The compound described by LiFeP2O7 crystallizes in the triclinic P1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a distorted rectangular see-saw-like geometry to one O(11), one O(14), one O(5), and one O(9) atom. In the second Li site, Li(2) is bonded in a distorted rectangular see-saw-like geometry to one O(10), one O(13), one O(3), and one O(4) atom. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(13), one O(2), one O(3), and one O(7) atom to form FeO5 trigonal bipyramids that share  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(3)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(12), one O(5), one O(6), one O(8), and one O(9) atom to form FeO5 trigonal bipyramids that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and corners with two equivalent P(4)O4 tetrahedra. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(14), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one Fe(2)O5 trigonal bipyramid, and corners with two equivalent Fe(1)O5 trigonal bipyramids. In the second P site, P(2) is bonded to one O(11), one O(12), one O(13), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one Fe(1)O5 trigonal bipyramid, and corners with two equivalent Fe(2)O5 trigonal bipyramids. In the third P site, P(3) is bonded to one O(3), one O(4), one O(5), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one Fe(2)O5 trigonal bipyramid, and corners with two equivalent Fe(1)O5 trigonal bipyramids. In the fourth P site, P(4) is bonded to one O(10), one O(12), one O(2), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one Fe(1)O5 trigonal bipyramid, and corners with two equivalent Fe(2)O5 trigonal bipyramids. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(4) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Li(2), one Fe(1), and one P(3) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Li(2) and one P(3) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one Fe(2), and one P(3) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Fe(2) and one P(1) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Fe(1), one P(1), and one P(3) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Fe(2) and one P(4) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Li(1), one Fe(2), and one P(2) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Li(2) and one P(4) atom. In the eleventh O site, O(11) is bonded in a distorted bent 150 degrees geometry to one Li(1) and one P(2) atom. In the twelfth O site, O(12) is bonded in a trigonal planar geometry to one Fe(2), one P(2), and one P(4) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal planar geometry to one Li(2), one Fe(1), and one P(2) atom. In the fourteenth O site, O(14) is bonded in a bent 150 degrees geometry to one Li(1) and one P(1) atom. is represented by the CIF file [CIF]
data_LiFeP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.814
_cell_length_b   8.035
_cell_length_c   8.707
_cell_angle_alpha   107.543
_cell_angle_beta   90.305
_cell_angle_gamma   107.043
_symmetry_Int_Tables_number   1
_cell_volume   305.388
_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
  Li  Li0  1  0.130  0.095  0.448  1.0
  Li  Li1  1  0.462  0.092  0.950  1.0
  Fe  Fe2  1  0.623  0.512  0.052  1.0
  Fe  Fe3  1  0.390  0.515  0.553  1.0
  P  P4  1  0.229  0.706  0.297  1.0
  P  P5  1  0.771  0.300  0.691  1.0
  P  P6  1  0.035  0.303  0.189  1.0
  P  P7  1  0.973  0.702  0.794  1.0
  O  O8  1  0.450  0.692  0.171  1.0
  O  O9  1  0.819  0.681  0.944  1.0
  O  O10  1  0.286  0.314  0.078  1.0
  O  O11  1  0.760  0.152  0.119  1.0
  O  O12  1  0.152  0.317  0.359  1.0
  O  O13  1  0.339  0.687  0.454  1.0
  O  O14  1  0.952  0.502  0.213  1.0
  O  O15  1  0.755  0.692  0.660  1.0
  O  O16  1  0.528  0.315  0.583  1.0
  O  O17  1  0.257  0.849  0.826  1.0
  O  O18  1  0.894  0.149  0.619  1.0
  O  O19  1  0.052  0.499  0.716  1.0
  O  O20  1  0.672  0.312  0.862  1.0
  O  O21  1  0.094  0.854  0.316  1.0
[/CIF]
.
The compound described by LiFeP2O7 crystallizes in the triclinic P1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a distorted rectangular see-saw-like geometry to one O(11), one O(14), one O(5), and one O(9) atom. In the second Li site, Li(2) is bonded in a distorted rectangular see-saw-like geometry to one O(10), one O(13), one O(3), and one O(4) atom. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(13), one O(2), one O(3), and one O(7) atom to form FeO5 trigonal bipyramids that share  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(3)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(12), one O(5), one O(6), one O(8), and one O(9) atom to form FeO5 trigonal bipyramids that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and corners with two equivalent P(4)O4 tetrahedra. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(14), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one Fe(2)O5 trigonal bipyramid, and corners with two equivalent Fe(1)O5 trigonal bipyramids. In the second P site, P(2) is bonded to one O(11), one O(12), one O(13), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one Fe(1)O5 trigonal bipyramid, and corners with two equivalent Fe(2)O5 trigonal bipyramids. In the third P site, P(3) is bonded to one O(3), one O(4), one O(5), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one Fe(2)O5 trigonal bipyramid, and corners with two equivalent Fe(1)O5 trigonal bipyramids. In the fourth P site, P(4) is bonded to one O(10), one O(12), one O(2), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one Fe(1)O5 trigonal bipyramid, and corners with two equivalent Fe(2)O5 trigonal bipyramids. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(4) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Li(2), one Fe(1), and one P(3) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Li(2) and one P(3) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one Fe(2), and one P(3) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Fe(2) and one P(1) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Fe(1), one P(1), and one P(3) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Fe(2) and one P(4) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Li(1), one Fe(2), and one P(2) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Li(2) and one P(4) atom. In the eleventh O site, O(11) is bonded in a distorted bent 150 degrees geometry to one Li(1) and one P(2) atom. In the twelfth O site, O(12) is bonded in a trigonal planar geometry to one Fe(2), one P(2), and one P(4) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal planar geometry to one Li(2), one Fe(1), and one P(2) atom. In the fourteenth O site, O(14) is bonded in a bent 150 degrees geometry to one Li(1) and one P(1) atom. is represented by the CIF file [CIF]
data_LiFeP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.814
_cell_length_b   8.035
_cell_length_c   8.707
_cell_angle_alpha   107.543
_cell_angle_beta   90.305
_cell_angle_gamma   107.043
_symmetry_Int_Tables_number   1
_cell_volume   305.388
_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
  Li  Li0  1  0.130  0.095  0.448  1.0
  Li  Li1  1  0.462  0.092  0.950  1.0
  Fe  Fe2  1  0.623  0.512  0.052  1.0
  Fe  Fe3  1  0.390  0.515  0.553  1.0
  P  P4  1  0.229  0.706  0.297  1.0
  P  P5  1  0.771  0.300  0.691  1.0
  P  P6  1  0.035  0.303  0.189  1.0
  P  P7  1  0.973  0.702  0.794  1.0
  O  O8  1  0.450  0.692  0.171  1.0
  O  O9  1  0.819  0.681  0.944  1.0
  O  O10  1  0.286  0.314  0.078  1.0
  O  O11  1  0.760  0.152  0.119  1.0
  O  O12  1  0.152  0.317  0.359  1.0
  O  O13  1  0.339  0.687  0.454  1.0
  O  O14  1  0.952  0.502  0.213  1.0
  O  O15  1  0.755  0.692  0.660  1.0
  O  O16  1  0.528  0.315  0.583  1.0
  O  O17  1  0.257  0.849  0.826  1.0
  O  O18  1  0.894  0.149  0.619  1.0
  O  O19  1  0.052  0.499  0.716  1.0
  O  O20  1  0.672  0.312  0.862  1.0
  O  O21  1  0.094  0.854  0.316  1.0
[/CIF]
.