The material described by MgYS3 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent S(2) and four equivalent S(1) atoms to form MgS6 octahedra that share corners with eight equivalent Y(1)S4 tetrahedra and edges with three equivalent Mg(1)S6 octahedra. Y(1) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form distorted YS4 tetrahedra that share corners with eight equivalent Mg(1)S6 octahedra and  an edgeedge with one Y(1)S4 tetrahedra. The corner-sharing octahedral tilt angles range from 51-78°. There are two inequivalent S sites. In the first S site, S(1) is bonded in a 3-coordinate geometry to two equivalent Mg(1) and one Y(1) atom. In the second S site, S(2) is bonded to two equivalent Mg(1) and two equivalent Y(1) atoms to form edge-sharing SY2Mg2 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_YMgS3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.585
_cell_length_b   7.011
_cell_length_c   7.011
_cell_angle_alpha   62.300
_cell_angle_beta   76.490
_cell_angle_gamma   103.510
_symmetry_Int_Tables_number   1
_cell_volume   255.699
_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
  Mg  Mg0  1  1.000  0.662  0.662  1.0
  Mg  Mg1  1  1.000  0.338  0.338  1.0
  S  S2  1  0.808  0.889  0.779  1.0
  S  S3  1  0.192  0.111  0.221  1.0
  S  S4  1  0.192  0.779  0.889  1.0
  S  S5  1  0.808  0.221  0.111  1.0
  S  S6  1  0.264  0.551  0.449  1.0
  S  S7  1  0.736  0.449  0.551  1.0
  Y  Y8  1  0.702  0.798  0.202  1.0
  Y  Y9  1  0.298  0.202  0.798  1.0
[/CIF]
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The material described by MgYS3 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent S(2) and four equivalent S(1) atoms to form MgS6 octahedra that share corners with eight equivalent Y(1)S4 tetrahedra and edges with three equivalent Mg(1)S6 octahedra. Y(1) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form distorted YS4 tetrahedra that share corners with eight equivalent Mg(1)S6 octahedra and  an edgeedge with one Y(1)S4 tetrahedra. The corner-sharing octahedral tilt angles range from 51-78°. There are two inequivalent S sites. In the first S site, S(1) is bonded in a 3-coordinate geometry to two equivalent Mg(1) and one Y(1) atom. In the second S site, S(2) is bonded to two equivalent Mg(1) and two equivalent Y(1) atoms to form edge-sharing SY2Mg2 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_YMgS3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.585
_cell_length_b   7.011
_cell_length_c   7.011
_cell_angle_alpha   62.300
_cell_angle_beta   76.490
_cell_angle_gamma   103.510
_symmetry_Int_Tables_number   1
_cell_volume   255.699
_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
  Mg  Mg0  1  1.000  0.662  0.662  1.0
  Mg  Mg1  1  1.000  0.338  0.338  1.0
  S  S2  1  0.808  0.889  0.779  1.0
  S  S3  1  0.192  0.111  0.221  1.0
  S  S4  1  0.192  0.779  0.889  1.0
  S  S5  1  0.808  0.221  0.111  1.0
  S  S6  1  0.264  0.551  0.449  1.0
  S  S7  1  0.736  0.449  0.551  1.0
  Y  Y8  1  0.702  0.798  0.202  1.0
  Y  Y9  1  0.298  0.202  0.798  1.0
[/CIF]
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