The compound described by MnCuSe4 is Pyrite-derived structured and crystallizes in the monoclinic P2_1/c space group. Mn(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form MnSe6 octahedra that share corners with four equivalent Mn(1)Se6 octahedra, corners with eight equivalent Cu(1)Se6 octahedra, corners with two equivalent Se(2)MnCu2Se tetrahedra, and corners with four equivalent Se(1)Mn2CuSe tetrahedra. The corner-sharing octahedral tilt angles range from 64-67°. Cu(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form CuSe6 octahedra that share corners with four equivalent Cu(1)Se6 octahedra, corners with eight equivalent Mn(1)Se6 octahedra, corners with two equivalent Se(1)Mn2CuSe tetrahedra, and corners with four equivalent Se(2)MnCu2Se tetrahedra. The corner-sharing octahedral tilt angles range from 64-66°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Mn(1), one Cu(1), and one Se(1) atom to form distorted SeMn2CuSe tetrahedra that share  a cornercorner with one Cu(1)Se6 octahedra, corners with two equivalent Mn(1)Se6 octahedra, corners with seven equivalent Se(1)Mn2CuSe tetrahedra, and corners with eight equivalent Se(2)MnCu2Se tetrahedra. The corner-sharing octahedral tilt angles range from 74-78°. In the second Se site, Se(2) is bonded to one Mn(1), two equivalent Cu(1), and one Se(2) atom to form distorted SeMnCu2Se tetrahedra that share  a cornercorner with one Mn(1)Se6 octahedra, corners with two equivalent Cu(1)Se6 octahedra, corners with seven equivalent Se(2)MnCu2Se tetrahedra, and corners with eight equivalent Se(1)Mn2CuSe tetrahedra. The corner-sharing octahedral tilt angles range from 75-78°. is represented by the CIF card [CIF]
data_MnCuSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.257
_cell_length_b   6.236
_cell_length_c   6.249
_cell_angle_alpha   89.603
_cell_angle_beta   89.999
_cell_angle_gamma   90.008
_symmetry_Int_Tables_number   1
_cell_volume   243.812
_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
  Mn  Mn0  1  0.500  0.000  0.500  1.0
  Mn  Mn1  1  0.000  0.000  0.000  1.0
  Cu  Cu2  1  0.500  0.500  0.000  1.0
  Cu  Cu3  1  0.000  0.500  0.500  1.0
  Se  Se4  1  0.894  0.116  0.394  1.0
  Se  Se5  1  0.394  0.884  0.106  1.0
  Se  Se6  1  0.111  0.396  0.889  1.0
  Se  Se7  1  0.611  0.604  0.611  1.0
  Se  Se8  1  0.106  0.884  0.606  1.0
  Se  Se9  1  0.606  0.116  0.894  1.0
  Se  Se10  1  0.889  0.604  0.111  1.0
  Se  Se11  1  0.389  0.396  0.389  1.0
[/CIF]
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The compound described by MnCuSe4 is Pyrite-derived structured and crystallizes in the monoclinic P2_1/c space group. Mn(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form MnSe6 octahedra that share corners with four equivalent Mn(1)Se6 octahedra, corners with eight equivalent Cu(1)Se6 octahedra, corners with two equivalent Se(2)MnCu2Se tetrahedra, and corners with four equivalent Se(1)Mn2CuSe tetrahedra. The corner-sharing octahedral tilt angles range from 64-67°. Cu(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form CuSe6 octahedra that share corners with four equivalent Cu(1)Se6 octahedra, corners with eight equivalent Mn(1)Se6 octahedra, corners with two equivalent Se(1)Mn2CuSe tetrahedra, and corners with four equivalent Se(2)MnCu2Se tetrahedra. The corner-sharing octahedral tilt angles range from 64-66°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Mn(1), one Cu(1), and one Se(1) atom to form distorted SeMn2CuSe tetrahedra that share  a cornercorner with one Cu(1)Se6 octahedra, corners with two equivalent Mn(1)Se6 octahedra, corners with seven equivalent Se(1)Mn2CuSe tetrahedra, and corners with eight equivalent Se(2)MnCu2Se tetrahedra. The corner-sharing octahedral tilt angles range from 74-78°. In the second Se site, Se(2) is bonded to one Mn(1), two equivalent Cu(1), and one Se(2) atom to form distorted SeMnCu2Se tetrahedra that share  a cornercorner with one Mn(1)Se6 octahedra, corners with two equivalent Cu(1)Se6 octahedra, corners with seven equivalent Se(2)MnCu2Se tetrahedra, and corners with eight equivalent Se(1)Mn2CuSe tetrahedra. The corner-sharing octahedral tilt angles range from 75-78°. is represented by the CIF card [CIF]
data_MnCuSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.257
_cell_length_b   6.236
_cell_length_c   6.249
_cell_angle_alpha   89.603
_cell_angle_beta   89.999
_cell_angle_gamma   90.008
_symmetry_Int_Tables_number   1
_cell_volume   243.812
_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
  Mn  Mn0  1  0.500  0.000  0.500  1.0
  Mn  Mn1  1  0.000  0.000  0.000  1.0
  Cu  Cu2  1  0.500  0.500  0.000  1.0
  Cu  Cu3  1  0.000  0.500  0.500  1.0
  Se  Se4  1  0.894  0.116  0.394  1.0
  Se  Se5  1  0.394  0.884  0.106  1.0
  Se  Se6  1  0.111  0.396  0.889  1.0
  Se  Se7  1  0.611  0.604  0.611  1.0
  Se  Se8  1  0.106  0.884  0.606  1.0
  Se  Se9  1  0.606  0.116  0.894  1.0
  Se  Se10  1  0.889  0.604  0.111  1.0
  Se  Se11  1  0.389  0.396  0.389  1.0
[/CIF]
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