The material described by KCuFe(PO4)2 crystallizes in the monoclinic P2_1/c space group. K(1) is bonded in a 9-coordinate geometry to one O(2), one O(4), one O(5), one O(6), one O(8), two equivalent O(1), and two equivalent O(7) atoms. Fe(1) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form FeO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and corners with two equivalent Cu(1)O5 trigonal bipyramids. Cu(1) is bonded to one O(1), one O(2), one O(3), and two equivalent O(8) atoms to form distorted CuO5 trigonal bipyramids that share corners with two equivalent Fe(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  an edgeedge with one P(1)O4 tetrahedra, and  an edgeedge with one Cu(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 51-61°. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra,  a cornercorner with one Cu(1)O5 trigonal bipyramid, and  an edgeedge with one Cu(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 38-43°. In the second P site, P(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra and corners with two equivalent Cu(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 38-41°. There are eight inequivalent O sites. In the first O site, O(4) is bonded in a distorted bent 150 degrees geometry to one K(1), one Fe(1), and one P(1) atom. In the second O site, O(5) is bonded in a distorted bent 150 degrees geometry to one K(1), one Fe(1), and one P(2) atom. In the third O site, O(6) is bonded in a 3-coordinate geometry to one K(1), one Fe(1), and one P(2) atom. In the fourth O site, O(7) is bonded in a 2-coordinate geometry to two equivalent K(1), one Fe(1), and one P(2) atom. In the fifth O site, O(8) is bonded in a 3-coordinate geometry to one K(1), two equivalent Cu(1), and one P(2) atom. In the sixth O site, O(1) is bonded in a distorted bent 120 degrees geometry to two equivalent K(1), one Cu(1), and one P(1) atom. In the seventh O site, O(2) is bonded in a 3-coordinate geometry to one K(1), one Fe(1), one Cu(1), and one P(1) atom. In the eighth O site, O(3) is bonded in a 3-coordinate geometry to one Fe(1), one Cu(1), and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KFeCu(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.056
_cell_length_b   8.101
_cell_length_c   9.207
_cell_angle_alpha   63.556
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   671.542
_cell_formula_units_Z   4
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  0.366  0.658  0.425  1.0
  K  K1  1  0.134  0.658  0.925  1.0
  K  K2  1  0.634  0.342  0.575  1.0
  K  K3  1  0.866  0.342  0.075  1.0
  Fe  Fe4  1  0.626  0.729  0.757  1.0
  Fe  Fe5  1  0.874  0.729  0.257  1.0
  Fe  Fe6  1  0.374  0.272  0.243  1.0
  Fe  Fe7  1  0.126  0.272  0.743  1.0
  Cu  Cu8  1  0.620  0.080  0.053  1.0
  Cu  Cu9  1  0.880  0.080  0.553  1.0
  Cu  Cu10  1  0.380  0.920  0.947  1.0
  Cu  Cu11  1  0.120  0.920  0.447  1.0
  P  P12  1  0.660  0.012  0.359  1.0
  P  P13  1  0.840  0.012  0.859  1.0
  P  P14  1  0.340  0.988  0.641  1.0
  P  P15  1  0.160  0.988  0.141  1.0
  P  P16  1  0.413  0.381  0.852  1.0
  P  P17  1  0.087  0.381  0.352  1.0
  P  P18  1  0.587  0.619  0.148  1.0
  P  P19  1  0.913  0.619  0.648  1.0
  O  O20  1  0.764  0.157  0.893  1.0
  O  O21  1  0.736  0.157  0.393  1.0
  O  O22  1  0.236  0.843  0.107  1.0
  O  O23  1  0.264  0.843  0.607  1.0
  O  O24  1  0.747  0.957  0.244  1.0
  O  O25  1  0.753  0.957  0.744  1.0
  O  O26  1  0.253  0.043  0.756  1.0
  O  O27  1  0.247  0.043  0.256  1.0
  O  O28  1  0.538  0.109  0.244  1.0
  O  O29  1  0.962  0.109  0.744  1.0
  O  O30  1  0.462  0.891  0.756  1.0
  O  O31  1  0.038  0.891  0.256  1.0
  O  O32  1  0.614  0.845  0.512  1.0
  O  O33  1  0.886  0.845  0.012  1.0
  O  O34  1  0.386  0.155  0.488  1.0
  O  O35  1  0.114  0.155  0.988  1.0
  O  O36  1  0.368  0.399  0.004  1.0
  O  O37  1  0.132  0.399  0.504  1.0
  O  O38  1  0.632  0.601  0.996  1.0
  O  O39  1  0.868  0.601  0.496  1.0
  O  O40  1  0.292  0.402  0.740  1.0
  O  O41  1  0.208  0.402  0.240  1.0
  O  O42  1  0.708  0.598  0.260  1.0
  O  O43  1  0.792  0.598  0.760  1.0
  O  O44  1  0.513  0.531  0.747  1.0
  O  O45  1  0.987  0.531  0.247  1.0
  O  O46  1  0.487  0.469  0.253  1.0
  O  O47  1  0.013  0.469  0.753  1.0
  O  O48  1  0.477  0.187  0.898  1.0
  O  O49  1  0.023  0.187  0.398  1.0
  O  O50  1  0.523  0.813  0.102  1.0
  O  O51  1  0.977  0.813  0.602  1.0
[/CIF]
.
The material described by KCuFe(PO4)2 crystallizes in the monoclinic P2_1/c space group. K(1) is bonded in a 9-coordinate geometry to one O(2), one O(4), one O(5), one O(6), one O(8), two equivalent O(1), and two equivalent O(7) atoms. Fe(1) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form FeO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and corners with two equivalent Cu(1)O5 trigonal bipyramids. Cu(1) is bonded to one O(1), one O(2), one O(3), and two equivalent O(8) atoms to form distorted CuO5 trigonal bipyramids that share corners with two equivalent Fe(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  an edgeedge with one P(1)O4 tetrahedra, and  an edgeedge with one Cu(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 51-61°. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra,  a cornercorner with one Cu(1)O5 trigonal bipyramid, and  an edgeedge with one Cu(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 38-43°. In the second P site, P(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra and corners with two equivalent Cu(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 38-41°. There are eight inequivalent O sites. In the first O site, O(4) is bonded in a distorted bent 150 degrees geometry to one K(1), one Fe(1), and one P(1) atom. In the second O site, O(5) is bonded in a distorted bent 150 degrees geometry to one K(1), one Fe(1), and one P(2) atom. In the third O site, O(6) is bonded in a 3-coordinate geometry to one K(1), one Fe(1), and one P(2) atom. In the fourth O site, O(7) is bonded in a 2-coordinate geometry to two equivalent K(1), one Fe(1), and one P(2) atom. In the fifth O site, O(8) is bonded in a 3-coordinate geometry to one K(1), two equivalent Cu(1), and one P(2) atom. In the sixth O site, O(1) is bonded in a distorted bent 120 degrees geometry to two equivalent K(1), one Cu(1), and one P(1) atom. In the seventh O site, O(2) is bonded in a 3-coordinate geometry to one K(1), one Fe(1), one Cu(1), and one P(1) atom. In the eighth O site, O(3) is bonded in a 3-coordinate geometry to one Fe(1), one Cu(1), and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KFeCu(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.056
_cell_length_b   8.101
_cell_length_c   9.207
_cell_angle_alpha   63.556
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   671.542
_cell_formula_units_Z   4
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  0.366  0.658  0.425  1.0
  K  K1  1  0.134  0.658  0.925  1.0
  K  K2  1  0.634  0.342  0.575  1.0
  K  K3  1  0.866  0.342  0.075  1.0
  Fe  Fe4  1  0.626  0.729  0.757  1.0
  Fe  Fe5  1  0.874  0.729  0.257  1.0
  Fe  Fe6  1  0.374  0.272  0.243  1.0
  Fe  Fe7  1  0.126  0.272  0.743  1.0
  Cu  Cu8  1  0.620  0.080  0.053  1.0
  Cu  Cu9  1  0.880  0.080  0.553  1.0
  Cu  Cu10  1  0.380  0.920  0.947  1.0
  Cu  Cu11  1  0.120  0.920  0.447  1.0
  P  P12  1  0.660  0.012  0.359  1.0
  P  P13  1  0.840  0.012  0.859  1.0
  P  P14  1  0.340  0.988  0.641  1.0
  P  P15  1  0.160  0.988  0.141  1.0
  P  P16  1  0.413  0.381  0.852  1.0
  P  P17  1  0.087  0.381  0.352  1.0
  P  P18  1  0.587  0.619  0.148  1.0
  P  P19  1  0.913  0.619  0.648  1.0
  O  O20  1  0.764  0.157  0.893  1.0
  O  O21  1  0.736  0.157  0.393  1.0
  O  O22  1  0.236  0.843  0.107  1.0
  O  O23  1  0.264  0.843  0.607  1.0
  O  O24  1  0.747  0.957  0.244  1.0
  O  O25  1  0.753  0.957  0.744  1.0
  O  O26  1  0.253  0.043  0.756  1.0
  O  O27  1  0.247  0.043  0.256  1.0
  O  O28  1  0.538  0.109  0.244  1.0
  O  O29  1  0.962  0.109  0.744  1.0
  O  O30  1  0.462  0.891  0.756  1.0
  O  O31  1  0.038  0.891  0.256  1.0
  O  O32  1  0.614  0.845  0.512  1.0
  O  O33  1  0.886  0.845  0.012  1.0
  O  O34  1  0.386  0.155  0.488  1.0
  O  O35  1  0.114  0.155  0.988  1.0
  O  O36  1  0.368  0.399  0.004  1.0
  O  O37  1  0.132  0.399  0.504  1.0
  O  O38  1  0.632  0.601  0.996  1.0
  O  O39  1  0.868  0.601  0.496  1.0
  O  O40  1  0.292  0.402  0.740  1.0
  O  O41  1  0.208  0.402  0.240  1.0
  O  O42  1  0.708  0.598  0.260  1.0
  O  O43  1  0.792  0.598  0.760  1.0
  O  O44  1  0.513  0.531  0.747  1.0
  O  O45  1  0.987  0.531  0.247  1.0
  O  O46  1  0.487  0.469  0.253  1.0
  O  O47  1  0.013  0.469  0.753  1.0
  O  O48  1  0.477  0.187  0.898  1.0
  O  O49  1  0.023  0.187  0.398  1.0
  O  O50  1  0.523  0.813  0.102  1.0
  O  O51  1  0.977  0.813  0.602  1.0
[/CIF]
.