The compound described by FeCu3(PO4)4 crystallizes in the monoclinic Pm space group. Fe(1) is bonded to one O(1), one O(9), two equivalent O(11), and two equivalent O(5) atoms to form distorted FeO6 pentagonal pyramids that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent P(4)O4 tetrahedra, and  an edgeedge with one P(2)O4 tetrahedra. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a distorted rectangular see-saw-like geometry to one O(12), one O(4), and two equivalent O(2) atoms. In the second Cu site, Cu(2) is bonded in a rectangular see-saw-like geometry to one O(3), one O(7), and two equivalent O(5) atoms. In the third Cu site, Cu(3) is bonded in a rectangular see-saw-like geometry to one O(10), one O(6), and two equivalent O(8) atoms. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(10), and two equivalent O(2) atoms to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 pentagonal pyramid. In the second P site, P(2) is bonded to one O(6), one O(9), and two equivalent O(5) atoms to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 pentagonal pyramid and  an edgeedge with one Fe(1)O6 pentagonal pyramid. In the third P site, P(3) is bonded in a tetrahedral geometry to one O(4), one O(7), and two equivalent O(8) atoms. In the fourth P site, P(4) is bonded to one O(12), one O(3), and two equivalent O(11) atoms to form PO4 tetrahedra that share corners with two equivalent Fe(1)O6 pentagonal pyramids. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Cu(1) and one P(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Cu(2) and one P(4) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Cu(1) and one P(3) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Fe(1), one Cu(2), and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Cu(3) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Cu(2) and one P(3) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Cu(3) and one P(3) atom. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one Fe(1) and one P(2) atom. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to one Cu(3) and one P(1) atom. In the eleventh O site, O(11) is bonded in a bent 120 degrees geometry to one Fe(1) and one P(4) atom. In the twelfth O site, O(12) is bonded in a distorted bent 120 degrees geometry to one Cu(1) and one P(4) atom. is represented by the CIF card [CIF]
data_FeCu3(PO4)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.012
_cell_length_b   5.087
_cell_length_c   9.942
_cell_angle_alpha   87.963
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   303.870
_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
  Fe  Fe0  1  0.000  0.053  0.713  1.0
  Cu  Cu1  1  0.500  0.883  0.307  1.0
  Cu  Cu2  1  0.500  0.640  0.806  1.0
  Cu  Cu3  1  0.000  0.373  0.192  1.0
  P  P4  1  0.000  0.917  0.395  1.0
  P  P5  1  0.000  0.571  0.896  1.0
  P  P6  1  0.500  0.441  0.108  1.0
  P  P7  1  0.500  0.081  0.603  1.0
  O  O8  1  0.000  0.863  0.547  1.0
  O  O9  1  0.201  0.776  0.329  1.0
  O  O10  1  0.799  0.776  0.329  1.0
  O  O11  1  0.500  0.777  0.631  1.0
  O  O12  1  0.500  0.739  0.134  1.0
  O  O13  1  0.193  0.736  0.825  1.0
  O  O14  1  0.807  0.736  0.825  1.0
  O  O15  1  0.000  0.616  0.049  1.0
  O  O16  1  0.500  0.408  0.953  1.0
  O  O17  1  0.698  0.286  0.174  1.0
  O  O18  1  0.302  0.286  0.174  1.0
  O  O19  1  0.000  0.280  0.869  1.0
  O  O20  1  0.000  0.219  0.367  1.0
  O  O21  1  0.707  0.213  0.664  1.0
  O  O22  1  0.293  0.213  0.664  1.0
  O  O23  1  0.500  0.119  0.447  1.0
[/CIF]
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The compound described by FeCu3(PO4)4 crystallizes in the monoclinic Pm space group. Fe(1) is bonded to one O(1), one O(9), two equivalent O(11), and two equivalent O(5) atoms to form distorted FeO6 pentagonal pyramids that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent P(4)O4 tetrahedra, and  an edgeedge with one P(2)O4 tetrahedra. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a distorted rectangular see-saw-like geometry to one O(12), one O(4), and two equivalent O(2) atoms. In the second Cu site, Cu(2) is bonded in a rectangular see-saw-like geometry to one O(3), one O(7), and two equivalent O(5) atoms. In the third Cu site, Cu(3) is bonded in a rectangular see-saw-like geometry to one O(10), one O(6), and two equivalent O(8) atoms. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(10), and two equivalent O(2) atoms to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 pentagonal pyramid. In the second P site, P(2) is bonded to one O(6), one O(9), and two equivalent O(5) atoms to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 pentagonal pyramid and  an edgeedge with one Fe(1)O6 pentagonal pyramid. In the third P site, P(3) is bonded in a tetrahedral geometry to one O(4), one O(7), and two equivalent O(8) atoms. In the fourth P site, P(4) is bonded to one O(12), one O(3), and two equivalent O(11) atoms to form PO4 tetrahedra that share corners with two equivalent Fe(1)O6 pentagonal pyramids. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Cu(1) and one P(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Cu(2) and one P(4) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Cu(1) and one P(3) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Fe(1), one Cu(2), and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Cu(3) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Cu(2) and one P(3) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Cu(3) and one P(3) atom. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one Fe(1) and one P(2) atom. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to one Cu(3) and one P(1) atom. In the eleventh O site, O(11) is bonded in a bent 120 degrees geometry to one Fe(1) and one P(4) atom. In the twelfth O site, O(12) is bonded in a distorted bent 120 degrees geometry to one Cu(1) and one P(4) atom. is represented by the CIF card [CIF]
data_FeCu3(PO4)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.012
_cell_length_b   5.087
_cell_length_c   9.942
_cell_angle_alpha   87.963
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   303.870
_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
  Fe  Fe0  1  0.000  0.053  0.713  1.0
  Cu  Cu1  1  0.500  0.883  0.307  1.0
  Cu  Cu2  1  0.500  0.640  0.806  1.0
  Cu  Cu3  1  0.000  0.373  0.192  1.0
  P  P4  1  0.000  0.917  0.395  1.0
  P  P5  1  0.000  0.571  0.896  1.0
  P  P6  1  0.500  0.441  0.108  1.0
  P  P7  1  0.500  0.081  0.603  1.0
  O  O8  1  0.000  0.863  0.547  1.0
  O  O9  1  0.201  0.776  0.329  1.0
  O  O10  1  0.799  0.776  0.329  1.0
  O  O11  1  0.500  0.777  0.631  1.0
  O  O12  1  0.500  0.739  0.134  1.0
  O  O13  1  0.193  0.736  0.825  1.0
  O  O14  1  0.807  0.736  0.825  1.0
  O  O15  1  0.000  0.616  0.049  1.0
  O  O16  1  0.500  0.408  0.953  1.0
  O  O17  1  0.698  0.286  0.174  1.0
  O  O18  1  0.302  0.286  0.174  1.0
  O  O19  1  0.000  0.280  0.869  1.0
  O  O20  1  0.000  0.219  0.367  1.0
  O  O21  1  0.707  0.213  0.664  1.0
  O  O22  1  0.293  0.213  0.664  1.0
  O  O23  1  0.500  0.119  0.447  1.0
[/CIF]
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