The compound described by MgSm2S4 crystallizes in the orthorhombic Pnma space group. Mg(1) is bonded to two equivalent S(4) and three equivalent S(1) atoms to form MgS5 square pyramids that share corners with two equivalent Sm(1)S6 octahedra, corners with two equivalent Sm(2)S6 octahedra,  an edgeedge with one Sm(1)S6 octahedra, edges with three equivalent Sm(2)S6 octahedra, and edges with four equivalent Mg(1)S5 square pyramids. The corner-sharing octahedral tilt angles range from 4-5°. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded to one S(3), two equivalent S(4), and three equivalent S(2) atoms to form SmS6 octahedra that share corners with three equivalent Sm(2)S6 octahedra, corners with two equivalent Mg(1)S5 square pyramids, edges with two equivalent Sm(2)S6 octahedra, edges with four equivalent Sm(1)S6 octahedra, and  an edgeedge with one Mg(1)S5 square pyramid. The corner-sharing octahedral tilt angles range from 55-59°. In the second Sm site, Sm(2) is bonded to one S(2), one S(4), two equivalent S(1), and two equivalent S(3) atoms to form SmS6 octahedra that share corners with three equivalent Sm(1)S6 octahedra, corners with two equivalent Mg(1)S5 square pyramids, edges with two equivalent Sm(1)S6 octahedra, edges with two equivalent Sm(2)S6 octahedra, and edges with three equivalent Mg(1)S5 square pyramids. The corner-sharing octahedral tilt angles range from 55-59°. There are four inequivalent S sites. In the first S site, S(1) is bonded to three equivalent Mg(1) and two equivalent Sm(2) atoms to form SSm2Mg3 square pyramids that share corners with two equivalent S(4)Sm3Mg2 square pyramids, edges with three equivalent S(4)Sm3Mg2 square pyramids, and edges with four equivalent S(1)Sm2Mg3 square pyramids. In the second S site, S(2) is bonded in a rectangular see-saw-like geometry to one Sm(2) and three equivalent Sm(1) atoms. In the third S site, S(3) is bonded in a distorted T-shaped geometry to one Sm(1) and two equivalent Sm(2) atoms. In the fourth S site, S(4) is bonded to two equivalent Mg(1), one Sm(2), and two equivalent Sm(1) atoms to form SSm3Mg2 square pyramids that share corners with two equivalent S(1)Sm2Mg3 square pyramids, edges with two equivalent S(4)Sm3Mg2 square pyramids, and edges with three equivalent S(1)Sm2Mg3 square pyramids. is represented by the CIF card [CIF]
data_Sm2MgS4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.931
_cell_length_b   12.839
_cell_length_c   13.812
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   697.194
_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
  Sm  Sm0  1  0.250  0.121  0.074  1.0
  Sm  Sm1  1  0.750  0.879  0.926  1.0
  Sm  Sm2  1  0.750  0.379  0.574  1.0
  Sm  Sm3  1  0.250  0.621  0.426  1.0
  Sm  Sm4  1  0.250  0.134  0.707  1.0
  Sm  Sm5  1  0.750  0.866  0.293  1.0
  Sm  Sm6  1  0.750  0.366  0.207  1.0
  Sm  Sm7  1  0.250  0.634  0.793  1.0
  Mg  Mg8  1  0.750  0.108  0.459  1.0
  Mg  Mg9  1  0.250  0.892  0.541  1.0
  Mg  Mg10  1  0.250  0.392  0.959  1.0
  Mg  Mg11  1  0.750  0.608  0.041  1.0
  S  S12  1  0.750  0.003  0.614  1.0
  S  S13  1  0.250  0.997  0.386  1.0
  S  S14  1  0.250  0.497  0.114  1.0
  S  S15  1  0.750  0.503  0.886  1.0
  S  S16  1  0.250  0.025  0.885  1.0
  S  S17  1  0.750  0.975  0.115  1.0
  S  S18  1  0.750  0.475  0.385  1.0
  S  S19  1  0.250  0.525  0.615  1.0
  S  S20  1  0.250  0.229  0.246  1.0
  S  S21  1  0.750  0.771  0.754  1.0
  S  S22  1  0.750  0.271  0.746  1.0
  S  S23  1  0.250  0.729  0.254  1.0
  S  S24  1  0.750  0.267  0.016  1.0
  S  S25  1  0.250  0.733  0.984  1.0
  S  S26  1  0.250  0.233  0.516  1.0
  S  S27  1  0.750  0.767  0.484  1.0
[/CIF]
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The compound described by MgSm2S4 crystallizes in the orthorhombic Pnma space group. Mg(1) is bonded to two equivalent S(4) and three equivalent S(1) atoms to form MgS5 square pyramids that share corners with two equivalent Sm(1)S6 octahedra, corners with two equivalent Sm(2)S6 octahedra,  an edgeedge with one Sm(1)S6 octahedra, edges with three equivalent Sm(2)S6 octahedra, and edges with four equivalent Mg(1)S5 square pyramids. The corner-sharing octahedral tilt angles range from 4-5°. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded to one S(3), two equivalent S(4), and three equivalent S(2) atoms to form SmS6 octahedra that share corners with three equivalent Sm(2)S6 octahedra, corners with two equivalent Mg(1)S5 square pyramids, edges with two equivalent Sm(2)S6 octahedra, edges with four equivalent Sm(1)S6 octahedra, and  an edgeedge with one Mg(1)S5 square pyramid. The corner-sharing octahedral tilt angles range from 55-59°. In the second Sm site, Sm(2) is bonded to one S(2), one S(4), two equivalent S(1), and two equivalent S(3) atoms to form SmS6 octahedra that share corners with three equivalent Sm(1)S6 octahedra, corners with two equivalent Mg(1)S5 square pyramids, edges with two equivalent Sm(1)S6 octahedra, edges with two equivalent Sm(2)S6 octahedra, and edges with three equivalent Mg(1)S5 square pyramids. The corner-sharing octahedral tilt angles range from 55-59°. There are four inequivalent S sites. In the first S site, S(1) is bonded to three equivalent Mg(1) and two equivalent Sm(2) atoms to form SSm2Mg3 square pyramids that share corners with two equivalent S(4)Sm3Mg2 square pyramids, edges with three equivalent S(4)Sm3Mg2 square pyramids, and edges with four equivalent S(1)Sm2Mg3 square pyramids. In the second S site, S(2) is bonded in a rectangular see-saw-like geometry to one Sm(2) and three equivalent Sm(1) atoms. In the third S site, S(3) is bonded in a distorted T-shaped geometry to one Sm(1) and two equivalent Sm(2) atoms. In the fourth S site, S(4) is bonded to two equivalent Mg(1), one Sm(2), and two equivalent Sm(1) atoms to form SSm3Mg2 square pyramids that share corners with two equivalent S(1)Sm2Mg3 square pyramids, edges with two equivalent S(4)Sm3Mg2 square pyramids, and edges with three equivalent S(1)Sm2Mg3 square pyramids. is represented by the CIF card [CIF]
data_Sm2MgS4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.931
_cell_length_b   12.839
_cell_length_c   13.812
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   697.194
_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
  Sm  Sm0  1  0.250  0.121  0.074  1.0
  Sm  Sm1  1  0.750  0.879  0.926  1.0
  Sm  Sm2  1  0.750  0.379  0.574  1.0
  Sm  Sm3  1  0.250  0.621  0.426  1.0
  Sm  Sm4  1  0.250  0.134  0.707  1.0
  Sm  Sm5  1  0.750  0.866  0.293  1.0
  Sm  Sm6  1  0.750  0.366  0.207  1.0
  Sm  Sm7  1  0.250  0.634  0.793  1.0
  Mg  Mg8  1  0.750  0.108  0.459  1.0
  Mg  Mg9  1  0.250  0.892  0.541  1.0
  Mg  Mg10  1  0.250  0.392  0.959  1.0
  Mg  Mg11  1  0.750  0.608  0.041  1.0
  S  S12  1  0.750  0.003  0.614  1.0
  S  S13  1  0.250  0.997  0.386  1.0
  S  S14  1  0.250  0.497  0.114  1.0
  S  S15  1  0.750  0.503  0.886  1.0
  S  S16  1  0.250  0.025  0.885  1.0
  S  S17  1  0.750  0.975  0.115  1.0
  S  S18  1  0.750  0.475  0.385  1.0
  S  S19  1  0.250  0.525  0.615  1.0
  S  S20  1  0.250  0.229  0.246  1.0
  S  S21  1  0.750  0.771  0.754  1.0
  S  S22  1  0.750  0.271  0.746  1.0
  S  S23  1  0.250  0.729  0.254  1.0
  S  S24  1  0.750  0.267  0.016  1.0
  S  S25  1  0.250  0.733  0.984  1.0
  S  S26  1  0.250  0.233  0.516  1.0
  S  S27  1  0.750  0.767  0.484  1.0
[/CIF]
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