The crystal structure described by MgYb2Se4 crystallizes in the orthorhombic Pnma space group. Mg(1) is bonded in a rectangular see-saw-like geometry to one Se(2), one Se(3), and two equivalent Se(1) atoms. There are two inequivalent Yb sites. In the first Yb site, Yb(1) is bonded to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form YbSe6 octahedra that share corners with two equivalent Yb(2)Se7 pentagonal bipyramids, edges with two equivalent Yb(1)Se6 octahedra, and edges with four equivalent Yb(2)Se7 pentagonal bipyramids. In the second Yb site, Yb(2) is bonded to one Se(2), two equivalent Se(3), and four equivalent Se(1) atoms to form distorted YbSe7 pentagonal bipyramids that share corners with two equivalent Yb(1)Se6 octahedra, corners with six equivalent Yb(2)Se7 pentagonal bipyramids, and edges with four equivalent Yb(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 48°. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 4-coordinate geometry to one Mg(1), one Yb(1), and two equivalent Yb(2) atoms. In the second Se site, Se(2) is bonded to one Mg(1), one Yb(2), and two equivalent Yb(1) atoms to form distorted SeYb3Mg trigonal pyramids that share corners with three equivalent Se(3)Yb4Mg trigonal bipyramids, corners with two equivalent Se(2)Yb3Mg trigonal pyramids, and edges with two equivalent Se(3)Yb4Mg trigonal bipyramids. In the third Se site, Se(3) is bonded to one Mg(1), two equivalent Yb(1), and two equivalent Yb(2) atoms to form SeYb4Mg trigonal bipyramids that share corners with four equivalent Se(3)Yb4Mg trigonal bipyramids, corners with three equivalent Se(2)Yb3Mg trigonal pyramids, and edges with two equivalent Se(2)Yb3Mg trigonal pyramids. is represented by the CIF card [CIF]
data_Yb2MgSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.337
_cell_length_b   9.026
_cell_length_c   7.468
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   764.215
_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
  Yb  Yb0  1  0.000  0.000  0.500  1.0
  Yb  Yb1  1  0.500  0.000  0.000  1.0
  Yb  Yb2  1  0.500  0.500  0.000  1.0
  Yb  Yb3  1  0.000  0.500  0.500  1.0
  Yb  Yb4  1  0.212  0.750  0.918  1.0
  Yb  Yb5  1  0.788  0.250  0.082  1.0
  Yb  Yb6  1  0.288  0.250  0.418  1.0
  Yb  Yb7  1  0.712  0.750  0.582  1.0
  Mg  Mg8  1  0.114  0.250  0.944  1.0
  Mg  Mg9  1  0.886  0.750  0.056  1.0
  Mg  Mg10  1  0.386  0.750  0.444  1.0
  Mg  Mg11  1  0.614  0.250  0.556  1.0
  Se  Se12  1  0.201  0.050  0.745  1.0
  Se  Se13  1  0.799  0.950  0.255  1.0
  Se  Se14  1  0.299  0.950  0.245  1.0
  Se  Se15  1  0.701  0.050  0.755  1.0
  Se  Se16  1  0.701  0.450  0.755  1.0
  Se  Se17  1  0.299  0.550  0.245  1.0
  Se  Se18  1  0.799  0.550  0.255  1.0
  Se  Se19  1  0.201  0.450  0.745  1.0
  Se  Se20  1  0.078  0.750  0.251  1.0
  Se  Se21  1  0.922  0.250  0.749  1.0
  Se  Se22  1  0.422  0.250  0.751  1.0
  Se  Se23  1  0.578  0.750  0.249  1.0
  Se  Se24  1  0.045  0.250  0.264  1.0
  Se  Se25  1  0.955  0.750  0.736  1.0
  Se  Se26  1  0.455  0.750  0.764  1.0
  Se  Se27  1  0.545  0.250  0.236  1.0
[/CIF]
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The crystal structure described by MgYb2Se4 crystallizes in the orthorhombic Pnma space group. Mg(1) is bonded in a rectangular see-saw-like geometry to one Se(2), one Se(3), and two equivalent Se(1) atoms. There are two inequivalent Yb sites. In the first Yb site, Yb(1) is bonded to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form YbSe6 octahedra that share corners with two equivalent Yb(2)Se7 pentagonal bipyramids, edges with two equivalent Yb(1)Se6 octahedra, and edges with four equivalent Yb(2)Se7 pentagonal bipyramids. In the second Yb site, Yb(2) is bonded to one Se(2), two equivalent Se(3), and four equivalent Se(1) atoms to form distorted YbSe7 pentagonal bipyramids that share corners with two equivalent Yb(1)Se6 octahedra, corners with six equivalent Yb(2)Se7 pentagonal bipyramids, and edges with four equivalent Yb(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 48°. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 4-coordinate geometry to one Mg(1), one Yb(1), and two equivalent Yb(2) atoms. In the second Se site, Se(2) is bonded to one Mg(1), one Yb(2), and two equivalent Yb(1) atoms to form distorted SeYb3Mg trigonal pyramids that share corners with three equivalent Se(3)Yb4Mg trigonal bipyramids, corners with two equivalent Se(2)Yb3Mg trigonal pyramids, and edges with two equivalent Se(3)Yb4Mg trigonal bipyramids. In the third Se site, Se(3) is bonded to one Mg(1), two equivalent Yb(1), and two equivalent Yb(2) atoms to form SeYb4Mg trigonal bipyramids that share corners with four equivalent Se(3)Yb4Mg trigonal bipyramids, corners with three equivalent Se(2)Yb3Mg trigonal pyramids, and edges with two equivalent Se(2)Yb3Mg trigonal pyramids. is represented by the CIF card [CIF]
data_Yb2MgSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.337
_cell_length_b   9.026
_cell_length_c   7.468
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   764.215
_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
  Yb  Yb0  1  0.000  0.000  0.500  1.0
  Yb  Yb1  1  0.500  0.000  0.000  1.0
  Yb  Yb2  1  0.500  0.500  0.000  1.0
  Yb  Yb3  1  0.000  0.500  0.500  1.0
  Yb  Yb4  1  0.212  0.750  0.918  1.0
  Yb  Yb5  1  0.788  0.250  0.082  1.0
  Yb  Yb6  1  0.288  0.250  0.418  1.0
  Yb  Yb7  1  0.712  0.750  0.582  1.0
  Mg  Mg8  1  0.114  0.250  0.944  1.0
  Mg  Mg9  1  0.886  0.750  0.056  1.0
  Mg  Mg10  1  0.386  0.750  0.444  1.0
  Mg  Mg11  1  0.614  0.250  0.556  1.0
  Se  Se12  1  0.201  0.050  0.745  1.0
  Se  Se13  1  0.799  0.950  0.255  1.0
  Se  Se14  1  0.299  0.950  0.245  1.0
  Se  Se15  1  0.701  0.050  0.755  1.0
  Se  Se16  1  0.701  0.450  0.755  1.0
  Se  Se17  1  0.299  0.550  0.245  1.0
  Se  Se18  1  0.799  0.550  0.255  1.0
  Se  Se19  1  0.201  0.450  0.745  1.0
  Se  Se20  1  0.078  0.750  0.251  1.0
  Se  Se21  1  0.922  0.250  0.749  1.0
  Se  Se22  1  0.422  0.250  0.751  1.0
  Se  Se23  1  0.578  0.750  0.249  1.0
  Se  Se24  1  0.045  0.250  0.264  1.0
  Se  Se25  1  0.955  0.750  0.736  1.0
  Se  Se26  1  0.455  0.750  0.764  1.0
  Se  Se27  1  0.545  0.250  0.236  1.0
[/CIF]
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