The crystal structure described by K2CuCPO7 crystallizes in the monoclinic P2_1/m space group. K(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(6), and two equivalent O(4) atoms to form distorted KO7 pentagonal bipyramids that share corners with two equivalent K(1)O7 pentagonal bipyramids, corners with two equivalent P(1)O4 tetrahedra,  an edgeedge with one K(1)O7 pentagonal bipyramid,  an edgeedge with one P(1)O4 tetrahedra, and  a faceface with one K(1)O7 pentagonal bipyramid. Cu(1) is bonded in a distorted rectangular see-saw-like geometry to one O(2), one O(3), one O(5), and one O(6) atom. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. P(1) is bonded to one O(5), one O(6), and two equivalent O(4) atoms to form PO4 tetrahedra that share corners with four equivalent K(1)O7 pentagonal bipyramids and edges with two equivalent K(1)O7 pentagonal bipyramids. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent K(1) and one C(1) atom. In the second O site, O(2) is bonded to two equivalent K(1), one Cu(1), and one C(1) atom to form distorted edge-sharing OK2CuC trigonal pyramids. In the third O site, O(3) is bonded to two equivalent K(1), one Cu(1), and one C(1) atom to form distorted edge-sharing OK2CuC trigonal pyramids. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to two equivalent K(1) and one P(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to two equivalent K(1), one Cu(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to two equivalent K(1), one Cu(1), and one P(1) atom. is represented by the CIF file [CIF]
data_K2CuPCO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.843
_cell_length_b   5.241
_cell_length_c   9.244
_cell_angle_alpha   89.992
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   379.984
_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
  K  K0  1  0.022  0.243  0.746  1.0
  K  K1  1  0.478  0.243  0.746  1.0
  K  K2  1  0.522  0.757  0.254  1.0
  K  K3  1  0.978  0.757  0.254  1.0
  Cu  Cu4  1  0.750  0.773  0.645  1.0
  Cu  Cu5  1  0.250  0.227  0.355  1.0
  P  P6  1  0.250  0.716  0.575  1.0
  P  P7  1  0.750  0.284  0.425  1.0
  C  C8  1  0.750  0.728  0.902  1.0
  C  C9  1  0.250  0.272  0.098  1.0
  O  O10  1  0.250  0.284  0.963  1.0
  O  O11  1  0.750  0.942  0.829  1.0
  O  O12  1  0.750  0.534  0.813  1.0
  O  O13  1  0.087  0.755  0.663  1.0
  O  O14  1  0.413  0.755  0.663  1.0
  O  O15  1  0.750  0.119  0.568  1.0
  O  O16  1  0.250  0.424  0.522  1.0
  O  O17  1  0.750  0.576  0.478  1.0
  O  O18  1  0.250  0.881  0.432  1.0
  O  O19  1  0.587  0.245  0.337  1.0
  O  O20  1  0.913  0.245  0.337  1.0
  O  O21  1  0.250  0.466  0.187  1.0
  O  O22  1  0.250  0.058  0.171  1.0
  O  O23  1  0.750  0.716  0.037  1.0
[/CIF]
.
The crystal structure described by K2CuCPO7 crystallizes in the monoclinic P2_1/m space group. K(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(6), and two equivalent O(4) atoms to form distorted KO7 pentagonal bipyramids that share corners with two equivalent K(1)O7 pentagonal bipyramids, corners with two equivalent P(1)O4 tetrahedra,  an edgeedge with one K(1)O7 pentagonal bipyramid,  an edgeedge with one P(1)O4 tetrahedra, and  a faceface with one K(1)O7 pentagonal bipyramid. Cu(1) is bonded in a distorted rectangular see-saw-like geometry to one O(2), one O(3), one O(5), and one O(6) atom. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. P(1) is bonded to one O(5), one O(6), and two equivalent O(4) atoms to form PO4 tetrahedra that share corners with four equivalent K(1)O7 pentagonal bipyramids and edges with two equivalent K(1)O7 pentagonal bipyramids. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent K(1) and one C(1) atom. In the second O site, O(2) is bonded to two equivalent K(1), one Cu(1), and one C(1) atom to form distorted edge-sharing OK2CuC trigonal pyramids. In the third O site, O(3) is bonded to two equivalent K(1), one Cu(1), and one C(1) atom to form distorted edge-sharing OK2CuC trigonal pyramids. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to two equivalent K(1) and one P(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to two equivalent K(1), one Cu(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to two equivalent K(1), one Cu(1), and one P(1) atom. is represented by the CIF file [CIF]
data_K2CuPCO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.843
_cell_length_b   5.241
_cell_length_c   9.244
_cell_angle_alpha   89.992
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   379.984
_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
  K  K0  1  0.022  0.243  0.746  1.0
  K  K1  1  0.478  0.243  0.746  1.0
  K  K2  1  0.522  0.757  0.254  1.0
  K  K3  1  0.978  0.757  0.254  1.0
  Cu  Cu4  1  0.750  0.773  0.645  1.0
  Cu  Cu5  1  0.250  0.227  0.355  1.0
  P  P6  1  0.250  0.716  0.575  1.0
  P  P7  1  0.750  0.284  0.425  1.0
  C  C8  1  0.750  0.728  0.902  1.0
  C  C9  1  0.250  0.272  0.098  1.0
  O  O10  1  0.250  0.284  0.963  1.0
  O  O11  1  0.750  0.942  0.829  1.0
  O  O12  1  0.750  0.534  0.813  1.0
  O  O13  1  0.087  0.755  0.663  1.0
  O  O14  1  0.413  0.755  0.663  1.0
  O  O15  1  0.750  0.119  0.568  1.0
  O  O16  1  0.250  0.424  0.522  1.0
  O  O17  1  0.750  0.576  0.478  1.0
  O  O18  1  0.250  0.881  0.432  1.0
  O  O19  1  0.587  0.245  0.337  1.0
  O  O20  1  0.913  0.245  0.337  1.0
  O  O21  1  0.250  0.466  0.187  1.0
  O  O22  1  0.250  0.058  0.171  1.0
  O  O23  1  0.750  0.716  0.037  1.0
[/CIF]
.