The compound described by Mg2Y is beta-derived structured and crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to four equivalent Mg(1), six equivalent Mg(2), and two equivalent Y(1) atoms to form distorted MgY2Mg10 cuboctahedra that share corners with six equivalent Mg(1)Y2Mg10 cuboctahedra, corners with six equivalent Mg(2)Y4Mg8 cuboctahedra, corners with six equivalent Y(1)Y6Mg6 cuboctahedra, edges with seven equivalent Mg(2)Y4Mg8 cuboctahedra, edges with eleven equivalent Y(1)Y6Mg6 cuboctahedra, faces with four equivalent Y(1)Y6Mg6 cuboctahedra, faces with six equivalent Mg(2)Y4Mg8 cuboctahedra, and faces with ten equivalent Mg(1)Y2Mg10 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(2), six equivalent Mg(1), and four equivalent Y(1) atoms to form distorted MgY4Mg8 cuboctahedra that share corners with six equivalent Mg(1)Y2Mg10 cuboctahedra, corners with six equivalent Mg(2)Y4Mg8 cuboctahedra, corners with six equivalent Y(1)Y6Mg6 cuboctahedra, edges with three equivalent Y(1)Y6Mg6 cuboctahedra, edges with seven equivalent Mg(1)Y2Mg10 cuboctahedra, edges with eight equivalent Mg(2)Y4Mg8 cuboctahedra, faces with six equivalent Mg(1)Y2Mg10 cuboctahedra, faces with six equivalent Mg(2)Y4Mg8 cuboctahedra, and faces with eight equivalent Y(1)Y6Mg6 cuboctahedra. Y(1) is bonded to two equivalent Mg(1), four equivalent Mg(2), and six equivalent Y(1) atoms to form YY6Mg6 cuboctahedra that share corners with six equivalent Mg(1)Y2Mg10 cuboctahedra, corners with six equivalent Mg(2)Y4Mg8 cuboctahedra, corners with six equivalent Y(1)Y6Mg6 cuboctahedra, edges with three equivalent Mg(2)Y4Mg8 cuboctahedra, edges with four equivalent Y(1)Y6Mg6 cuboctahedra, edges with eleven equivalent Mg(1)Y2Mg10 cuboctahedra, faces with four equivalent Mg(1)Y2Mg10 cuboctahedra, faces with eight equivalent Mg(2)Y4Mg8 cuboctahedra, and faces with eight equivalent Y(1)Y6Mg6 cuboctahedra. is represented by the CIF file [CIF]
data_YMg2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.632
_cell_length_b   8.632
_cell_length_c   5.477
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   156.698
_symmetry_Int_Tables_number   1
_cell_volume   161.428
_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  0.224  0.776  0.250  1.0
  Y  Y1  1  0.776  0.224  0.750  1.0
  Mg  Mg2  1  0.553  0.447  0.250  1.0
  Mg  Mg3  1  0.894  0.106  0.250  1.0
  Mg  Mg4  1  0.106  0.894  0.750  1.0
  Mg  Mg5  1  0.447  0.553  0.750  1.0
[/CIF]
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The compound described by Mg2Y is beta-derived structured and crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to four equivalent Mg(1), six equivalent Mg(2), and two equivalent Y(1) atoms to form distorted MgY2Mg10 cuboctahedra that share corners with six equivalent Mg(1)Y2Mg10 cuboctahedra, corners with six equivalent Mg(2)Y4Mg8 cuboctahedra, corners with six equivalent Y(1)Y6Mg6 cuboctahedra, edges with seven equivalent Mg(2)Y4Mg8 cuboctahedra, edges with eleven equivalent Y(1)Y6Mg6 cuboctahedra, faces with four equivalent Y(1)Y6Mg6 cuboctahedra, faces with six equivalent Mg(2)Y4Mg8 cuboctahedra, and faces with ten equivalent Mg(1)Y2Mg10 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(2), six equivalent Mg(1), and four equivalent Y(1) atoms to form distorted MgY4Mg8 cuboctahedra that share corners with six equivalent Mg(1)Y2Mg10 cuboctahedra, corners with six equivalent Mg(2)Y4Mg8 cuboctahedra, corners with six equivalent Y(1)Y6Mg6 cuboctahedra, edges with three equivalent Y(1)Y6Mg6 cuboctahedra, edges with seven equivalent Mg(1)Y2Mg10 cuboctahedra, edges with eight equivalent Mg(2)Y4Mg8 cuboctahedra, faces with six equivalent Mg(1)Y2Mg10 cuboctahedra, faces with six equivalent Mg(2)Y4Mg8 cuboctahedra, and faces with eight equivalent Y(1)Y6Mg6 cuboctahedra. Y(1) is bonded to two equivalent Mg(1), four equivalent Mg(2), and six equivalent Y(1) atoms to form YY6Mg6 cuboctahedra that share corners with six equivalent Mg(1)Y2Mg10 cuboctahedra, corners with six equivalent Mg(2)Y4Mg8 cuboctahedra, corners with six equivalent Y(1)Y6Mg6 cuboctahedra, edges with three equivalent Mg(2)Y4Mg8 cuboctahedra, edges with four equivalent Y(1)Y6Mg6 cuboctahedra, edges with eleven equivalent Mg(1)Y2Mg10 cuboctahedra, faces with four equivalent Mg(1)Y2Mg10 cuboctahedra, faces with eight equivalent Mg(2)Y4Mg8 cuboctahedra, and faces with eight equivalent Y(1)Y6Mg6 cuboctahedra. is represented by the CIF file [CIF]
data_YMg2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.632
_cell_length_b   8.632
_cell_length_c   5.477
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   156.698
_symmetry_Int_Tables_number   1
_cell_volume   161.428
_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  0.224  0.776  0.250  1.0
  Y  Y1  1  0.776  0.224  0.750  1.0
  Mg  Mg2  1  0.553  0.447  0.250  1.0
  Mg  Mg3  1  0.894  0.106  0.250  1.0
  Mg  Mg4  1  0.106  0.894  0.750  1.0
  Mg  Mg5  1  0.447  0.553  0.750  1.0
[/CIF]
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