The compound described by Cu2MgSiS4 is Stannite-like structured and crystallizes in the orthorhombic Pmn2_1 space group. Mg(1) is bonded to one S(2), one S(3), and two equivalent S(1) atoms to form MgS4 tetrahedra that share corners with four equivalent Si(1)S4 tetrahedra and corners with eight equivalent Cu(1)S4 tetrahedra. Cu(1) is bonded to one S(2), one S(3), and two equivalent S(1) atoms to form CuS4 tetrahedra that share corners with four equivalent Mg(1)S4 tetrahedra, corners with four equivalent Cu(1)S4 tetrahedra, and corners with four equivalent Si(1)S4 tetrahedra. Si(1) is bonded to one S(2), one S(3), and two equivalent S(1) atoms to form SiS4 tetrahedra that share corners with four equivalent Mg(1)S4 tetrahedra and corners with eight equivalent Cu(1)S4 tetrahedra. There are three inequivalent S sites. In the first S site, S(1) is bonded to one Mg(1), two equivalent Cu(1), and one Si(1) atom to form corner-sharing SMgCu2Si tetrahedra. In the second S site, S(2) is bonded to one Mg(1), two equivalent Cu(1), and one Si(1) atom to form corner-sharing SMgCu2Si tetrahedra. In the third S site, S(3) is bonded to one Mg(1), two equivalent Cu(1), and one Si(1) atom to form corner-sharing SMgCu2Si tetrahedra. is represented by the CIF file [CIF]
data_MgCu2SiS4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.204
_cell_length_b   6.458
_cell_length_c   7.567
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   303.155
_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  0.997  0.655  0.500  1.0
  Mg  Mg1  1  0.497  0.345  0.000  1.0
  Cu  Cu2  1  0.007  0.177  0.248  1.0
  Cu  Cu3  1  0.007  0.177  0.752  1.0
  Cu  Cu4  1  0.507  0.823  0.252  1.0
  Cu  Cu5  1  0.507  0.823  0.748  1.0
  Si  Si6  1  0.499  0.322  0.500  1.0
  Si  Si7  1  0.999  0.678  0.000  1.0
  S  S8  1  0.377  0.162  0.271  1.0
  S  S9  1  0.377  0.162  0.729  1.0
  S  S10  1  0.877  0.838  0.229  1.0
  S  S11  1  0.877  0.838  0.771  1.0
  S  S12  1  0.846  0.306  0.500  1.0
  S  S13  1  0.346  0.694  0.000  1.0
  S  S14  1  0.396  0.641  0.500  1.0
  S  S15  1  0.896  0.359  0.000  1.0
[/CIF]
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The compound described by Cu2MgSiS4 is Stannite-like structured and crystallizes in the orthorhombic Pmn2_1 space group. Mg(1) is bonded to one S(2), one S(3), and two equivalent S(1) atoms to form MgS4 tetrahedra that share corners with four equivalent Si(1)S4 tetrahedra and corners with eight equivalent Cu(1)S4 tetrahedra. Cu(1) is bonded to one S(2), one S(3), and two equivalent S(1) atoms to form CuS4 tetrahedra that share corners with four equivalent Mg(1)S4 tetrahedra, corners with four equivalent Cu(1)S4 tetrahedra, and corners with four equivalent Si(1)S4 tetrahedra. Si(1) is bonded to one S(2), one S(3), and two equivalent S(1) atoms to form SiS4 tetrahedra that share corners with four equivalent Mg(1)S4 tetrahedra and corners with eight equivalent Cu(1)S4 tetrahedra. There are three inequivalent S sites. In the first S site, S(1) is bonded to one Mg(1), two equivalent Cu(1), and one Si(1) atom to form corner-sharing SMgCu2Si tetrahedra. In the second S site, S(2) is bonded to one Mg(1), two equivalent Cu(1), and one Si(1) atom to form corner-sharing SMgCu2Si tetrahedra. In the third S site, S(3) is bonded to one Mg(1), two equivalent Cu(1), and one Si(1) atom to form corner-sharing SMgCu2Si tetrahedra. is represented by the CIF file [CIF]
data_MgCu2SiS4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.204
_cell_length_b   6.458
_cell_length_c   7.567
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   303.155
_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  0.997  0.655  0.500  1.0
  Mg  Mg1  1  0.497  0.345  0.000  1.0
  Cu  Cu2  1  0.007  0.177  0.248  1.0
  Cu  Cu3  1  0.007  0.177  0.752  1.0
  Cu  Cu4  1  0.507  0.823  0.252  1.0
  Cu  Cu5  1  0.507  0.823  0.748  1.0
  Si  Si6  1  0.499  0.322  0.500  1.0
  Si  Si7  1  0.999  0.678  0.000  1.0
  S  S8  1  0.377  0.162  0.271  1.0
  S  S9  1  0.377  0.162  0.729  1.0
  S  S10  1  0.877  0.838  0.229  1.0
  S  S11  1  0.877  0.838  0.771  1.0
  S  S12  1  0.846  0.306  0.500  1.0
  S  S13  1  0.346  0.694  0.000  1.0
  S  S14  1  0.396  0.641  0.500  1.0
  S  S15  1  0.896  0.359  0.000  1.0
[/CIF]
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