  1.0
  Mo  Mo9  1  0.341  0.659  0.807  1.0
  Mo  Mo10  1  0.341  0.659  0.193  1.0
  Mo  Mo11  1  0.665  0.335  0.313  1.0
[/CIF]
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The material described by MoNiSi is Frank-Kasper $\mu$ Phase-derived structured and crystallizes in the orthorhombic Amm2 space group. There are six inequivalent Mo sites. In the first Mo site, Mo(1) is bonded in a 16-coordinate geometry to one Mo(1), three equivalent Mo(2), one Ni(1), two equivalent Ni(2), two equivalent Ni(3), three equivalent Si(2), and four equivalent Si(1) atoms. In the second Mo site, Mo(2) is bonded in a 16-coordinate geometry to one Mo(2); three Mo(1,1); one Ni(3); two equivalent Ni(1); four equivalent Ni(2); two equivalent Si(1); and three equivalent Si(2) atoms. In the third Mo site, Mo(2) is bonded in a 16-coordinate geometry to one Mo(2); three Mo(1,1); one Ni(3); two equivalent Ni(1); four equivalent Ni(2); two equivalent Si(1); and three equivalent Si(2) atoms. In the fourth Mo site, Mo(1) is bonded in a 16-coordinate geometry to one Mo(1); three Mo(2,2); one Ni(1); two equivalent Ni(2); two equivalent Ni(3); three equivalent Si(2); and four equivalent Si(1) atoms. In the fifth Mo site, Mo(2) is bonded in a 16-coordinate geometry to one Mo(2); three Mo(1,1); one Ni(3); two equivalent Ni(1); four equivalent Ni(2); two equivalent Si(1); and three equivalent Si(2) atoms. In the sixth Mo site, Mo(1) is bonded in a 16-coordinate geometry to one Mo(1); three Mo(2,2); one Ni(1); two equivalent Ni(2); two equivalent Ni(3); three equivalent Si(2); and four equivalent Si(1) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two Mo(1,1); four Mo(2,2); four equivalent Ni(2); and two equivalent Si(2) atoms to form NiSi2Ni4Mo6 cuboctahedra that share corners with two equivalent Ni(3)Si6Mo6 cuboctahedra, corners with four equivalent Ni(1)Si2Ni4Mo6 cuboctahedra, corners with four equivalent Si(2)Si2Ni4Mo6 cuboctahedra, corners with eight equivalent Si(1)Si4Ni2Mo6 cuboctahedra, edges with two equivalent Ni(1)Si2Ni4Mo6 cuboctahedra, edges with four equivalent Ni(3)Si6Mo6 cuboctahedra, faces with four equivalent Si(1)Si4Ni2Mo6 cuboctahedra, faces with six equivalent Si(2)Si2Ni4Mo6 cuboctahedra, and faces with eight equivalent Ni(2)Si2Ni4Mo6 cuboctahedra. In the second Ni site, Ni(2) is bonded to two Mo(1,1); four Mo(2,2,2); two equivalent Ni(1); two equivalent Ni(2); and two equivalent Si(2) atoms to form distorted NiSi2Ni4Mo6 cuboctahedra that share corners with four equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, corners with four equivalent Ni(3)Si6Mo6 cuboctahedra, corners with four equivalent Si(2)Si2Ni4Mo6 cuboctahedra, corners with six equivalent Si(1)Si4Ni2Mo6 cuboctahedra, edges with two equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, edges with four equivalent Si(1)Si4Ni2Mo6 cuboctahedra, faces with two equivalent Ni(3)Si6Mo6 cuboctahedra, faces with two equivalent Si(1)Si4Ni2Mo6 cuboctahedra, faces with four equivalent Ni(1)Si2Ni4Mo6 cuboctahedra, faces with four equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, and faces with six equivalent Si(2)Si2Ni4Mo6 cuboctahedra. In the third Ni site, Ni(3) is bonded to two Mo(2,2); four Mo(1,1); two equivalent Si(2); and four equivalent Si(1) atoms to form NiSi6Mo6 cuboctahedra that share corners with two equivalent Ni(1)Si2Ni4Mo6 cuboctahedra, corners with four equivalent Ni(3)Si6Mo6 cuboctahedra, corners with four equivalent Si(2)Si2Ni4Mo6 cuboctahedra, corners with eight equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, edges with two equivalent Ni(3)Si6Mo6 cuboctahedra, edges with four equivalent Ni(1)Si2Ni4Mo6 cuboctahedra, faces with four equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, faces with six equivalent Si(2)Si2Ni4Mo6 cuboctahedra, and faces with eight equivalent Si(1)Si4Ni2Mo6 cuboctahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to two Mo(2,2); four Mo(1,1,1); two equivalent Ni(3); two equivalent Si(1); and two equivalent Si(2) atoms to form SiSi4Ni2Mo6 cuboctahedra that share corners with four equivalent Ni(1)Si2Ni4Mo6 cuboctahedra, corners with four equivalent Si(2)Si2Ni4Mo6 cuboctahedra, corners with four equivalent Si(1)Si4Ni2Mo6 cuboctahedra, corners with six equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, edges with two equivalent Si(1)Si4Ni2Mo6 cuboctahedra, edges with four equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, faces with two equivalent Ni(1)Si2Ni4Mo6 cuboctahedra, faces with two equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, faces with four equivalent Ni(3)Si6Mo6 cuboctahedra, faces with four equivalent Si(1)Si4Ni2Mo6 cuboctahedra, and faces with six equivalent Si(2)Si2Ni4Mo6 cuboctahedra. In the second Si site, Si(2) is bonded to three Mo(1,1); three Mo(2,2); one Ni(1); one Ni(3); two equivalent Ni(2); and two equivalent Si(1) atoms to form distorted SiSi2Ni4Mo6 cuboctahedra that share corners with two equivalent Ni(1)Si2Ni4Mo6 cuboctahedra, corners with two equivalent Ni(3)Si6Mo6 cuboctahedra, corners with four equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, corners with four equivalent Si(1)Si4Ni2Mo6 cuboctahedra, edges with six equivalent Si(2)Si2Ni4Mo6 cuboctahedra, faces with two equivalent Si(2)Si2Ni4Mo6 cuboctahedra, faces with three equivalent Ni(1)Si2Ni4Mo6 cuboctahedra, faces with three equivalent Ni(3)Si6Mo6 cuboctahedra, faces with six equivalent Ni(2)Si2Ni4Mo6 cuboctahedra, and faces with six equivalent Si(1)Si4Ni2Mo6 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_SiNiMo
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.719
_cell_length_b   4.719
_cell_length_c   7.710
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   117.898
_symmetry_Int_Tables_number   1
_cell_volume   151.723
_cell_formula_units_Z   4
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
  Si  Si0  1  0.161  0.349  0.500  1.0
  Si  Si1  1  0.651  0.839  0.500  1.0
  Si  Si2  1  0.009  0.991  0.231  1.0
  Si  Si3  1  0.009  0.991  0.769  1.0
  Ni  Ni4  1  0.831  0.169  0.000  1.0
  Ni  Ni5  1  0.829  0.654  0.000  1.0
  Ni  Ni6  1  0.346  0.171  0.000  1.0
  Ni  Ni7  1  0.153  0.847  0.500  1.0
  Mo  Mo8  1  0.665  0.335  0.687  1.0
  Mo  Mo9  1  0.341  0.659  0.807  1.0
  Mo  Mo10  1  0.341  0.659  0.193  1.0
  Mo  Mo11  1  0.665  0.335  0.313  1.0
[/CIF]
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