The compound described by Mg6LaY crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 8-coordinate geometry to two equivalent Mg(3), two equivalent Mg(4), two equivalent La(1), and two equivalent Y(1) atoms. In the second Mg site, Mg(2) is bonded in a 8-coordinate geometry to two equivalent Mg(3), two equivalent Mg(4), two equivalent La(1), and two equivalent Y(1) atoms. In the third Mg site, Mg(3) is bonded to four equivalent Mg(1), four equivalent Mg(2), two equivalent La(1), and two equivalent Y(1) atoms to form MgLa2Y2Mg8 cuboctahedra that share corners with four equivalent Mg(3)La2Y2Mg8 cuboctahedra, corners with eight equivalent Mg(4)La2Y2Mg8 cuboctahedra, edges with four equivalent La(1)Mg12 cuboctahedra, edges with four equivalent Y(1)Mg12 cuboctahedra, faces with two equivalent Mg(3)La2Y2Mg8 cuboctahedra, faces with two equivalent La(1)Mg12 cuboctahedra, faces with two equivalent Y(1)Mg12 cuboctahedra, and faces with four equivalent Mg(4)La2Y2Mg8 cuboctahedra. In the fourth Mg site, Mg(4) is bonded to four equivalent Mg(1), four equivalent Mg(2), two equivalent La(1), and two equivalent Y(1) atoms to form MgLa2Y2Mg8 cuboctahedra that share corners with four equivalent Mg(4)La2Y2Mg8 cuboctahedra, corners with eight equivalent Mg(3)La2Y2Mg8 cuboctahedra, edges with four equivalent La(1)Mg12 cuboctahedra, edges with four equivalent Y(1)Mg12 cuboctahedra, faces with two equivalent Mg(4)La2Y2Mg8 cuboctahedra, faces with two equivalent La(1)Mg12 cuboctahedra, faces with two equivalent Y(1)Mg12 cuboctahedra, and faces with four equivalent Mg(3)La2Y2Mg8 cuboctahedra. La(1) is bonded to two equivalent Mg(3), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(2) atoms to form distorted LaMg12 cuboctahedra that share corners with four equivalent La(1)Mg12 cuboctahedra, corners with eight equivalent Y(1)Mg12 cuboctahedra, edges with four equivalent Mg(3)La2Y2Mg8 cuboctahedra, edges with four equivalent Mg(4)La2Y2Mg8 cuboctahedra, faces with two equivalent Mg(3)La2Y2Mg8 cuboctahedra, faces with two equivalent Mg(4)La2Y2Mg8 cuboctahedra, faces with two equivalent La(1)Mg12 cuboctahedra, and faces with four equivalent Y(1)Mg12 cuboctahedra. Y(1) is bonded to two equivalent Mg(3), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(2) atoms to form distorted YMg12 cuboctahedra that share corners with four equivalent Y(1)Mg12 cuboctahedra, corners with eight equivalent La(1)Mg12 cuboctahedra, edges with four equivalent Mg(3)La2Y2Mg8 cuboctahedra, edges with four equivalent Mg(4)La2Y2Mg8 cuboctahedra, faces with two equivalent Mg(3)La2Y2Mg8 cuboctahedra, faces with two equivalent Mg(4)La2Y2Mg8 cuboctahedra, faces with two equivalent Y(1)Mg12 cuboctahedra, and faces with four equivalent La(1)Mg12 cuboctahedra. is represented by the CIF file [CIF]
data_LaYMg6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.025
_cell_length_b   6.561
_cell_length_c   6.561
_cell_angle_alpha   100.159
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   212.938
_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
  La  La0  1  0.500  0.624  0.376  1.0
  Mg  Mg1  1  0.500  0.634  0.878  1.0
  Mg  Mg2  1  0.500  0.122  0.366  1.0
  Mg  Mg3  1  1.000  0.882  0.642  1.0
  Mg  Mg4  1  1.000  0.358  0.118  1.0
  Mg  Mg5  1  0.000  0.374  0.626  1.0
  Mg  Mg6  1  0.000  0.876  0.124  1.0
  Y  Y7  1  0.500  0.131  0.869  1.0
[/CIF]
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The compound described by Mg6LaY crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 8-coordinate geometry to two equivalent Mg(3), two equivalent Mg(4), two equivalent La(1), and two equivalent Y(1) atoms. In the second Mg site, Mg(2) is bonded in a 8-coordinate geometry to two equivalent Mg(3), two equivalent Mg(4), two equivalent La(1), and two equivalent Y(1) atoms. In the third Mg site, Mg(3) is bonded to four equivalent Mg(1), four equivalent Mg(2), two equivalent La(1), and two equivalent Y(1) atoms to form MgLa2Y2Mg8 cuboctahedra that share corners with four equivalent Mg(3)La2Y2Mg8 cuboctahedra, corners with eight equivalent Mg(4)La2Y2Mg8 cuboctahedra, edges with four equivalent La(1)Mg12 cuboctahedra, edges with four equivalent Y(1)Mg12 cuboctahedra, faces with two equivalent Mg(3)La2Y2Mg8 cuboctahedra, faces with two equivalent La(1)Mg12 cuboctahedra, faces with two equivalent Y(1)Mg12 cuboctahedra, and faces with four equivalent Mg(4)La2Y2Mg8 cuboctahedra. In the fourth Mg site, Mg(4) is bonded to four equivalent Mg(1), four equivalent Mg(2), two equivalent La(1), and two equivalent Y(1) atoms to form MgLa2Y2Mg8 cuboctahedra that share corners with four equivalent Mg(4)La2Y2Mg8 cuboctahedra, corners with eight equivalent Mg(3)La2Y2Mg8 cuboctahedra, edges with four equivalent La(1)Mg12 cuboctahedra, edges with four equivalent Y(1)Mg12 cuboctahedra, faces with two equivalent Mg(4)La2Y2Mg8 cuboctahedra, faces with two equivalent La(1)Mg12 cuboctahedra, faces with two equivalent Y(1)Mg12 cuboctahedra, and faces with four equivalent Mg(3)La2Y2Mg8 cuboctahedra. La(1) is bonded to two equivalent Mg(3), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(2) atoms to form distorted LaMg12 cuboctahedra that share corners with four equivalent La(1)Mg12 cuboctahedra, corners with eight equivalent Y(1)Mg12 cuboctahedra, edges with four equivalent Mg(3)La2Y2Mg8 cuboctahedra, edges with four equivalent Mg(4)La2Y2Mg8 cuboctahedra, faces with two equivalent Mg(3)La2Y2Mg8 cuboctahedra, faces with two equivalent Mg(4)La2Y2Mg8 cuboctahedra, faces with two equivalent La(1)Mg12 cuboctahedra, and faces with four equivalent Y(1)Mg12 cuboctahedra. Y(1) is bonded to two equivalent Mg(3), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(2) atoms to form distorted YMg12 cuboctahedra that share corners with four equivalent Y(1)Mg12 cuboctahedra, corners with eight equivalent La(1)Mg12 cuboctahedra, edges with four equivalent Mg(3)La2Y2Mg8 cuboctahedra, edges with four equivalent Mg(4)La2Y2Mg8 cuboctahedra, faces with two equivalent Mg(3)La2Y2Mg8 cuboctahedra, faces with two equivalent Mg(4)La2Y2Mg8 cuboctahedra, faces with two equivalent Y(1)Mg12 cuboctahedra, and faces with four equivalent La(1)Mg12 cuboctahedra. is represented by the CIF file [CIF]
data_LaYMg6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.025
_cell_length_b   6.561
_cell_length_c   6.561
_cell_angle_alpha   100.159
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   212.938
_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
  La  La0  1  0.500  0.624  0.376  1.0
  Mg  Mg1  1  0.500  0.634  0.878  1.0
  Mg  Mg2  1  0.500  0.122  0.366  1.0
  Mg  Mg3  1  1.000  0.882  0.642  1.0
  Mg  Mg4  1  1.000  0.358  0.118  1.0
  Mg  Mg5  1  0.000  0.374  0.626  1.0
  Mg  Mg6  1  0.000  0.876  0.124  1.0
  Y  Y7  1  0.500  0.131  0.869  1.0
[/CIF]
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