The compound described by MgEr2S4 crystallizes in the orthorhombic Pnma space group. Mg(1) is bonded in a trigonal pyramidal geometry to one S(2), one S(3), and two equivalent S(1) atoms. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 7-coordinate geometry to one S(2), two equivalent S(3), and four equivalent S(1) atoms. In the second Er site, Er(2) is bonded in a 6-coordinate geometry to one S(2), one S(3), and four equivalent S(1) atoms. There are three inequivalent S sites. In the first S site, S(1) is bonded in a 5-coordinate geometry to one Mg(1), two equivalent Er(1), and two equivalent Er(2) atoms. In the second S site, S(2) is bonded in a T-shaped geometry to one Mg(1), one Er(1), and one Er(2) atom. In the third S site, S(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Er(2), and two equivalent Er(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er2MgS4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.929
_cell_length_b   7.243
_cell_length_c   11.333
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.001
_symmetry_Int_Tables_number   1
_cell_volume   650.823
_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
  Er  Er0  1  0.035  0.750  0.311  1.0
  Er  Er1  1  0.965  0.250  0.689  1.0
  Er  Er2  1  0.465  0.250  0.811  1.0
  Er  Er3  1  0.535  0.750  0.189  1.0
  Er  Er4  1  0.075  0.250  0.021  1.0
  Er  Er5  1  0.925  0.750  0.979  1.0
  Er  Er6  1  0.425  0.750  0.521  1.0
  Er  Er7  1  0.575  0.250  0.479  1.0
  Mg  Mg8  1  0.185  0.250  0.409  1.0
  Mg  Mg9  1  0.815  0.750  0.591  1.0
  Mg  Mg10  1  0.315  0.750  0.909  1.0
  Mg  Mg11  1  0.685  0.250  0.091  1.0
  S  S12  1  0.130  0.500  0.843  1.0
  S  S13  1  0.870  0.500  0.157  1.0
  S  S14  1  0.370  0.500  0.343  1.0
  S  S15  1  0.630  0.500  0.657  1.0
  S  S16  1  0.630  0.000  0.657  1.0
  S  S17  1  0.370  1.000  0.343  1.0
  S  S18  1  0.870  1.000  0.157  1.0
  S  S19  1  0.130  0.000  0.843  1.0
  S  S20  1  0.898  0.250  0.455  1.0
  S  S21  1  0.102  0.750  0.545  1.0
  S  S22  1  0.602  0.750  0.955  1.0
  S  S23  1  0.398  0.250  0.045  1.0
  S  S24  1  0.216  0.750  0.112  1.0
  S  S25  1  0.784  0.250  0.888  1.0
  S  S26  1  0.284  0.250  0.612  1.0
  S  S27  1  0.716  0.750  0.388  1.0
[/CIF]
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The compound described by MgEr2S4 crystallizes in the orthorhombic Pnma space group. Mg(1) is bonded in a trigonal pyramidal geometry to one S(2), one S(3), and two equivalent S(1) atoms. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 7-coordinate geometry to one S(2), two equivalent S(3), and four equivalent S(1) atoms. In the second Er site, Er(2) is bonded in a 6-coordinate geometry to one S(2), one S(3), and four equivalent S(1) atoms. There are three inequivalent S sites. In the first S site, S(1) is bonded in a 5-coordinate geometry to one Mg(1), two equivalent Er(1), and two equivalent Er(2) atoms. In the second S site, S(2) is bonded in a T-shaped geometry to one Mg(1), one Er(1), and one Er(2) atom. In the third S site, S(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Er(2), and two equivalent Er(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er2MgS4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.929
_cell_length_b   7.243
_cell_length_c   11.333
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.001
_symmetry_Int_Tables_number   1
_cell_volume   650.823
_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
  Er  Er0  1  0.035  0.750  0.311  1.0
  Er  Er1  1  0.965  0.250  0.689  1.0
  Er  Er2  1  0.465  0.250  0.811  1.0
  Er  Er3  1  0.535  0.750  0.189  1.0
  Er  Er4  1  0.075  0.250  0.021  1.0
  Er  Er5  1  0.925  0.750  0.979  1.0
  Er  Er6  1  0.425  0.750  0.521  1.0
  Er  Er7  1  0.575  0.250  0.479  1.0
  Mg  Mg8  1  0.185  0.250  0.409  1.0
  Mg  Mg9  1  0.815  0.750  0.591  1.0
  Mg  Mg10  1  0.315  0.750  0.909  1.0
  Mg  Mg11  1  0.685  0.250  0.091  1.0
  S  S12  1  0.130  0.500  0.843  1.0
  S  S13  1  0.870  0.500  0.157  1.0
  S  S14  1  0.370  0.500  0.343  1.0
  S  S15  1  0.630  0.500  0.657  1.0
  S  S16  1  0.630  0.000  0.657  1.0
  S  S17  1  0.370  1.000  0.343  1.0
  S  S18  1  0.870  1.000  0.157  1.0
  S  S19  1  0.130  0.000  0.843  1.0
  S  S20  1  0.898  0.250  0.455  1.0
  S  S21  1  0.102  0.750  0.545  1.0
  S  S22  1  0.602  0.750  0.955  1.0
  S  S23  1  0.398  0.250  0.045  1.0
  S  S24  1  0.216  0.750  0.112  1.0
  S  S25  1  0.784  0.250  0.888  1.0
  S  S26  1  0.284  0.250  0.612  1.0
  S  S27  1  0.716  0.750  0.388  1.0
[/CIF]
.