The material described by Cu5Sn2Se7 is Enargite-like structured and crystallizes in the monoclinic C2 space group. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent Se(1) 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(3)Se4 tetrahedra. In the second Cu site, Cu(2) is bonded to one Se(2), one Se(3), and two equivalent Se(4) atoms to form CuSe4 tetrahedra that share  a cornercorner with one Cu(1)Se4 tetrahedra, corners with three equivalent Cu(2)Se4 tetrahedra, corners with three equivalent Cu(3)Se4 tetrahedra, and corners with five equivalent Sn(1)Se4 tetrahedra. In the third Cu site, Cu(3) is bonded to one Se(3), one Se(4), and two equivalent Se(1) atoms to form CuSe4 tetrahedra that share corners with two equivalent Cu(3)Se4 tetrahedra, corners with three equivalent Cu(1)Se4 tetrahedra, corners with three equivalent Cu(2)Se4 tetrahedra, and corners with four equivalent Sn(1)Se4 tetrahedra. Sn(1) is bonded to one Se(1), one Se(2), one Se(3), and one Se(4) atom to form SnSe4 tetrahedra that share  a cornercorner with one Sn(1)Se4 tetrahedra, corners with two equivalent Cu(1)Se4 tetrahedra, corners with four equivalent Cu(3)Se4 tetrahedra, and corners with five equivalent Cu(2)Se4 tetrahedra. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to one Cu(1), two equivalent Cu(3), and one Sn(1) atom to form SeCu3Sn tetrahedra that share  a cornercorner with one Se(2)Cu2Sn2 tetrahedra, corners with three equivalent Se(1)Cu3Sn tetrahedra, corners with three equivalent Se(4)Cu3Sn tetrahedra, and corners with five equivalent Se(3)Cu3Sn tetrahedra. In the second Se site, Se(2) is bonded to two equivalent Cu(2) and two equivalent Sn(1) atoms to form corner-sharing SeCu2Sn2 tetrahedra. In the third Se site, Se(3) is bonded to one Cu(1), one Cu(2), one Cu(3), and one Sn(1) atom to form SeCu3Sn tetrahedra that share  a cornercorner with one Se(3)Cu3Sn tetrahedra, corners with two equivalent Se(2)Cu2Sn2 tetrahedra, corners with four equivalent Se(4)Cu3Sn tetrahedra, and corners with five equivalent Se(1)Cu3Sn tetrahedra. In the fourth Se site, Se(4) is bonded to one Cu(3), two equivalent Cu(2), and one Sn(1) atom to form SeCu3Sn tetrahedra that share corners with two equivalent Se(4)Cu3Sn tetrahedra, corners with three equivalent Se(2)Cu2Sn2 tetrahedra, corners with three equivalent Se(1)Cu3Sn tetrahedra, and corners with four equivalent Se(3)Cu3Sn tetrahedra. is represented by the CIF card [CIF]
data_Cu5Sn2Se7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.939
_cell_length_b   6.939
_cell_length_c   8.962
_cell_angle_alpha   82.637
_cell_angle_beta   82.637
_cell_angle_gamma   48.104
_symmetry_Int_Tables_number   1
_cell_volume   318.081
_cell_formula_units_Z   1
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  0.732  0.268  0.500  1.0
  Cu  Cu1  1  0.887  0.405  0.074  1.0
  Cu  Cu2  1  0.595  0.113  0.926  1.0
  Cu  Cu3  1  0.448  0.978  0.357  1.0
  Cu  Cu4  1  0.022  0.552  0.643  1.0
  Sn  Sn5  1  0.149  0.702  0.224  1.0
  Sn  Sn6  1  0.298  0.851  0.776  1.0
  Se  Se7  1  0.353  0.351  0.442  1.0
  Se  Se8  1  0.649  0.647  0.558  1.0
  Se  Se9  1  0.511  0.489  0.000  1.0
  Se  Se10  1  0.049  0.111  0.291  1.0
  Se  Se11  1  0.889  0.951  0.709  1.0
  Se  Se12  1  0.745  0.808  0.139  1.0
  Se  Se13  1  0.192  0.255  0.861  1.0
[/CIF]
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The material described by Cu5Sn2Se7 is Enargite-like structured and crystallizes in the monoclinic C2 space group. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent Se(1) 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(3)Se4 tetrahedra. In the second Cu site, Cu(2) is bonded to one Se(2), one Se(3), and two equivalent Se(4) atoms to form CuSe4 tetrahedra that share  a cornercorner with one Cu(1)Se4 tetrahedra, corners with three equivalent Cu(2)Se4 tetrahedra, corners with three equivalent Cu(3)Se4 tetrahedra, and corners with five equivalent Sn(1)Se4 tetrahedra. In the third Cu site, Cu(3) is bonded to one Se(3), one Se(4), and two equivalent Se(1) atoms to form CuSe4 tetrahedra that share corners with two equivalent Cu(3)Se4 tetrahedra, corners with three equivalent Cu(1)Se4 tetrahedra, corners with three equivalent Cu(2)Se4 tetrahedra, and corners with four equivalent Sn(1)Se4 tetrahedra. Sn(1) is bonded to one Se(1), one Se(2), one Se(3), and one Se(4) atom to form SnSe4 tetrahedra that share  a cornercorner with one Sn(1)Se4 tetrahedra, corners with two equivalent Cu(1)Se4 tetrahedra, corners with four equivalent Cu(3)Se4 tetrahedra, and corners with five equivalent Cu(2)Se4 tetrahedra. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to one Cu(1), two equivalent Cu(3), and one Sn(1) atom to form SeCu3Sn tetrahedra that share  a cornercorner with one Se(2)Cu2Sn2 tetrahedra, corners with three equivalent Se(1)Cu3Sn tetrahedra, corners with three equivalent Se(4)Cu3Sn tetrahedra, and corners with five equivalent Se(3)Cu3Sn tetrahedra. In the second Se site, Se(2) is bonded to two equivalent Cu(2) and two equivalent Sn(1) atoms to form corner-sharing SeCu2Sn2 tetrahedra. In the third Se site, Se(3) is bonded to one Cu(1), one Cu(2), one Cu(3), and one Sn(1) atom to form SeCu3Sn tetrahedra that share  a cornercorner with one Se(3)Cu3Sn tetrahedra, corners with two equivalent Se(2)Cu2Sn2 tetrahedra, corners with four equivalent Se(4)Cu3Sn tetrahedra, and corners with five equivalent Se(1)Cu3Sn tetrahedra. In the fourth Se site, Se(4) is bonded to one Cu(3), two equivalent Cu(2), and one Sn(1) atom to form SeCu3Sn tetrahedra that share corners with two equivalent Se(4)Cu3Sn tetrahedra, corners with three equivalent Se(2)Cu2Sn2 tetrahedra, corners with three equivalent Se(1)Cu3Sn tetrahedra, and corners with four equivalent Se(3)Cu3Sn tetrahedra. is represented by the CIF card [CIF]
data_Cu5Sn2Se7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.939
_cell_length_b   6.939
_cell_length_c   8.962
_cell_angle_alpha   82.637
_cell_angle_beta   82.637
_cell_angle_gamma   48.104
_symmetry_Int_Tables_number   1
_cell_volume   318.081
_cell_formula_units_Z   1
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  0.732  0.268  0.500  1.0
  Cu  Cu1  1  0.887  0.405  0.074  1.0
  Cu  Cu2  1  0.595  0.113  0.926  1.0
  Cu  Cu3  1  0.448  0.978  0.357  1.0
  Cu  Cu4  1  0.022  0.552  0.643  1.0
  Sn  Sn5  1  0.149  0.702  0.224  1.0
  Sn  Sn6  1  0.298  0.851  0.776  1.0
  Se  Se7  1  0.353  0.351  0.442  1.0
  Se  Se8  1  0.649  0.647  0.558  1.0
  Se  Se9  1  0.511  0.489  0.000  1.0
  Se  Se10  1  0.049  0.111  0.291  1.0
  Se  Se11  1  0.889  0.951  0.709  1.0
  Se  Se12  1  0.745  0.808  0.139  1.0
  Se  Se13  1  0.192  0.255  0.861  1.0
[/CIF]
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