The structure described by MgY2 crystallizes in the hexagonal P-62m space group. Mg(1) is bonded to three equivalent Mg(1), three equivalent Y(2), and six equivalent Y(1) atoms to form distorted MgY9Mg3 cuboctahedra that share corners with nine equivalent Mg(1)Y9Mg3 cuboctahedra, corners with nine equivalent Y(2)Y6Mg6 cuboctahedra, edges with six equivalent Mg(1)Y9Mg3 cuboctahedra, edges with twelve equivalent Y(1)Y8Mg4 cuboctahedra, faces with three equivalent Y(2)Y6Mg6 cuboctahedra, faces with five equivalent Mg(1)Y9Mg3 cuboctahedra, and faces with twelve equivalent Y(1)Y8Mg4 cuboctahedra. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to four equivalent Mg(1), two equivalent Y(2), and six equivalent Y(1) atoms to form YY8Mg4 cuboctahedra that share corners with eighteen equivalent Y(1)Y8Mg4 cuboctahedra, edges with four equivalent Y(2)Y6Mg6 cuboctahedra, edges with six equivalent Y(1)Y8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Y9Mg3 cuboctahedra, faces with four equivalent Y(2)Y6Mg6 cuboctahedra, faces with eight equivalent Mg(1)Y9Mg3 cuboctahedra, and faces with eight equivalent Y(1)Y8Mg4 cuboctahedra. In the second Y site, Y(2) is bonded to six equivalent Mg(1) and six equivalent Y(1) atoms to form YY6Mg6 cuboctahedra that share corners with eighteen equivalent Mg(1)Y9Mg3 cuboctahedra, edges with six equivalent Y(2)Y6Mg6 cuboctahedra, edges with twelve equivalent Y(1)Y8Mg4 cuboctahedra, faces with two equivalent Y(2)Y6Mg6 cuboctahedra, faces with six equivalent Mg(1)Y9Mg3 cuboctahedra, and faces with twelve equivalent Y(1)Y8Mg4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Y2Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.043
_cell_length_b   6.043
_cell_length_c   5.637
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   178.291
_cell_formula_units_Z   2
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  0.656  0.000  0.000  1.0
  Y  Y1  1  0.344  0.344  0.000  1.0
  Y  Y2  1  0.000  0.656  0.000  1.0
  Y  Y3  1  0.000  0.000  0.500  1.0
  Mg  Mg4  1  0.667  0.333  0.500  1.0
  Mg  Mg5  1  0.333  0.667  0.500  1.0
[/CIF]
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The structure described by MgY2 crystallizes in the hexagonal P-62m space group. Mg(1) is bonded to three equivalent Mg(1), three equivalent Y(2), and six equivalent Y(1) atoms to form distorted MgY9Mg3 cuboctahedra that share corners with nine equivalent Mg(1)Y9Mg3 cuboctahedra, corners with nine equivalent Y(2)Y6Mg6 cuboctahedra, edges with six equivalent Mg(1)Y9Mg3 cuboctahedra, edges with twelve equivalent Y(1)Y8Mg4 cuboctahedra, faces with three equivalent Y(2)Y6Mg6 cuboctahedra, faces with five equivalent Mg(1)Y9Mg3 cuboctahedra, and faces with twelve equivalent Y(1)Y8Mg4 cuboctahedra. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to four equivalent Mg(1), two equivalent Y(2), and six equivalent Y(1) atoms to form YY8Mg4 cuboctahedra that share corners with eighteen equivalent Y(1)Y8Mg4 cuboctahedra, edges with four equivalent Y(2)Y6Mg6 cuboctahedra, edges with six equivalent Y(1)Y8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Y9Mg3 cuboctahedra, faces with four equivalent Y(2)Y6Mg6 cuboctahedra, faces with eight equivalent Mg(1)Y9Mg3 cuboctahedra, and faces with eight equivalent Y(1)Y8Mg4 cuboctahedra. In the second Y site, Y(2) is bonded to six equivalent Mg(1) and six equivalent Y(1) atoms to form YY6Mg6 cuboctahedra that share corners with eighteen equivalent Mg(1)Y9Mg3 cuboctahedra, edges with six equivalent Y(2)Y6Mg6 cuboctahedra, edges with twelve equivalent Y(1)Y8Mg4 cuboctahedra, faces with two equivalent Y(2)Y6Mg6 cuboctahedra, faces with six equivalent Mg(1)Y9Mg3 cuboctahedra, and faces with twelve equivalent Y(1)Y8Mg4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Y2Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.043
_cell_length_b   6.043
_cell_length_c   5.637
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   178.291
_cell_formula_units_Z   2
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  0.656  0.000  0.000  1.0
  Y  Y1  1  0.344  0.344  0.000  1.0
  Y  Y2  1  0.000  0.656  0.000  1.0
  Y  Y3  1  0.000  0.000  0.500  1.0
  Mg  Mg4  1  0.667  0.333  0.500  1.0
  Mg  Mg5  1  0.333  0.667  0.500  1.0
[/CIF]
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