data_Y2Mg2Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.07
_cell_length_b   4.07
_cell_length_c   15.49
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Y2Mg2Cu
_chemical_formula_sum   'Y4 Mg4 Cu2'
_cell_volume   256.2
_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  Y6  1  0.0  0.0  0.74  1.0
  Y  Y7  1  0.03  0.03  0.74  1.0
  Y  Y8  1  0.03  0.0  0.92  1.0
  Y  Y9  1  0.0  0.03  0.57  1.0
  Mg  Mg2  1  0.0  0.0  0.0  1.0
  Mg  Mg3  1  0.03  0.03  0.0  1.0
  Mg  Mg4  1  0.03  0.0  0.11  1.0
  Mg  Mg5  1  0.0  0.03  0.38  1.0
  Cu  Cu0  1  0.03  0.0  0.27  1.0
  Cu  Cu1  1  0.0  0.03  0.21  1.0

data_Y2Mg2Cu
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.75
_cell_length_b   5.75
_cell_length_c   15.49
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Y2Mg2Cu
_chemical_formula_sum   'Y8 Mg8 Cu4'
_cell_volume   512.4
_cell_formula_units_Z   4
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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  4  0.02  0.02  0.74  1.0
  Y  Y1  2  0.0  0.0  0.57  1.0
  Y  Y2  2  0.03  0.0  0.92  1.0
  Mg  Mg3  4  0.02  0.02  0.0  1.0
  Mg  Mg4  2  0.0  0.0  0.38  1.0
  Mg  Mg5  2  0.03  0.0  0.11  1.0
  Cu  Cu6  2  0.0  0.0  0.21  1.0
  Cu  Cu7  2  0.03  0.0  0.27  1.0

Y Y Y Y Mg Mg Mg Mg Cu Cu
Y Y Y Y Mg Mg Mg Mg Cu Cu 0 1 o o o 0 3 o o o 1 3 o o o 2 4 o o + 2 5 o o + 3 7 o o o 4 5 o o o 4 6 o o o 5 6 o o o 6 9 o o o 7 8 o o o 8 9 o o o 
Mg2YY(MgCu)2(Y)2 crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two yttrium molecules, two Mg2Y clusters, and two Y(MgCu)2 clusters. In each Mg2Y cluster, Mg(1) is bonded in a single-bond geometry to one Mg(1) and one Y(2) atom. The Mg(1)-Mg(1) bond length is 0.19 Å. The Mg(1)-Y(2) bond length is 1.32 Å. Y(2) is bonded in a 2-coordinate geometry to two equivalent Mg(1) atoms. In each Y(MgCu)2 cluster, there are two inequivalent Mg sites. In the first Mg site, Mg(2) is bonded in a single-bond geometry to one Cu(2) atom. The Mg(2)-Cu(2) bond length is 1.59 Å. In the second Mg site, Mg(3) is bonded in a single-bond geometry to one Y(3) and one Cu(1) atom. The Mg(3)-Y(3) bond length is 3.02 Å. The Mg(3)-Cu(1) bond length is 1.59 Å. Y(3) is bonded in a distorted single-bond geometry to one Mg(3) atom. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a distorted bent 150 degrees geometry to one Mg(3) and one Cu(2) atom. The Cu(1)-Cu(2) bond length is 0.98 Å. In the second Cu site, Cu(2) is bonded in a distorted bent 150 degrees geometry to one Mg(2) and one Cu(1) atom.