The material described by Cu4SiP8 crystallizes in the tetragonal I4_1/a space group. Cu(1) is bonded in a 4-coordinate geometry to one P(2) and three equivalent P(1) atoms. Si(1) is bonded to four equivalent P(1) atoms to form SiP4 tetrahedra that share corners with four equivalent P(2)CuP3 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to three equivalent Cu(1), one Si(1), and one P(2) atom to form distorted PCu3SiP trigonal bipyramids that share corners with five equivalent P(2)CuP3 tetrahedra, corners with seven equivalent P(1)Cu3SiP trigonal bipyramids, and  an edgeedge with one P(1)Cu3SiP trigonal bipyramid. In the second P site, P(2) is bonded to one Cu(1), one P(1), and two equivalent P(2) atoms to form distorted PCuP3 tetrahedra that share  a cornercorner with one Si(1)P4 tetrahedra, corners with two equivalent P(2)CuP3 tetrahedra, and corners with five equivalent P(1)Cu3SiP trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cu4SiP8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.062
_cell_length_b   9.062
_cell_length_c   9.063
_cell_angle_alpha   95.659
_cell_angle_beta   95.661
_cell_angle_gamma   143.392
_symmetry_Int_Tables_number   1
_cell_volume   421.329
_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
  Cu  Cu0  1  0.362  0.577  0.810  1.0
  Cu  Cu1  1  0.802  0.112  0.286  1.0
  Cu  Cu2  1  0.827  0.517  0.715  1.0
  Cu  Cu3  1  0.767  0.552  0.190  1.0
  Cu  Cu4  1  0.888  0.173  0.690  1.0
  Cu  Cu5  1  0.448  0.638  0.214  1.0
  Cu  Cu6  1  0.423  0.233  0.785  1.0
  Cu  Cu7  1  0.483  0.198  0.310  1.0
  Si  Si8  1  0.250  0.750  0.500  1.0
  Si  Si9  1  1.000  1.000  1.000  1.0
  P  P10  1  0.360  0.157  0.026  1.0
  P  P11  1  0.407  0.882  0.297  1.0
  P  P12  1  0.665  0.640  0.797  1.0
  P  P13  1  0.118  0.415  0.526  1.0
  P  P14  1  0.890  0.593  0.474  1.0
  P  P15  1  0.843  0.868  0.203  1.0
  P  P16  1  0.585  0.110  0.703  1.0
  P  P17  1  0.132  0.335  0.974  1.0
  P  P18  1  0.075  0.956  0.574  1.0
  P  P19  1  0.751  0.825  0.619  1.0
  P  P20  1  0.206  0.133  0.381  1.0
  P  P21  1  0.383  0.501  0.426  1.0
  P  P22  1  0.175  0.794  0.926  1.0
  P  P23  1  0.499  0.925  0.881  1.0
  P  P24  1  0.044  0.617  0.119  1.0
  P  P25  1  0.867  0.249  0.074  1.0
[/CIF]
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The material described by Cu4SiP8 crystallizes in the tetragonal I4_1/a space group. Cu(1) is bonded in a 4-coordinate geometry to one P(2) and three equivalent P(1) atoms. Si(1) is bonded to four equivalent P(1) atoms to form SiP4 tetrahedra that share corners with four equivalent P(2)CuP3 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to three equivalent Cu(1), one Si(1), and one P(2) atom to form distorted PCu3SiP trigonal bipyramids that share corners with five equivalent P(2)CuP3 tetrahedra, corners with seven equivalent P(1)Cu3SiP trigonal bipyramids, and  an edgeedge with one P(1)Cu3SiP trigonal bipyramid. In the second P site, P(2) is bonded to one Cu(1), one P(1), and two equivalent P(2) atoms to form distorted PCuP3 tetrahedra that share  a cornercorner with one Si(1)P4 tetrahedra, corners with two equivalent P(2)CuP3 tetrahedra, and corners with five equivalent P(1)Cu3SiP trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cu4SiP8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.062
_cell_length_b   9.062
_cell_length_c   9.063
_cell_angle_alpha   95.659
_cell_angle_beta   95.661
_cell_angle_gamma   143.392
_symmetry_Int_Tables_number   1
_cell_volume   421.329
_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
  Cu  Cu0  1  0.362  0.577  0.810  1.0
  Cu  Cu1  1  0.802  0.112  0.286  1.0
  Cu  Cu2  1  0.827  0.517  0.715  1.0
  Cu  Cu3  1  0.767  0.552  0.190  1.0
  Cu  Cu4  1  0.888  0.173  0.690  1.0
  Cu  Cu5  1  0.448  0.638  0.214  1.0
  Cu  Cu6  1  0.423  0.233  0.785  1.0
  Cu  Cu7  1  0.483  0.198  0.310  1.0
  Si  Si8  1  0.250  0.750  0.500  1.0
  Si  Si9  1  1.000  1.000  1.000  1.0
  P  P10  1  0.360  0.157  0.026  1.0
  P  P11  1  0.407  0.882  0.297  1.0
  P  P12  1  0.665  0.640  0.797  1.0
  P  P13  1  0.118  0.415  0.526  1.0
  P  P14  1  0.890  0.593  0.474  1.0
  P  P15  1  0.843  0.868  0.203  1.0
  P  P16  1  0.585  0.110  0.703  1.0
  P  P17  1  0.132  0.335  0.974  1.0
  P  P18  1  0.075  0.956  0.574  1.0
  P  P19  1  0.751  0.825  0.619  1.0
  P  P20  1  0.206  0.133  0.381  1.0
  P  P21  1  0.383  0.501  0.426  1.0
  P  P22  1  0.175  0.794  0.926  1.0
  P  P23  1  0.499  0.925  0.881  1.0
  P  P24  1  0.044  0.617  0.119  1.0
  P  P25  1  0.867  0.249  0.074  1.0
[/CIF]
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