The compound described by Mg3Y16Ni4Al crystallizes in the trigonal R3m space group. Mg(1) is bonded to two equivalent Mg(1), one Y(1), one Y(4), one Y(5), two equivalent Y(2), two equivalent Y(3), two equivalent Y(6), and one Al(1) atom to form distorted MgY9Mg2Al cuboctahedra that share  a cornercorner with one Al(1)Y9Mg3 cuboctahedra, corners with two equivalent Mg(1)Y9Mg2Al cuboctahedra,  a faceface with one Al(1)Y9Mg3 cuboctahedra, and faces with two equivalent Mg(1)Y9Mg2Al cuboctahedra. There are six inequivalent Y sites. In the first Y site, Y(1) is bonded in a 14-coordinate geometry to one Mg(1), one Y(5), one Y(6), two equivalent Y(1), two equivalent Y(2), two equivalent Y(3), two equivalent Y(4), two equivalent Ni(2), and one Al(1) atom. In the second Y site, Y(2) is bonded in a 14-coordinate geometry to two equivalent Mg(1), two equivalent Y(1), two equivalent Y(2), two equivalent Y(3), two equivalent Y(4), two equivalent Y(6), one Ni(1), and one Ni(2) atom. In the third Y site, Y(3) is bonded in a bent 150 degrees geometry to two equivalent Mg(1), two equivalent Y(1), two equivalent Y(2), one Ni(1), and one Ni(2) atom. In the fourth Y site, Y(4) is bonded in a distorted bent 150 degrees geometry to one Mg(1), two equivalent Y(1), two equivalent Y(2), two equivalent Ni(2), and one Al(1) atom. In the fifth Y site, Y(5) is bonded in a 3-coordinate geometry to three equivalent Mg(1), three equivalent Y(1), and three equivalent Ni(2) atoms. In the sixth Y site, Y(6) is bonded in a 3-coordinate geometry to two equivalent Mg(1), one Y(1), two equivalent Y(2), one Ni(1), two equivalent Ni(2), and one Al(1) atom. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 6-coordinate geometry to three equivalent Y(2), three equivalent Y(3), and three equivalent Y(6) atoms. In the second Ni site, Ni(2) is bonded in a 6-coordinate geometry to one Y(2), one Y(3), one Y(5), two equivalent Y(1), two equivalent Y(4), and two equivalent Y(6) atoms. Al(1) is bonded to three equivalent Mg(1), three equivalent Y(1), three equivalent Y(4), and three equivalent Y(6) atoms to form AlY9Mg3 cuboctahedra that share corners with three equivalent Mg(1)Y9Mg2Al cuboctahedra and faces with three equivalent Mg(1)Y9Mg2Al cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Y16Mg3AlNi4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.616
_cell_length_b   9.616
_cell_length_c   9.616
_cell_angle_alpha   60.508
_cell_angle_beta   60.508
_cell_angle_gamma   60.508
_symmetry_Int_Tables_number   1
_cell_volume   636.022
_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
  Y  Y0  1  0.435  0.069  0.435  1.0
  Y  Y1  1  0.069  0.435  0.435  1.0
  Y  Y2  1  0.435  0.435  0.069  1.0
  Y  Y3  1  0.065  0.435  0.065  1.0
  Y  Y4  1  0.435  0.065  0.065  1.0
  Y  Y5  1  0.065  0.065  0.435  1.0
  Y  Y6  1  0.814  0.187  0.814  1.0
  Y  Y7  1  0.187  0.814  0.814  1.0
  Y  Y8  1  0.814  0.814  0.187  1.0
  Y  Y9  1  0.190  0.810  0.190  1.0
  Y  Y10  1  0.810  0.190  0.190  1.0
  Y  Y11  1  0.190  0.190  0.810  1.0
  Y  Y12  1  0.653  0.653  0.653  1.0
  Y  Y13  1  0.651  0.651  0.045  1.0
  Y  Y14  1  0.045  0.651  0.651  1.0
  Y  Y15  1  0.651  0.045  0.651  1.0
  Mg  Mg16  1  0.420  0.420  0.735  1.0
  Mg  Mg17  1  0.735  0.420  0.420  1.0
  Mg  Mg18  1  0.420  0.735  0.420  1.0
  Al  Al19  1  0.418  0.418  0.418  1.0
  Ni  Ni20  1  0.857  0.857  0.857  1.0
  Ni  Ni21  1  0.858  0.858  0.426  1.0
  Ni  Ni22  1  0.426  0.858  0.858  1.0
  Ni  Ni23  1  0.858  0.426  0.858  1.0
[/CIF]
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The compound described by Mg3Y16Ni4Al crystallizes in the trigonal R3m space group. Mg(1) is bonded to two equivalent Mg(1), one Y(1), one Y(4), one Y(5), two equivalent Y(2), two equivalent Y(3), two equivalent Y(6), and one Al(1) atom to form distorted MgY9Mg2Al cuboctahedra that share  a cornercorner with one Al(1)Y9Mg3 cuboctahedra, corners with two equivalent Mg(1)Y9Mg2Al cuboctahedra,  a faceface with one Al(1)Y9Mg3 cuboctahedra, and faces with two equivalent Mg(1)Y9Mg2Al cuboctahedra. There are six inequivalent Y sites. In the first Y site, Y(1) is bonded in a 14-coordinate geometry to one Mg(1), one Y(5), one Y(6), two equivalent Y(1), two equivalent Y(2), two equivalent Y(3), two equivalent Y(4), two equivalent Ni(2), and one Al(1) atom. In the second Y site, Y(2) is bonded in a 14-coordinate geometry to two equivalent Mg(1), two equivalent Y(1), two equivalent Y(2), two equivalent Y(3), two equivalent Y(4), two equivalent Y(6), one Ni(1), and one Ni(2) atom. In the third Y site, Y(3) is bonded in a bent 150 degrees geometry to two equivalent Mg(1), two equivalent Y(1), two equivalent Y(2), one Ni(1), and one Ni(2) atom. In the fourth Y site, Y(4) is bonded in a distorted bent 150 degrees geometry to one Mg(1), two equivalent Y(1), two equivalent Y(2), two equivalent Ni(2), and one Al(1) atom. In the fifth Y site, Y(5) is bonded in a 3-coordinate geometry to three equivalent Mg(1), three equivalent Y(1), and three equivalent Ni(2) atoms. In the sixth Y site, Y(6) is bonded in a 3-coordinate geometry to two equivalent Mg(1), one Y(1), two equivalent Y(2), one Ni(1), two equivalent Ni(2), and one Al(1) atom. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 6-coordinate geometry to three equivalent Y(2), three equivalent Y(3), and three equivalent Y(6) atoms. In the second Ni site, Ni(2) is bonded in a 6-coordinate geometry to one Y(2), one Y(3), one Y(5), two equivalent Y(1), two equivalent Y(4), and two equivalent Y(6) atoms. Al(1) is bonded to three equivalent Mg(1), three equivalent Y(1), three equivalent Y(4), and three equivalent Y(6) atoms to form AlY9Mg3 cuboctahedra that share corners with three equivalent Mg(1)Y9Mg2Al cuboctahedra and faces with three equivalent Mg(1)Y9Mg2Al cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Y16Mg3AlNi4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.616
_cell_length_b   9.616
_cell_length_c   9.616
_cell_angle_alpha   60.508
_cell_angle_beta   60.508
_cell_angle_gamma   60.508
_symmetry_Int_Tables_number   1
_cell_volume   636.022
_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
  Y  Y0  1  0.435  0.069  0.435  1.0
  Y  Y1  1  0.069  0.435  0.435  1.0
  Y  Y2  1  0.435  0.435  0.069  1.0
  Y  Y3  1  0.065  0.435  0.065  1.0
  Y  Y4  1  0.435  0.065  0.065  1.0
  Y  Y5  1  0.065  0.065  0.435  1.0
  Y  Y6  1  0.814  0.187  0.814  1.0
  Y  Y7  1  0.187  0.814  0.814  1.0
  Y  Y8  1  0.814  0.814  0.187  1.0
  Y  Y9  1  0.190  0.810  0.190  1.0
  Y  Y10  1  0.810  0.190  0.190  1.0
  Y  Y11  1  0.190  0.190  0.810  1.0
  Y  Y12  1  0.653  0.653  0.653  1.0
  Y  Y13  1  0.651  0.651  0.045  1.0
  Y  Y14  1  0.045  0.651  0.651  1.0
  Y  Y15  1  0.651  0.045  0.651  1.0
  Mg  Mg16  1  0.420  0.420  0.735  1.0
  Mg  Mg17  1  0.735  0.420  0.420  1.0
  Mg  Mg18  1  0.420  0.735  0.420  1.0
  Al  Al19  1  0.418  0.418  0.418  1.0
  Ni  Ni20  1  0.857  0.857  0.857  1.0
  Ni  Ni21  1  0.858  0.858  0.426  1.0
  Ni  Ni22  1  0.426  0.858  0.858  1.0
  Ni  Ni23  1  0.858  0.426  0.858  1.0
[/CIF]
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