The material described by Cu2SnSe3 is Enargite-like structured and crystallizes in the orthorhombic Fdd2 space group. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one Se(1), one Se(2), and two equivalent Se(3) atoms to form CuSe4 tetrahedra that share corners with two equivalent Cu(1)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, corners with three equivalent Cu(3)Se4 tetrahedra, and corners with five equivalent Sn(1)Se4 tetrahedra. In the second Cu site, Cu(2) is bonded to two equivalent Se(1) and two equivalent Se(2) atoms to form CuSe4 tetrahedra that share corners with two equivalent Cu(3)Se4 tetrahedra, corners with four equivalent Cu(1)Se4 tetrahedra, and corners with six equivalent Sn(1)Se4 tetrahedra. In the third Cu site, Cu(3) is bonded to two equivalent Se(2) and two equivalent Se(3) atoms to form CuSe4 tetrahedra that share corners with two equivalent Cu(2)Se4 tetrahedra, corners with four equivalent Sn(1)Se4 tetrahedra, and corners with six equivalent Cu(1)Se4 tetrahedra. Sn(1) is bonded to one Se(2), one Se(3), and two equivalent Se(1) atoms to form SnSe4 tetrahedra that share corners with two equivalent Cu(3)Se4 tetrahedra, corners with two equivalent Sn(1)Se4 tetrahedra, corners with three equivalent Cu(2)Se4 tetrahedra, and corners with five equivalent Cu(1)Se4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to one Cu(1), one Cu(2), and two equivalent Sn(1) atoms to form SeCu2Sn2 tetrahedra that share corners with three equivalent Se(1)Cu2Sn2 tetrahedra, corners with four equivalent Se(3)Cu3Sn tetrahedra, and corners with five equivalent Se(2)Cu3Sn tetrahedra. In the second Se site, Se(2) is bonded to one Cu(1), one Cu(2), one Cu(3), and one Sn(1) atom to form SeCu3Sn tetrahedra that share corners with two equivalent Se(2)Cu3Sn tetrahedra, corners with five equivalent Se(1)Cu2Sn2 tetrahedra, and corners with five equivalent Se(3)Cu3Sn tetrahedra. In the third Se site, Se(3) is bonded to one Cu(3), two equivalent Cu(1), and one Sn(1) atom to form SeCu3Sn tetrahedra that share corners with three equivalent Se(3)Cu3Sn tetrahedra, corners with four equivalent Se(1)Cu2Sn2 tetrahedra, and corners with five equivalent Se(2)Cu3Sn tetrahedra. is represented by the CIF file [CIF]
data_Cu2SnSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.044
_cell_length_b   7.044
_cell_length_c   12.847
_cell_angle_alpha   79.368
_cell_angle_beta   100.632
_cell_angle_gamma   70.915
_symmetry_Int_Tables_number   1
_cell_volume   571.093
_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
  Cu  Cu0  1  0.264  0.243  0.500  1.0
  Cu  Cu1  1  0.908  0.575  0.833  1.0
  Cu  Cu2  1  0.577  0.931  0.167  1.0
  Cu  Cu3  1  0.348  0.660  0.667  1.0
  Cu  Cu4  1  0.993  0.015  1.000  1.0
  Cu  Cu5  1  0.658  0.325  0.333  1.0
  Cu  Cu6  1  0.417  0.084  0.833  1.0
  Cu  Cu7  1  0.167  0.834  0.333  1.0
  Sn  Sn8  1  0.099  0.400  0.174  1.0
  Sn  Sn9  1  0.734  0.765  0.493  1.0
  Sn  Sn10  1  0.824  0.175  0.674  1.0
  Sn  Sn11  1  0.509  0.490  0.993  1.0
  Se  Se12  1  0.105  0.649  0.989  1.0
  Se  Se13  1  0.798  0.969  0.323  1.0
  Se  Se14  1  0.431  0.299  0.667  1.0
  Se  Se15  1  0.632  0.097  0.000  1.0
  Se  Se16  1  0.303  0.465  0.344  1.0
  Se  Se17  1  0.982  0.772  0.677  1.0
  Se  Se18  1  0.059  0.209  0.844  1.0
  Se  Se19  1  0.699  0.555  0.177  1.0
  Se  Se20  1  0.347  0.882  0.500  1.0
  Se  Se21  1  0.888  0.366  0.489  1.0
  Se  Se22  1  0.542  0.726  0.823  1.0
  Se  Se23  1  0.216  0.014  0.167  1.0
[/CIF]
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The material described by Cu2SnSe3 is Enargite-like structured and crystallizes in the orthorhombic Fdd2 space group. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one Se(1), one Se(2), and two equivalent Se(3) atoms to form CuSe4 tetrahedra that share corners with two equivalent Cu(1)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, corners with three equivalent Cu(3)Se4 tetrahedra, and corners with five equivalent Sn(1)Se4 tetrahedra. In the second Cu site, Cu(2) is bonded to two equivalent Se(1) and two equivalent Se(2) atoms to form CuSe4 tetrahedra that share corners with two equivalent Cu(3)Se4 tetrahedra, corners with four equivalent Cu(1)Se4 tetrahedra, and corners with six equivalent Sn(1)Se4 tetrahedra. In the third Cu site, Cu(3) is bonded to two equivalent Se(2) and two equivalent Se(3) atoms to form CuSe4 tetrahedra that share corners with two equivalent Cu(2)Se4 tetrahedra, corners with four equivalent Sn(1)Se4 tetrahedra, and corners with six equivalent Cu(1)Se4 tetrahedra. Sn(1) is bonded to one Se(2), one Se(3), and two equivalent Se(1) atoms to form SnSe4 tetrahedra that share corners with two equivalent Cu(3)Se4 tetrahedra, corners with two equivalent Sn(1)Se4 tetrahedra, corners with three equivalent Cu(2)Se4 tetrahedra, and corners with five equivalent Cu(1)Se4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to one Cu(1), one Cu(2), and two equivalent Sn(1) atoms to form SeCu2Sn2 tetrahedra that share corners with three equivalent Se(1)Cu2Sn2 tetrahedra, corners with four equivalent Se(3)Cu3Sn tetrahedra, and corners with five equivalent Se(2)Cu3Sn tetrahedra. In the second Se site, Se(2) is bonded to one Cu(1), one Cu(2), one Cu(3), and one Sn(1) atom to form SeCu3Sn tetrahedra that share corners with two equivalent Se(2)Cu3Sn tetrahedra, corners with five equivalent Se(1)Cu2Sn2 tetrahedra, and corners with five equivalent Se(3)Cu3Sn tetrahedra. In the third Se site, Se(3) is bonded to one Cu(3), two equivalent Cu(1), and one Sn(1) atom to form SeCu3Sn tetrahedra that share corners with three equivalent Se(3)Cu3Sn tetrahedra, corners with four equivalent Se(1)Cu2Sn2 tetrahedra, and corners with five equivalent Se(2)Cu3Sn tetrahedra. is represented by the CIF file [CIF]
data_Cu2SnSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.044
_cell_length_b   7.044
_cell_length_c   12.847
_cell_angle_alpha   79.368
_cell_angle_beta   100.632
_cell_angle_gamma   70.915
_symmetry_Int_Tables_number   1
_cell_volume   571.093
_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
  Cu  Cu0  1  0.264  0.243  0.500  1.0
  Cu  Cu1  1  0.908  0.575  0.833  1.0
  Cu  Cu2  1  0.577  0.931  0.167  1.0
  Cu  Cu3  1  0.348  0.660  0.667  1.0
  Cu  Cu4  1  0.993  0.015  1.000  1.0
  Cu  Cu5  1  0.658  0.325  0.333  1.0
  Cu  Cu6  1  0.417  0.084  0.833  1.0
  Cu  Cu7  1  0.167  0.834  0.333  1.0
  Sn  Sn8  1  0.099  0.400  0.174  1.0
  Sn  Sn9  1  0.734  0.765  0.493  1.0
  Sn  Sn10  1  0.824  0.175  0.674  1.0
  Sn  Sn11  1  0.509  0.490  0.993  1.0
  Se  Se12  1  0.105  0.649  0.989  1.0
  Se  Se13  1  0.798  0.969  0.323  1.0
  Se  Se14  1  0.431  0.299  0.667  1.0
  Se  Se15  1  0.632  0.097  0.000  1.0
  Se  Se16  1  0.303  0.465  0.344  1.0
  Se  Se17  1  0.982  0.772  0.677  1.0
  Se  Se18  1  0.059  0.209  0.844  1.0
  Se  Se19  1  0.699  0.555  0.177  1.0
  Se  Se20  1  0.347  0.882  0.500  1.0
  Se  Se21  1  0.888  0.366  0.489  1.0
  Se  Se22  1  0.542  0.726  0.823  1.0
  Se  Se23  1  0.216  0.014  0.167  1.0
[/CIF]
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