The material structure described by CaFeP2O7 crystallizes in the triclinic P-1 space group. Ca(1) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(4), one O(6), one O(7), and two equivalent O(5) atoms. Fe(1) is bonded to one O(2), one O(3), one O(4), one O(7), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  an edgeedge with one Fe(1)O6 octahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-59°. In the second P site, P(2) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 43-56°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Ca(1), one Fe(1), and one P(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Ca(1), one Fe(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ca(1), one Fe(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Ca(1) and one P(1) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Fe(1), and one P(1) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one Ca(1), one Fe(1), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaFeP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.576
_cell_length_b   6.647
_cell_length_c   6.774
_cell_angle_alpha   86.408
_cell_angle_beta   66.609
_cell_angle_gamma   81.964
_symmetry_Int_Tables_number   1
_cell_volume   269.091
_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
  Ca  Ca0  1  0.727  0.143  0.829  1.0
  Ca  Ca1  1  0.273  0.857  0.171  1.0
  Fe  Fe2  1  0.898  0.352  0.228  1.0
  Fe  Fe3  1  0.102  0.648  0.772  1.0
  O  O4  1  0.391  0.228  0.521  1.0
  O  O5  1  0.609  0.773  0.479  1.0
  O  O6  1  0.898  0.018  0.286  1.0
  O  O7  1  0.102  0.982  0.714  1.0
  O  O8  1  0.742  0.415  0.577  1.0
  O  O9  1  0.259  0.585  0.423  1.0
  O  O10  1  0.400  0.634  0.839  1.0
  O  O11  1  0.600  0.366  0.161  1.0
  O  O12  1  0.382  0.069  0.861  1.0
  O  O13  1  0.618  0.931  0.139  1.0
  O  O14  1  0.050  0.328  0.863  1.0
  O  O15  1  0.950  0.672  0.137  1.0
  O  O16  1  0.794  0.728  0.745  1.0
  O  O17  1  0.206  0.272  0.255  1.0
  P  P18  1  0.773  0.854  0.251  1.0
  P  P19  1  0.227  0.146  0.749  1.0
  P  P20  1  0.359  0.371  0.329  1.0
  P  P21  1  0.641  0.629  0.671  1.0
[/CIF]
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The material structure described by CaFeP2O7 crystallizes in the triclinic P-1 space group. Ca(1) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(4), one O(6), one O(7), and two equivalent O(5) atoms. Fe(1) is bonded to one O(2), one O(3), one O(4), one O(7), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  an edgeedge with one Fe(1)O6 octahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-59°. In the second P site, P(2) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 43-56°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Ca(1), one Fe(1), and one P(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Ca(1), one Fe(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ca(1), one Fe(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Ca(1) and one P(1) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Fe(1), and one P(1) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one Ca(1), one Fe(1), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaFeP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.576
_cell_length_b   6.647
_cell_length_c   6.774
_cell_angle_alpha   86.408
_cell_angle_beta   66.609
_cell_angle_gamma   81.964
_symmetry_Int_Tables_number   1
_cell_volume   269.091
_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
  Ca  Ca0  1  0.727  0.143  0.829  1.0
  Ca  Ca1  1  0.273  0.857  0.171  1.0
  Fe  Fe2  1  0.898  0.352  0.228  1.0
  Fe  Fe3  1  0.102  0.648  0.772  1.0
  O  O4  1  0.391  0.228  0.521  1.0
  O  O5  1  0.609  0.773  0.479  1.0
  O  O6  1  0.898  0.018  0.286  1.0
  O  O7  1  0.102  0.982  0.714  1.0
  O  O8  1  0.742  0.415  0.577  1.0
  O  O9  1  0.259  0.585  0.423  1.0
  O  O10  1  0.400  0.634  0.839  1.0
  O  O11  1  0.600  0.366  0.161  1.0
  O  O12  1  0.382  0.069  0.861  1.0
  O  O13  1  0.618  0.931  0.139  1.0
  O  O14  1  0.050  0.328  0.863  1.0
  O  O15  1  0.950  0.672  0.137  1.0
  O  O16  1  0.794  0.728  0.745  1.0
  O  O17  1  0.206  0.272  0.255  1.0
  P  P18  1  0.773  0.854  0.251  1.0
  P  P19  1  0.227  0.146  0.749  1.0
  P  P20  1  0.359  0.371  0.329  1.0
  P  P21  1  0.641  0.629  0.671  1.0
[/CIF]
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