The material described by K2Cr2Cu(PO7)2 crystallizes in the monoclinic P2_1/c space group. K(1) is bonded in a 10-coordinate geometry to one O(1), one O(6), two equivalent O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms. Cr(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form CrO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra. Cu(1) is bonded in a distorted square co-planar geometry to two equivalent O(6) and two equivalent O(7) atoms. P(1) is bonded to one O(1), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Cr(1)O4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(6) is bonded in a distorted bent 120 degrees geometry to one K(1), one Cu(1), and one P(1) atom. In the second O site, O(7) is bonded in a bent 150 degrees geometry to one Cu(1) and one P(1) atom. In the third O site, O(1) is bonded in a distorted bent 120 degrees geometry to one K(1), one Cr(1), and one P(1) atom. In the fourth O site, O(2) is bonded in a distorted single-bond geometry to two equivalent K(1) and one Cr(1) atom. In the fifth O site, O(3) is bonded in a distorted single-bond geometry to two equivalent K(1) and one Cr(1) atom. In the sixth O site, O(4) is bonded in a single-bond geometry to two equivalent K(1) and one Cr(1) atom. In the seventh O site, O(5) is bonded in a single-bond geometry to two equivalent K(1) and one P(1) atom. is represented by the CIF file [CIF]
data_K2Cr2Cu(PO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.172
_cell_length_b   8.907
_cell_length_c   9.864
_cell_angle_alpha   88.548
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   629.947
_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  0.631  0.329  0.695  1.0
  K  K1  1  0.131  0.171  0.305  1.0
  K  K2  1  0.369  0.671  0.305  1.0
  K  K3  1  0.869  0.829  0.695  1.0
  Cr  Cr4  1  0.621  0.110  0.344  1.0
  Cr  Cr5  1  0.121  0.390  0.656  1.0
  Cr  Cr6  1  0.379  0.890  0.656  1.0
  Cr  Cr7  1  0.879  0.610  0.344  1.0
  Cu  Cu8  1  0.500  0.000  0.000  1.0
  Cu  Cu9  1  0.000  0.500  0.000  1.0
  P  P10  1  0.633  0.312  0.098  1.0
  P  P11  1  0.133  0.188  0.902  1.0
  P  P12  1  0.367  0.688  0.902  1.0
  P  P13  1  0.867  0.812  0.098  1.0
  O  O14  1  0.746  0.226  0.214  1.0
  O  O15  1  0.246  0.274  0.786  1.0
  O  O16  1  0.254  0.774  0.786  1.0
  O  O17  1  0.754  0.726  0.214  1.0
  O  O18  1  0.504  0.213  0.448  1.0
  O  O19  1  0.004  0.287  0.552  1.0
  O  O20  1  0.496  0.787  0.552  1.0
  O  O21  1  0.996  0.713  0.448  1.0
  O  O22  1  0.526  0.996  0.737  1.0
  O  O23  1  0.026  0.504  0.263  1.0
  O  O24  1  0.474  0.004  0.263  1.0
  O  O25  1  0.974  0.496  0.737  1.0
  O  O26  1  0.779  0.015  0.424  1.0
  O  O27  1  0.279  0.485  0.576  1.0
  O  O28  1  0.221  0.985  0.576  1.0
  O  O29  1  0.721  0.515  0.424  1.0
  O  O30  1  0.956  0.123  0.842  1.0
  O  O31  1  0.456  0.377  0.158  1.0
  O  O32  1  0.044  0.877  0.158  1.0
  O  O33  1  0.544  0.623  0.842  1.0
  O  O34  1  0.586  0.201  0.982  1.0
  O  O35  1  0.086  0.299  0.018  1.0
  O  O36  1  0.414  0.799  0.018  1.0
  O  O37  1  0.914  0.701  0.982  1.0
  O  O38  1  0.753  0.438  0.032  1.0
  O  O39  1  0.253  0.062  0.968  1.0
  O  O40  1  0.247  0.562  0.968  1.0
  O  O41  1  0.747  0.938  0.032  1.0
[/CIF]
.
The material described by K2Cr2Cu(PO7)2 crystallizes in the monoclinic P2_1/c space group. K(1) is bonded in a 10-coordinate geometry to one O(1), one O(6), two equivalent O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms. Cr(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form CrO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra. Cu(1) is bonded in a distorted square co-planar geometry to two equivalent O(6) and two equivalent O(7) atoms. P(1) is bonded to one O(1), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Cr(1)O4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(6) is bonded in a distorted bent 120 degrees geometry to one K(1), one Cu(1), and one P(1) atom. In the second O site, O(7) is bonded in a bent 150 degrees geometry to one Cu(1) and one P(1) atom. In the third O site, O(1) is bonded in a distorted bent 120 degrees geometry to one K(1), one Cr(1), and one P(1) atom. In the fourth O site, O(2) is bonded in a distorted single-bond geometry to two equivalent K(1) and one Cr(1) atom. In the fifth O site, O(3) is bonded in a distorted single-bond geometry to two equivalent K(1) and one Cr(1) atom. In the sixth O site, O(4) is bonded in a single-bond geometry to two equivalent K(1) and one Cr(1) atom. In the seventh O site, O(5) is bonded in a single-bond geometry to two equivalent K(1) and one P(1) atom. is represented by the CIF file [CIF]
data_K2Cr2Cu(PO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.172
_cell_length_b   8.907
_cell_length_c   9.864
_cell_angle_alpha   88.548
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   629.947
_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  0.631  0.329  0.695  1.0
  K  K1  1  0.131  0.171  0.305  1.0
  K  K2  1  0.369  0.671  0.305  1.0
  K  K3  1  0.869  0.829  0.695  1.0
  Cr  Cr4  1  0.621  0.110  0.344  1.0
  Cr  Cr5  1  0.121  0.390  0.656  1.0
  Cr  Cr6  1  0.379  0.890  0.656  1.0
  Cr  Cr7  1  0.879  0.610  0.344  1.0
  Cu  Cu8  1  0.500  0.000  0.000  1.0
  Cu  Cu9  1  0.000  0.500  0.000  1.0
  P  P10  1  0.633  0.312  0.098  1.0
  P  P11  1  0.133  0.188  0.902  1.0
  P  P12  1  0.367  0.688  0.902  1.0
  P  P13  1  0.867  0.812  0.098  1.0
  O  O14  1  0.746  0.226  0.214  1.0
  O  O15  1  0.246  0.274  0.786  1.0
  O  O16  1  0.254  0.774  0.786  1.0
  O  O17  1  0.754  0.726  0.214  1.0
  O  O18  1  0.504  0.213  0.448  1.0
  O  O19  1  0.004  0.287  0.552  1.0
  O  O20  1  0.496  0.787  0.552  1.0
  O  O21  1  0.996  0.713  0.448  1.0
  O  O22  1  0.526  0.996  0.737  1.0
  O  O23  1  0.026  0.504  0.263  1.0
  O  O24  1  0.474  0.004  0.263  1.0
  O  O25  1  0.974  0.496  0.737  1.0
  O  O26  1  0.779  0.015  0.424  1.0
  O  O27  1  0.279  0.485  0.576  1.0
  O  O28  1  0.221  0.985  0.576  1.0
  O  O29  1  0.721  0.515  0.424  1.0
  O  O30  1  0.956  0.123  0.842  1.0
  O  O31  1  0.456  0.377  0.158  1.0
  O  O32  1  0.044  0.877  0.158  1.0
  O  O33  1  0.544  0.623  0.842  1.0
  O  O34  1  0.586  0.201  0.982  1.0
  O  O35  1  0.086  0.299  0.018  1.0
  O  O36  1  0.414  0.799  0.018  1.0
  O  O37  1  0.914  0.701  0.982  1.0
  O  O38  1  0.753  0.438  0.032  1.0
  O  O39  1  0.253  0.062  0.968  1.0
  O  O40  1  0.247  0.562  0.968  1.0
  O  O41  1  0.747  0.938  0.032  1.0
[/CIF]
.