The compound described by MgY3 is alpha La-derived structured and crystallizes in the tetragonal I4/mmm space group. Mg(1) is bonded to four equivalent Y(1) and eight equivalent Y(2) atoms to form MgY12 cuboctahedra that share corners with four equivalent Mg(1)Y12 cuboctahedra, corners with eight equivalent Y(1)Y8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Y12 cuboctahedra, edges with sixteen equivalent Y(2)Y8Mg4 cuboctahedra, faces with four equivalent Mg(1)Y12 cuboctahedra, faces with six equivalent Y(1)Y8Mg4 cuboctahedra, and faces with eight equivalent Y(2)Y8Mg4 cuboctahedra. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to four equivalent Mg(1) and eight equivalent Y(2) atoms to form YY8Mg4 cuboctahedra that share corners with four equivalent Y(1)Y8Mg4 cuboctahedra, corners with eight equivalent Mg(1)Y12 cuboctahedra, edges with eight equivalent Y(1)Y8Mg4 cuboctahedra, edges with sixteen equivalent Y(2)Y8Mg4 cuboctahedra, faces with four equivalent Y(1)Y8Mg4 cuboctahedra, faces with six equivalent Mg(1)Y12 cuboctahedra, and faces with eight equivalent Y(2)Y8Mg4 cuboctahedra. In the second Y site, Y(2) is bonded to four equivalent Mg(1), four equivalent Y(1), and four equivalent Y(2) atoms to form YY8Mg4 cuboctahedra that share corners with twelve equivalent Y(2)Y8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Y12 cuboctahedra, edges with eight equivalent Y(1)Y8Mg4 cuboctahedra, edges with eight equivalent Y(2)Y8Mg4 cuboctahedra, faces with four equivalent Mg(1)Y12 cuboctahedra, faces with four equivalent Y(1)Y8Mg4 cuboctahedra, and faces with ten equivalent Y(2)Y8Mg4 cuboctahedra. is represented by the CIF card [CIF]
data_Y3Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.021
_cell_length_b   6.021
_cell_length_c   6.021
_cell_angle_alpha   131.393
_cell_angle_beta   131.393
_cell_angle_gamma   71.189
_symmetry_Int_Tables_number   1
_cell_volume   120.281
_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  0.500  0.500  0.000  1.0
  Y  Y1  1  0.250  0.750  0.500  1.0
  Y  Y2  1  0.750  0.250  0.500  1.0
  Mg  Mg3  1  0.000  0.000  0.000  1.0
[/CIF]
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The compound described by MgY3 is alpha La-derived structured and crystallizes in the tetragonal I4/mmm space group. Mg(1) is bonded to four equivalent Y(1) and eight equivalent Y(2) atoms to form MgY12 cuboctahedra that share corners with four equivalent Mg(1)Y12 cuboctahedra, corners with eight equivalent Y(1)Y8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Y12 cuboctahedra, edges with sixteen equivalent Y(2)Y8Mg4 cuboctahedra, faces with four equivalent Mg(1)Y12 cuboctahedra, faces with six equivalent Y(1)Y8Mg4 cuboctahedra, and faces with eight equivalent Y(2)Y8Mg4 cuboctahedra. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to four equivalent Mg(1) and eight equivalent Y(2) atoms to form YY8Mg4 cuboctahedra that share corners with four equivalent Y(1)Y8Mg4 cuboctahedra, corners with eight equivalent Mg(1)Y12 cuboctahedra, edges with eight equivalent Y(1)Y8Mg4 cuboctahedra, edges with sixteen equivalent Y(2)Y8Mg4 cuboctahedra, faces with four equivalent Y(1)Y8Mg4 cuboctahedra, faces with six equivalent Mg(1)Y12 cuboctahedra, and faces with eight equivalent Y(2)Y8Mg4 cuboctahedra. In the second Y site, Y(2) is bonded to four equivalent Mg(1), four equivalent Y(1), and four equivalent Y(2) atoms to form YY8Mg4 cuboctahedra that share corners with twelve equivalent Y(2)Y8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Y12 cuboctahedra, edges with eight equivalent Y(1)Y8Mg4 cuboctahedra, edges with eight equivalent Y(2)Y8Mg4 cuboctahedra, faces with four equivalent Mg(1)Y12 cuboctahedra, faces with four equivalent Y(1)Y8Mg4 cuboctahedra, and faces with ten equivalent Y(2)Y8Mg4 cuboctahedra. is represented by the CIF card [CIF]
data_Y3Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.021
_cell_length_b   6.021
_cell_length_c   6.021
_cell_angle_alpha   131.393
_cell_angle_beta   131.393
_cell_angle_gamma   71.189
_symmetry_Int_Tables_number   1
_cell_volume   120.281
_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  0.500  0.500  0.000  1.0
  Y  Y1  1  0.250  0.750  0.500  1.0
  Y  Y2  1  0.750  0.250  0.500  1.0
  Mg  Mg3  1  0.000  0.000  0.000  1.0
[/CIF]
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