The material structure described by MgY2Se4 crystallizes in the orthorhombic Pnma space group. Mg(1) is bonded in a trigonal pyramidal geometry to one Se(2), one Se(3), and two equivalent Se(1) atoms. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 7-coordinate geometry to one Se(2), two equivalent Se(3), and four equivalent Se(1) atoms. In the second Y site, Y(2) is bonded in a 6-coordinate geometry to one Se(2), one Se(3), and four equivalent Se(1) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to one Mg(1), two equivalent Y(1), and two equivalent Y(2) atoms. In the second Se site, Se(2) is bonded in a T-shaped geometry to one Mg(1), one Y(1), and one Y(2) atom. In the third Se site, Se(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Y(2), and two equivalent Y(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Y2MgSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.636
_cell_length_b   8.267
_cell_length_c   12.048
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   760.559
_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  0.750  0.052  0.314  1.0
  Y  Y1  1  0.250  0.948  0.686  1.0
  Y  Y2  1  0.250  0.448  0.814  1.0
  Y  Y3  1  0.750  0.552  0.186  1.0
  Y  Y4  1  0.250  0.066  0.019  1.0
  Y  Y5  1  0.750  0.934  0.981  1.0
  Y  Y6  1  0.750  0.434  0.519  1.0
  Y  Y7  1  0.250  0.566  0.481  1.0
  Mg  Mg8  1  0.250  0.182  0.407  1.0
  Mg  Mg9  1  0.750  0.818  0.593  1.0
  Mg  Mg10  1  0.750  0.318  0.907  1.0
  Mg  Mg11  1  0.250  0.682  0.093  1.0
  Se  Se12  1  0.499  0.127  0.842  1.0
  Se  Se13  1  0.501  0.873  0.158  1.0
  Se  Se14  1  0.501  0.373  0.342  1.0
  Se  Se15  1  0.499  0.627  0.658  1.0
  Se  Se16  1  0.001  0.627  0.658  1.0
  Se  Se17  1  0.999  0.373  0.342  1.0
  Se  Se18  1  0.999  0.873  0.158  1.0
  Se  Se19  1  0.001  0.127  0.842  1.0
  Se  Se20  1  0.250  0.892  0.450  1.0
  Se  Se21  1  0.750  0.108  0.550  1.0
  Se  Se22  1  0.750  0.608  0.950  1.0
  Se  Se23  1  0.250  0.392  0.050  1.0
  Se  Se24  1  0.750  0.228  0.112  1.0
  Se  Se25  1  0.250  0.772  0.888  1.0
  Se  Se26  1  0.250  0.272  0.612  1.0
  Se  Se27  1  0.750  0.728  0.388  1.0
[/CIF]
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The material structure described by MgY2Se4 crystallizes in the orthorhombic Pnma space group. Mg(1) is bonded in a trigonal pyramidal geometry to one Se(2), one Se(3), and two equivalent Se(1) atoms. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 7-coordinate geometry to one Se(2), two equivalent Se(3), and four equivalent Se(1) atoms. In the second Y site, Y(2) is bonded in a 6-coordinate geometry to one Se(2), one Se(3), and four equivalent Se(1) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to one Mg(1), two equivalent Y(1), and two equivalent Y(2) atoms. In the second Se site, Se(2) is bonded in a T-shaped geometry to one Mg(1), one Y(1), and one Y(2) atom. In the third Se site, Se(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Y(2), and two equivalent Y(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Y2MgSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.636
_cell_length_b   8.267
_cell_length_c   12.048
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   760.559
_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  0.750  0.052  0.314  1.0
  Y  Y1  1  0.250  0.948  0.686  1.0
  Y  Y2  1  0.250  0.448  0.814  1.0
  Y  Y3  1  0.750  0.552  0.186  1.0
  Y  Y4  1  0.250  0.066  0.019  1.0
  Y  Y5  1  0.750  0.934  0.981  1.0
  Y  Y6  1  0.750  0.434  0.519  1.0
  Y  Y7  1  0.250  0.566  0.481  1.0
  Mg  Mg8  1  0.250  0.182  0.407  1.0
  Mg  Mg9  1  0.750  0.818  0.593  1.0
  Mg  Mg10  1  0.750  0.318  0.907  1.0
  Mg  Mg11  1  0.250  0.682  0.093  1.0
  Se  Se12  1  0.499  0.127  0.842  1.0
  Se  Se13  1  0.501  0.873  0.158  1.0
  Se  Se14  1  0.501  0.373  0.342  1.0
  Se  Se15  1  0.499  0.627  0.658  1.0
  Se  Se16  1  0.001  0.627  0.658  1.0
  Se  Se17  1  0.999  0.373  0.342  1.0
  Se  Se18  1  0.999  0.873  0.158  1.0
  Se  Se19  1  0.001  0.127  0.842  1.0
  Se  Se20  1  0.250  0.892  0.450  1.0
  Se  Se21  1  0.750  0.108  0.550  1.0
  Se  Se22  1  0.750  0.608  0.950  1.0
  Se  Se23  1  0.250  0.392  0.050  1.0
  Se  Se24  1  0.750  0.228  0.112  1.0
  Se  Se25  1  0.250  0.772  0.888  1.0
  Se  Se26  1  0.250  0.272  0.612  1.0
  Se  Se27  1  0.750  0.728  0.388  1.0
[/CIF]
.