The compound described by MgY3 crystallizes in the orthorhombic Pmm2 space group. Mg(1) is bonded in a 10-coordinate geometry to two equivalent Y(1), four equivalent Y(2), and four equivalent Y(3) atoms. There are three inequivalent Y sites. In the first Y site, Y(1) is bonded to two equivalent Mg(1), two equivalent Y(1), four equivalent Y(2), and four equivalent Y(3) atoms to form YY10Mg2 cuboctahedra that share corners with eight equivalent Y(2)Y8Mg4 cuboctahedra, corners with ten equivalent Y(1)Y10Mg2 cuboctahedra, edges with two equivalent Y(1)Y10Mg2 cuboctahedra, edges with four equivalent Y(2)Y8Mg4 cuboctahedra, edges with eight equivalent Y(3)Y8Mg4 cuboctahedra, faces with four equivalent Y(1)Y10Mg2 cuboctahedra, faces with four equivalent Y(2)Y8Mg4 cuboctahedra, and faces with four equivalent Y(3)Y8Mg4 cuboctahedra. In the second Y site, Y(2) is bonded to four equivalent Mg(1), two equivalent Y(2), two equivalent Y(3), and four equivalent Y(1) atoms to form YY8Mg4 cuboctahedra that share corners with eight equivalent Y(1)Y10Mg2 cuboctahedra, corners with ten equivalent Y(2)Y8Mg4 cuboctahedra, edges with two equivalent Y(2)Y8Mg4 cuboctahedra, edges with four equivalent Y(1)Y10Mg2 cuboctahedra, edges with four equivalent Y(3)Y8Mg4 cuboctahedra, faces with four equivalent Y(1)Y10Mg2 cuboctahedra, faces with four equivalent Y(2)Y8Mg4 cuboctahedra, and faces with eight equivalent Y(3)Y8Mg4 cuboctahedra. In the third Y site, Y(3) is bonded to four equivalent Mg(1), two equivalent Y(2), two equivalent Y(3), and four equivalent Y(1) atoms to form YY8Mg4 cuboctahedra that share corners with ten equivalent Y(3)Y8Mg4 cuboctahedra, edges with two equivalent Y(3)Y8Mg4 cuboctahedra, edges with four equivalent Y(2)Y8Mg4 cuboctahedra, edges with eight equivalent Y(1)Y10Mg2 cuboctahedra, faces with four equivalent Y(1)Y10Mg2 cuboctahedra, faces with four equivalent Y(3)Y8Mg4 cuboctahedra, and faces with eight equivalent Y(2)Y8Mg4 cuboctahedra. is represented by the CIF file [CIF]
data_Y3Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.577
_cell_length_b   5.691
_cell_length_c   6.116
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   124.514
_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  0.000  0.000  0.005  1.0
  Y  Y1  1  0.500  0.000  0.490  1.0
  Y  Y2  1  0.500  0.500  0.842  1.0
  Mg  Mg3  1  0.000  0.500  0.330  1.0
[/CIF]
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The compound described by MgY3 crystallizes in the orthorhombic Pmm2 space group. Mg(1) is bonded in a 10-coordinate geometry to two equivalent Y(1), four equivalent Y(2), and four equivalent Y(3) atoms. There are three inequivalent Y sites. In the first Y site, Y(1) is bonded to two equivalent Mg(1), two equivalent Y(1), four equivalent Y(2), and four equivalent Y(3) atoms to form YY10Mg2 cuboctahedra that share corners with eight equivalent Y(2)Y8Mg4 cuboctahedra, corners with ten equivalent Y(1)Y10Mg2 cuboctahedra, edges with two equivalent Y(1)Y10Mg2 cuboctahedra, edges with four equivalent Y(2)Y8Mg4 cuboctahedra, edges with eight equivalent Y(3)Y8Mg4 cuboctahedra, faces with four equivalent Y(1)Y10Mg2 cuboctahedra, faces with four equivalent Y(2)Y8Mg4 cuboctahedra, and faces with four equivalent Y(3)Y8Mg4 cuboctahedra. In the second Y site, Y(2) is bonded to four equivalent Mg(1), two equivalent Y(2), two equivalent Y(3), and four equivalent Y(1) atoms to form YY8Mg4 cuboctahedra that share corners with eight equivalent Y(1)Y10Mg2 cuboctahedra, corners with ten equivalent Y(2)Y8Mg4 cuboctahedra, edges with two equivalent Y(2)Y8Mg4 cuboctahedra, edges with four equivalent Y(1)Y10Mg2 cuboctahedra, edges with four equivalent Y(3)Y8Mg4 cuboctahedra, faces with four equivalent Y(1)Y10Mg2 cuboctahedra, faces with four equivalent Y(2)Y8Mg4 cuboctahedra, and faces with eight equivalent Y(3)Y8Mg4 cuboctahedra. In the third Y site, Y(3) is bonded to four equivalent Mg(1), two equivalent Y(2), two equivalent Y(3), and four equivalent Y(1) atoms to form YY8Mg4 cuboctahedra that share corners with ten equivalent Y(3)Y8Mg4 cuboctahedra, edges with two equivalent Y(3)Y8Mg4 cuboctahedra, edges with four equivalent Y(2)Y8Mg4 cuboctahedra, edges with eight equivalent Y(1)Y10Mg2 cuboctahedra, faces with four equivalent Y(1)Y10Mg2 cuboctahedra, faces with four equivalent Y(3)Y8Mg4 cuboctahedra, and faces with eight equivalent Y(2)Y8Mg4 cuboctahedra. is represented by the CIF file [CIF]
data_Y3Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.577
_cell_length_b   5.691
_cell_length_c   6.116
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   124.514
_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  0.000  0.000  0.005  1.0
  Y  Y1  1  0.500  0.000  0.490  1.0
  Y  Y2  1  0.500  0.500  0.842  1.0
  Mg  Mg3  1  0.000  0.500  0.330  1.0
[/CIF]
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