The material described by YMg4Cu crystallizes in the orthorhombic Cmmm space group. There are six inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 11-coordinate geometry to one Mg(5), two equivalent Mg(2), four equivalent Mg(3), and four equivalent Mg(4) atoms. In the second Mg site, Mg(2) is bonded in a distorted water-like geometry to one Mg(1) and two equivalent Cu(1) atoms. In the third Mg site, Mg(3) is bonded in a distorted single-bond geometry to two equivalent Mg(1), two equivalent Mg(5), and one Cu(1) atom. In the fourth Mg site, Mg(4) is bonded in a distorted single-bond geometry to two equivalent Mg(1) and one Cu(1) atom. In the fifth Mg site, Mg(5) is bonded in a 10-coordinate geometry to two equivalent Mg(1) and eight equivalent Mg(3) atoms. In the sixth Mg site, Mg(6) is bonded in a distorted square co-planar geometry to four equivalent Cu(1) atoms. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 4-coordinate geometry to four equivalent Cu(1) atoms. In the second Y site, Y(2) is bonded in a 4-coordinate geometry to four equivalent Cu(1) atoms. Cu(1) is bonded in a 9-coordinate geometry to one Mg(3), one Mg(4), one Mg(6), two equivalent Mg(2), two equivalent Y(1), and two equivalent Y(2) atoms. is represented by the CIF file [CIF]
data_YMg4Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.969
_cell_length_b   11.969
_cell_length_c   4.047
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   112.818
_symmetry_Int_Tables_number   1
_cell_volume   534.289
_cell_formula_units_Z   4
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  0.699  0.699  0.000  1.0
  Y  Y1  1  0.301  0.301  0.000  1.0
  Y  Y2  1  0.633  0.367  0.000  1.0
  Y  Y3  1  0.367  0.633  0.000  1.0
  Mg  Mg4  1  0.835  0.165  0.000  1.0
  Mg  Mg5  1  0.413  0.077  0.000  1.0
  Mg  Mg6  1  0.211  0.050  0.500  1.0
  Mg  Mg7  1  0.375  0.865  0.500  1.0
  Mg  Mg8  1  0.050  0.211  0.500  1.0
  Mg  Mg9  1  0.587  0.923  0.000  1.0
  Mg  Mg10  1  0.950  0.789  0.500  1.0
  Mg  Mg11  1  0.165  0.835  0.000  1.0
  Mg  Mg12  1  0.625  0.135  0.500  1.0
  Mg  Mg13  1  0.135  0.625  0.500  1.0
  Mg  Mg14  1  0.077  0.413  0.000  1.0
  Mg  Mg15  1  0.865  0.375  0.500  1.0
  Mg  Mg16  1  0.789  0.950  0.500  1.0
  Mg  Mg17  1  0.923  0.587  0.000  1.0
  Mg  Mg18  1  0.000  0.000  0.000  1.0
  Mg  Mg19  1  0.500  0.500  0.500  1.0
  Cu  Cu20  1  0.765  0.554  0.500  1.0
  Cu  Cu21  1  0.554  0.765  0.500  1.0
  Cu  Cu22  1  0.446  0.235  0.500  1.0
  Cu  Cu23  1  0.235  0.446  0.500  1.0
[/CIF]
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The material described by YMg4Cu crystallizes in the orthorhombic Cmmm space group. There are six inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 11-coordinate geometry to one Mg(5), two equivalent Mg(2), four equivalent Mg(3), and four equivalent Mg(4) atoms. In the second Mg site, Mg(2) is bonded in a distorted water-like geometry to one Mg(1) and two equivalent Cu(1) atoms. In the third Mg site, Mg(3) is bonded in a distorted single-bond geometry to two equivalent Mg(1), two equivalent Mg(5), and one Cu(1) atom. In the fourth Mg site, Mg(4) is bonded in a distorted single-bond geometry to two equivalent Mg(1) and one Cu(1) atom. In the fifth Mg site, Mg(5) is bonded in a 10-coordinate geometry to two equivalent Mg(1) and eight equivalent Mg(3) atoms. In the sixth Mg site, Mg(6) is bonded in a distorted square co-planar geometry to four equivalent Cu(1) atoms. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 4-coordinate geometry to four equivalent Cu(1) atoms. In the second Y site, Y(2) is bonded in a 4-coordinate geometry to four equivalent Cu(1) atoms. Cu(1) is bonded in a 9-coordinate geometry to one Mg(3), one Mg(4), one Mg(6), two equivalent Mg(2), two equivalent Y(1), and two equivalent Y(2) atoms. is represented by the CIF file [CIF]
data_YMg4Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.969
_cell_length_b   11.969
_cell_length_c   4.047
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   112.818
_symmetry_Int_Tables_number   1
_cell_volume   534.289
_cell_formula_units_Z   4
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  0.699  0.699  0.000  1.0
  Y  Y1  1  0.301  0.301  0.000  1.0
  Y  Y2  1  0.633  0.367  0.000  1.0
  Y  Y3  1  0.367  0.633  0.000  1.0
  Mg  Mg4  1  0.835  0.165  0.000  1.0
  Mg  Mg5  1  0.413  0.077  0.000  1.0
  Mg  Mg6  1  0.211  0.050  0.500  1.0
  Mg  Mg7  1  0.375  0.865  0.500  1.0
  Mg  Mg8  1  0.050  0.211  0.500  1.0
  Mg  Mg9  1  0.587  0.923  0.000  1.0
  Mg  Mg10  1  0.950  0.789  0.500  1.0
  Mg  Mg11  1  0.165  0.835  0.000  1.0
  Mg  Mg12  1  0.625  0.135  0.500  1.0
  Mg  Mg13  1  0.135  0.625  0.500  1.0
  Mg  Mg14  1  0.077  0.413  0.000  1.0
  Mg  Mg15  1  0.865  0.375  0.500  1.0
  Mg  Mg16  1  0.789  0.950  0.500  1.0
  Mg  Mg17  1  0.923  0.587  0.000  1.0
  Mg  Mg18  1  0.000  0.000  0.000  1.0
  Mg  Mg19  1  0.500  0.500  0.500  1.0
  Cu  Cu20  1  0.765  0.554  0.500  1.0
  Cu  Cu21  1  0.554  0.765  0.500  1.0
  Cu  Cu22  1  0.446  0.235  0.500  1.0
  Cu  Cu23  1  0.235  0.446  0.500  1.0
[/CIF]
.