The compound described by Y5Cu5Mg16 crystallizes in the orthorhombic Cmcm space group. There are nine inequivalent Mg sites. In the first Mg site, Mg(9) is bonded in a distorted L-shaped geometry to two equivalent Cu(2) atoms. In the second Mg site, Mg(1) is bonded in a distorted single-bond geometry to two equivalent Mg(6) and one Cu(1) atom. In the third Mg site, Mg(2) is bonded in a water-like geometry to one Mg(6) and two equivalent Cu(1) atoms. In the fourth Mg site, Mg(3) is bonded in a distorted water-like geometry to two equivalent Cu(2) atoms. In the fifth Mg site, Mg(4) is bonded in a distorted single-bond geometry to three equivalent Mg(6) and one Cu(1) atom. In the sixth Mg site, Mg(5) is bonded in a 4-coordinate geometry to one Cu(1), one Cu(2), and two equivalent Cu(3) atoms. In the seventh Mg site, Mg(6) is bonded to one Mg(2), two equivalent Mg(1), two equivalent Mg(6), three equivalent Mg(4), three equivalent Mg(7), and one Y(2) atom to form distorted face-sharing MgYMg11 cuboctahedra. In the eighth Mg site, Mg(7) is bonded in a distorted single-bond geometry to three equivalent Mg(6) and one Cu(2) atom. In the ninth Mg site, Mg(8) is bonded in a distorted water-like geometry to two equivalent Cu(3) atoms. There are three inequivalent Y sites. In the first Y site, Y(1) is bonded in a 3-coordinate geometry to one Cu(3) and two equivalent Cu(1) atoms. In the second Y site, Y(2) is bonded in a 4-coordinate geometry to one Mg(6), two equivalent Cu(1), and two equivalent Cu(2) atoms. In the third Y site, Y(3) is bonded in a 5-coordinate geometry to one Cu(3) and four equivalent Cu(2) atoms. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 9-coordinate geometry to one Mg(1), one Mg(4), one Mg(5), two equivalent Mg(2), two equivalent Y(1), and two equivalent Y(2) atoms. In the second Cu site, Cu(2) is bonded in a 9-coordinate geometry to one Mg(5), one Mg(7), one Mg(9), two equivalent Mg(3), two equivalent Y(2), and two equivalent Y(3) atoms. In the third Cu site, Cu(3) is bonded in a 9-coordinate geometry to two equivalent Mg(8), four equivalent Mg(5), one Y(3), and two equivalent Y(1) atoms. is represented by the CIF file [CIF]
data_Y5Mg16Cu5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.769
_cell_length_b   9.769
_cell_length_c   28.893
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   155.452
_symmetry_Int_Tables_number   1
_cell_volume   1145.609
_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  0.396  0.604  0.657  1.0
  Y  Y1  1  0.588  0.412  0.623  1.0
  Y  Y2  1  0.412  0.588  0.123  1.0
  Y  Y3  1  0.412  0.588  0.377  1.0
  Y  Y4  1  0.628  0.372  0.750  1.0
  Y  Y5  1  0.604  0.396  0.157  1.0
  Y  Y6  1  0.604  0.396  0.343  1.0
  Y  Y7  1  0.372  0.628  0.250  1.0
  Y  Y8  1  0.396  0.604  0.843  1.0
  Y  Y9  1  0.588  0.412  0.877  1.0
  Mg  Mg10  1  0.925  0.075  0.032  1.0
  Mg  Mg11  1  0.453  0.547  0.546  1.0
  Mg  Mg12  1  0.757  0.243  0.832  1.0
  Mg  Mg13  1  0.162  0.838  0.070  1.0
  Mg  Mg14  1  0.018  0.982  0.696  1.0
  Mg  Mg15  1  0.691  0.309  0.989  1.0
  Mg  Mg16  1  0.075  0.925  0.968  1.0
  Mg  Mg17  1  0.222  0.778  0.909  1.0
  Mg  Mg18  1  0.122  0.878  0.250  1.0
  Mg  Mg19  1  0.838  0.162  0.930  1.0
  Mg  Mg20  1  0.018  0.982  0.804  1.0
  Mg  Mg21  1  0.309  0.691  0.011  1.0
  Mg  Mg22  1  0.309  0.691  0.489  1.0
  Mg  Mg23  1  0.547  0.453  0.046  1.0
  Mg  Mg24  1  0.243  0.757  0.168  1.0
  Mg  Mg25  1  0.878  0.122  0.750  1.0
  Mg  Mg26  1  0.266  0.734  0.750  1.0
  Mg  Mg27  1  0.982  0.018  0.196  1.0
  Mg  Mg28  1  0.778  0.222  0.091  1.0
  Mg  Mg29  1  0.547  0.453  0.454  1.0
  Mg  Mg30  1  0.243  0.757  0.332  1.0
  Mg  Mg31  1  0.778  0.222  0.409  1.0
  Mg  Mg32  1  0.838  0.162  0.570  1.0
  Mg  Mg33  1  0.222  0.778  0.591  1.0
  Mg  Mg34  1  0.075  0.925  0.532  1.0
  Mg  Mg35  1  0.982  0.018  0.304  1.0
  Mg  Mg36  1  0.691  0.309  0.511  1.0
  Mg  Mg37  1  0.162  0.838  0.430  1.0
  Mg  Mg38  1  0.925  0.075  0.468  1.0
  Mg  Mg39  1  0.757  0.243  0.668  1.0
  Mg  Mg40  1  0.453  0.547  0.954  1.0
  Mg  Mg41  1  0.734  0.266  0.250  1.0
  Cu  Cu42  1  0.025  0.975  0.104  1.0
  Cu  Cu43  1  0.835  0.165  0.179  1.0
  Cu  Cu44  1  0.165  0.835  0.679  1.0
  Cu  Cu45  1  0.471  0.529  0.750  1.0
  Cu  Cu46  1  0.975  0.025  0.604  1.0
  Cu  Cu47  1  0.529  0.471  0.250  1.0
  Cu  Cu48  1  0.975  0.025  0.896  1.0
  Cu  Cu49  1  0.835  0.165  0.321  1.0
  Cu  Cu50  1  0.165  0.835  0.821  1.0
  Cu  Cu51  1  0.025  0.975  0.396  1.0
[/CIF]
.
The compound described by Y5Cu5Mg16 crystallizes in the orthorhombic Cmcm space group. There are nine inequivalent Mg sites. In the first Mg site, Mg(9) is bonded in a distorted L-shaped geometry to two equivalent Cu(2) atoms. In the second Mg site, Mg(1) is bonded in a distorted single-bond geometry to two equivalent Mg(6) and one Cu(1) atom. In the third Mg site, Mg(2) is bonded in a water-like geometry to one Mg(6) and two equivalent Cu(1) atoms. In the fourth Mg site, Mg(3) is bonded in a distorted water-like geometry to two equivalent Cu(2) atoms. In the fifth Mg site, Mg(4) is bonded in a distorted single-bond geometry to three equivalent Mg(6) and one Cu(1) atom. In the sixth Mg site, Mg(5) is bonded in a 4-coordinate geometry to one Cu(1), one Cu(2), and two equivalent Cu(3) atoms. In the seventh Mg site, Mg(6) is bonded to one Mg(2), two equivalent Mg(1), two equivalent Mg(6), three equivalent Mg(4), three equivalent Mg(7), and one Y(2) atom to form distorted face-sharing MgYMg11 cuboctahedra. In the eighth Mg site, Mg(7) is bonded in a distorted single-bond geometry to three equivalent Mg(6) and one Cu(2) atom. In the ninth Mg site, Mg(8) is bonded in a distorted water-like geometry to two equivalent Cu(3) atoms. There are three inequivalent Y sites. In the first Y site, Y(1) is bonded in a 3-coordinate geometry to one Cu(3) and two equivalent Cu(1) atoms. In the second Y site, Y(2) is bonded in a 4-coordinate geometry to one Mg(6), two equivalent Cu(1), and two equivalent Cu(2) atoms. In the third Y site, Y(3) is bonded in a 5-coordinate geometry to one Cu(3) and four equivalent Cu(2) atoms. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 9-coordinate geometry to one Mg(1), one Mg(4), one Mg(5), two equivalent Mg(2), two equivalent Y(1), and two equivalent Y(2) atoms. In the second Cu site, Cu(2) is bonded in a 9-coordinate geometry to one Mg(5), one Mg(7), one Mg(9), two equivalent Mg(3), two equivalent Y(2), and two equivalent Y(3) atoms. In the third Cu site, Cu(3) is bonded in a 9-coordinate geometry to two equivalent Mg(8), four equivalent Mg(5), one Y(3), and two equivalent Y(1) atoms. is represented by the CIF file [CIF]
data_Y5Mg16Cu5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.769
_cell_length_b   9.769
_cell_length_c   28.893
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   155.452
_symmetry_Int_Tables_number   1
_cell_volume   1145.609
_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  0.396  0.604  0.657  1.0
  Y  Y1  1  0.588  0.412  0.623  1.0
  Y  Y2  1  0.412  0.588  0.123  1.0
  Y  Y3  1  0.412  0.588  0.377  1.0
  Y  Y4  1  0.628  0.372  0.750  1.0
  Y  Y5  1  0.604  0.396  0.157  1.0
  Y  Y6  1  0.604  0.396  0.343  1.0
  Y  Y7  1  0.372  0.628  0.250  1.0
  Y  Y8  1  0.396  0.604  0.843  1.0
  Y  Y9  1  0.588  0.412  0.877  1.0
  Mg  Mg10  1  0.925  0.075  0.032  1.0
  Mg  Mg11  1  0.453  0.547  0.546  1.0
  Mg  Mg12  1  0.757  0.243  0.832  1.0
  Mg  Mg13  1  0.162  0.838  0.070  1.0
  Mg  Mg14  1  0.018  0.982  0.696  1.0
  Mg  Mg15  1  0.691  0.309  0.989  1.0
  Mg  Mg16  1  0.075  0.925  0.968  1.0
  Mg  Mg17  1  0.222  0.778  0.909  1.0
  Mg  Mg18  1  0.122  0.878  0.250  1.0
  Mg  Mg19  1  0.838  0.162  0.930  1.0
  Mg  Mg20  1  0.018  0.982  0.804  1.0
  Mg  Mg21  1  0.309  0.691  0.011  1.0
  Mg  Mg22  1  0.309  0.691  0.489  1.0
  Mg  Mg23  1  0.547  0.453  0.046  1.0
  Mg  Mg24  1  0.243  0.757  0.168  1.0
  Mg  Mg25  1  0.878  0.122  0.750  1.0
  Mg  Mg26  1  0.266  0.734  0.750  1.0
  Mg  Mg27  1  0.982  0.018  0.196  1.0
  Mg  Mg28  1  0.778  0.222  0.091  1.0
  Mg  Mg29  1  0.547  0.453  0.454  1.0
  Mg  Mg30  1  0.243  0.757  0.332  1.0
  Mg  Mg31  1  0.778  0.222  0.409  1.0
  Mg  Mg32  1  0.838  0.162  0.570  1.0
  Mg  Mg33  1  0.222  0.778  0.591  1.0
  Mg  Mg34  1  0.075  0.925  0.532  1.0
  Mg  Mg35  1  0.982  0.018  0.304  1.0
  Mg  Mg36  1  0.691  0.309  0.511  1.0
  Mg  Mg37  1  0.162  0.838  0.430  1.0
  Mg  Mg38  1  0.925  0.075  0.468  1.0
  Mg  Mg39  1  0.757  0.243  0.668  1.0
  Mg  Mg40  1  0.453  0.547  0.954  1.0
  Mg  Mg41  1  0.734  0.266  0.250  1.0
  Cu  Cu42  1  0.025  0.975  0.104  1.0
  Cu  Cu43  1  0.835  0.165  0.179  1.0
  Cu  Cu44  1  0.165  0.835  0.679  1.0
  Cu  Cu45  1  0.471  0.529  0.750  1.0
  Cu  Cu46  1  0.975  0.025  0.604  1.0
  Cu  Cu47  1  0.529  0.471  0.250  1.0
  Cu  Cu48  1  0.975  0.025  0.896  1.0
  Cu  Cu49  1  0.835  0.165  0.321  1.0
  Cu  Cu50  1  0.165  0.835  0.821  1.0
  Cu  Cu51  1  0.025  0.975  0.396  1.0
[/CIF]
.