data_Cu7P
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.13
_cell_length_b   5.13
_cell_length_c   5.13
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Cu7P
_chemical_formula_sum   'Cu7 P1'
_cell_volume   95.29
_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  0.81  0.63  0.81  1.0
  Cu  Cu1  1  0.63  0.81  0.81  1.0
  Cu  Cu2  1  0.81  0.81  0.0  1.0
  Cu  Cu3  1  0.81  0.0  0.81  1.0
  Cu  Cu4  1  0.0  0.81  0.81  1.0
  Cu  Cu5  1  0.81  0.81  0.63  1.0
  Cu  Cu6  1  0.63  0.63  0.63  1.0
  P  P7  1  0.0  0.0  0.0  1.0

data_Cu7P
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.13
_cell_length_b   5.13
_cell_length_c   12.56
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Cu7P
_chemical_formula_sum   'Cu21 P3'
_cell_volume   285.88
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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  9  0.06  0.12  0.12  1.0
  Cu  Cu1  9  0.12  0.06  0.25  1.0
  Cu  Cu2  3  0.0  0.0  0.37  1.0
  P  P3  3  0.0  0.0  0.0  1.0

Cu Cu Cu Cu Cu Cu Cu P
Cu7P crystallizes in the trigonal R3m space group. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 6-coordinate geometry to one Cu(3), two equivalent Cu(1), two equivalent Cu(2), and one P(1) atom. The Cu(1)-Cu(3) bond length is 1.66 Å. Both Cu(1)-Cu(1) bond lengths are 0.96 Å. Both Cu(1)-Cu(2) bond lengths are 1.66 Å. The Cu(1)-P(1) bond length is 2.62 Å. In the second Cu site, Cu(2) is bonded in a 3-coordinate geometry to one Cu(3), two equivalent Cu(1), two equivalent Cu(2), and one P(1) atom. The Cu(2)-Cu(3) bond length is 2.62 Å. Both Cu(2)-Cu(2) bond lengths are 0.96 Å. The Cu(2)-P(1) bond length is 1.66 Å. In the third Cu site, Cu(3) is bonded in a 6-coordinate geometry to three equivalent Cu(1) and three equivalent Cu(2) atoms. P(1) is bonded in a 6-coordinate geometry to three equivalent Cu(1) and three equivalent Cu(2) atoms.