The material structure described by MgY crystallizes in the monoclinic Cm space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent Mg(1), two equivalent Mg(3), three equivalent Mg(2), one Y(2), two equivalent Y(1), and two equivalent Y(3) atoms. In the second Mg site, Mg(2) is bonded in a 12-coordinate geometry to two equivalent Mg(2), two equivalent Mg(3), three equivalent Mg(1), one Y(3), two equivalent Y(1), and two equivalent Y(2) atoms. In the third Mg site, Mg(3) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), one Y(1), two equivalent Y(3), and three equivalent Y(2) atoms to form distorted MgY6Mg6 cuboctahedra that share corners with six equivalent Mg(3)Y6Mg6 cuboctahedra, corners with six equivalent Y(3)Y7Mg5 cuboctahedra, edges with two equivalent Y(2)Y6Mg6 cuboctahedra, edges with three equivalent Y(3)Y7Mg5 cuboctahedra, edges with four equivalent Y(1)Y7Mg5 cuboctahedra, faces with two equivalent Mg(3)Y6Mg6 cuboctahedra, faces with three equivalent Y(3)Y7Mg5 cuboctahedra, faces with four equivalent Y(1)Y7Mg5 cuboctahedra, and faces with five equivalent Y(2)Y6Mg6 cuboctahedra. There are three inequivalent Y sites. In the first Y site, Y(1) is bonded to one Mg(3), two equivalent Mg(1), two equivalent Mg(2), two equivalent Y(1), two equivalent Y(2), and three equivalent Y(3) atoms to form YY7Mg5 cuboctahedra that share corners with six equivalent Y(2)Y6Mg6 cuboctahedra, corners with six equivalent Y(1)Y7Mg5 cuboctahedra, edges with two equivalent Y(3)Y7Mg5 cuboctahedra, edges with three equivalent Y(2)Y6Mg6 cuboctahedra, edges with four equivalent Mg(3)Y6Mg6 cuboctahedra, faces with two equivalent Y(1)Y7Mg5 cuboctahedra, faces with three equivalent Y(2)Y6Mg6 cuboctahedra, faces with four equivalent Mg(3)Y6Mg6 cuboctahedra, and faces with five equivalent Y(3)Y7Mg5 cuboctahedra. In the second Y site, Y(2) is bonded to one Mg(1), two equivalent Mg(2), three equivalent Mg(3), two equivalent Y(1), two equivalent Y(2), and two equivalent Y(3) atoms to form distorted YY6Mg6 cuboctahedra that share corners with six equivalent Y(2)Y6Mg6 cuboctahedra, corners with six equivalent Y(1)Y7Mg5 cuboctahedra, edges with two equivalent Mg(3)Y6Mg6 cuboctahedra, edges with three equivalent Y(1)Y7Mg5 cuboctahedra, edges with six equivalent Y(3)Y7Mg5 cuboctahedra, faces with two equivalent Y(2)Y6Mg6 cuboctahedra, faces with three equivalent Y(1)Y7Mg5 cuboctahedra, faces with three equivalent Y(3)Y7Mg5 cuboctahedra, and faces with five equivalent Mg(3)Y6Mg6 cuboctahedra. In the third Y site, Y(3) is bonded to one Mg(2), two equivalent Mg(1), two equivalent Mg(3), two equivalent Y(2), two equivalent Y(3), and three equivalent Y(1) atoms to form YY7Mg5 cuboctahedra that share corners with six equivalent Mg(3)Y6Mg6 cuboctahedra, corners with six equivalent Y(3)Y7Mg5 cuboctahedra, edges with two equivalent Y(1)Y7Mg5 cuboctahedra, edges with three equivalent Mg(3)Y6Mg6 cuboctahedra, edges with six equivalent Y(2)Y6Mg6 cuboctahedra, faces with two equivalent Y(3)Y7Mg5 cuboctahedra, faces with three equivalent Mg(3)Y6Mg6 cuboctahedra, faces with three equivalent Y(2)Y6Mg6 cuboctahedra, and faces with five equivalent Y(1)Y7Mg5 cuboctahedra. is represented by the CIF card [CIF]
data_YMg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.688
_cell_length_b   6.688
_cell_length_c   7.843
_cell_angle_alpha   75.481
_cell_angle_beta   75.481
_cell_angle_gamma   30.320
_symmetry_Int_Tables_number   1
_cell_volume   171.036
_cell_formula_units_Z   3
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  0.998  0.998  0.009  1.0
  Y  Y1  1  0.668  0.668  0.658  1.0
  Y  Y2  1  0.279  0.279  0.945  1.0
  Mg  Mg3  1  0.610  0.610  0.281  1.0
  Mg  Mg4  1  0.336  0.336  0.336  1.0
  Mg  Mg5  1  0.942  0.942  0.605  1.0
[/CIF]
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The material structure described by MgY crystallizes in the monoclinic Cm space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent Mg(1), two equivalent Mg(3), three equivalent Mg(2), one Y(2), two equivalent Y(1), and two equivalent Y(3) atoms. In the second Mg site, Mg(2) is bonded in a 12-coordinate geometry to two equivalent Mg(2), two equivalent Mg(3), three equivalent Mg(1), one Y(3), two equivalent Y(1), and two equivalent Y(2) atoms. In the third Mg site, Mg(3) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), one Y(1), two equivalent Y(3), and three equivalent Y(2) atoms to form distorted MgY6Mg6 cuboctahedra that share corners with six equivalent Mg(3)Y6Mg6 cuboctahedra, corners with six equivalent Y(3)Y7Mg5 cuboctahedra, edges with two equivalent Y(2)Y6Mg6 cuboctahedra, edges with three equivalent Y(3)Y7Mg5 cuboctahedra, edges with four equivalent Y(1)Y7Mg5 cuboctahedra, faces with two equivalent Mg(3)Y6Mg6 cuboctahedra, faces with three equivalent Y(3)Y7Mg5 cuboctahedra, faces with four equivalent Y(1)Y7Mg5 cuboctahedra, and faces with five equivalent Y(2)Y6Mg6 cuboctahedra. There are three inequivalent Y sites. In the first Y site, Y(1) is bonded to one Mg(3), two equivalent Mg(1), two equivalent Mg(2), two equivalent Y(1), two equivalent Y(2), and three equivalent Y(3) atoms to form YY7Mg5 cuboctahedra that share corners with six equivalent Y(2)Y6Mg6 cuboctahedra, corners with six equivalent Y(1)Y7Mg5 cuboctahedra, edges with two equivalent Y(3)Y7Mg5 cuboctahedra, edges with three equivalent Y(2)Y6Mg6 cuboctahedra, edges with four equivalent Mg(3)Y6Mg6 cuboctahedra, faces with two equivalent Y(1)Y7Mg5 cuboctahedra, faces with three equivalent Y(2)Y6Mg6 cuboctahedra, faces with four equivalent Mg(3)Y6Mg6 cuboctahedra, and faces with five equivalent Y(3)Y7Mg5 cuboctahedra. In the second Y site, Y(2) is bonded to one Mg(1), two equivalent Mg(2), three equivalent Mg(3), two equivalent Y(1), two equivalent Y(2), and two equivalent Y(3) atoms to form distorted YY6Mg6 cuboctahedra that share corners with six equivalent Y(2)Y6Mg6 cuboctahedra, corners with six equivalent Y(1)Y7Mg5 cuboctahedra, edges with two equivalent Mg(3)Y6Mg6 cuboctahedra, edges with three equivalent Y(1)Y7Mg5 cuboctahedra, edges with six equivalent Y(3)Y7Mg5 cuboctahedra, faces with two equivalent Y(2)Y6Mg6 cuboctahedra, faces with three equivalent Y(1)Y7Mg5 cuboctahedra, faces with three equivalent Y(3)Y7Mg5 cuboctahedra, and faces with five equivalent Mg(3)Y6Mg6 cuboctahedra. In the third Y site, Y(3) is bonded to one Mg(2), two equivalent Mg(1), two equivalent Mg(3), two equivalent Y(2), two equivalent Y(3), and three equivalent Y(1) atoms to form YY7Mg5 cuboctahedra that share corners with six equivalent Mg(3)Y6Mg6 cuboctahedra, corners with six equivalent Y(3)Y7Mg5 cuboctahedra, edges with two equivalent Y(1)Y7Mg5 cuboctahedra, edges with three equivalent Mg(3)Y6Mg6 cuboctahedra, edges with six equivalent Y(2)Y6Mg6 cuboctahedra, faces with two equivalent Y(3)Y7Mg5 cuboctahedra, faces with three equivalent Mg(3)Y6Mg6 cuboctahedra, faces with three equivalent Y(2)Y6Mg6 cuboctahedra, and faces with five equivalent Y(1)Y7Mg5 cuboctahedra. is represented by the CIF card [CIF]
data_YMg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.688
_cell_length_b   6.688
_cell_length_c   7.843
_cell_angle_alpha   75.481
_cell_angle_beta   75.481
_cell_angle_gamma   30.320
_symmetry_Int_Tables_number   1
_cell_volume   171.036
_cell_formula_units_Z   3
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  0.998  0.998  0.009  1.0
  Y  Y1  1  0.668  0.668  0.658  1.0
  Y  Y2  1  0.279  0.279  0.945  1.0
  Mg  Mg3  1  0.610  0.610  0.281  1.0
  Mg  Mg4  1  0.336  0.336  0.336  1.0
  Mg  Mg5  1  0.942  0.942  0.605  1.0
[/CIF]
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