The compound described by Li2VFe(P2O7)2 crystallizes in the triclinic P1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a see-saw-like geometry to one O(11), one O(2), one O(3), and one O(5) atom. In the second Li site, Li(2) is bonded in a see-saw-like geometry to one O(10), one O(12), one O(13), and one O(4) atom. V(1) is bonded to one O(1), one O(12), one O(2), one O(4), one O(5), and one O(6) atom to form VO6 octahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and corners with two equivalent P(4)O4 tetrahedra. Fe(1) is bonded to one O(10), one O(11), one O(13), one O(14), one O(3), and one O(9) atom to form FeO6 octahedra that share  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(10), one O(3), one O(4), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one V(1)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 45-49°. In the second P site, P(2) is bonded to one O(14), one O(2), one O(8), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one V(1)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and  a cornercorner with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-48°. In the third P site, P(3) is bonded to one O(1), one O(13), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra, corners with two equivalent V(1)O6 octahedra, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-50°. In the fourth P site, P(4) is bonded to one O(11), one O(12), one O(5), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra, corners with two equivalent V(1)O6 octahedra, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 45-50°. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one V(1) and one P(3) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Li(1), one V(1), and one P(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Li(1), one Fe(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Li(2), one V(1), and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one V(1), and one P(4) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one V(1) and one P(3) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one P(1) and one P(3) atom. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to one P(2) and one P(4) atom. In the ninth O site, O(9) is bonded in a distorted bent 120 degrees geometry to one Fe(1) and one P(2) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Li(2), one Fe(1), and one P(1) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal planar geometry to one Li(1), one Fe(1), and one P(4) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Li(2), one V(1), and one P(4) atom. In the thirteenth O site, O(13) is bonded in a distorted T-shaped geometry to one Li(2), one Fe(1), and one P(3) atom. In the fourteenth O site, O(14) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(2) atom. is represented by the CIF file [CIF]
data_Li2VFe(P2O7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.897
_cell_length_b   7.041
_cell_length_c   8.261
_cell_angle_alpha   89.644
_cell_angle_beta   89.764
_cell_angle_gamma   71.328
_symmetry_Int_Tables_number   1
_cell_volume   269.842
_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  0.215  0.267  1.000  1.0
  Li  Li1  1  0.822  0.670  0.861  1.0
  Li  Li2  1  0.179  0.329  0.361  1.0
  O  O3  1  0.952  0.854  0.324  1.0
  O  O4  1  0.861  0.885  0.698  1.0
  O  O5  1  0.813  0.482  0.038  1.0
  O  O6  1  0.754  0.508  0.343  1.0
  O  O7  1  0.599  0.606  0.678  1.0
  O  O8  1  0.401  0.918  0.432  1.0
  O  O9  1  0.406  0.754  0.152  1.0
  O  O10  1  0.596  0.247  0.653  1.0
  O  O11  1  0.596  0.087  0.934  1.0
  O  O12  1  0.399  0.395  0.179  1.0
  O  O13  1  0.247  0.490  0.846  1.0
  O  O14  1  0.185  0.517  0.540  1.0
  O  O15  1  0.137  0.116  0.194  1.0
  O  O16  1  0.049  0.144  0.827  1.0
  P  P17  1  0.601  0.522  0.180  1.0
  P  P18  1  0.785  0.086  0.785  1.0
  P  P19  1  0.217  0.914  0.283  1.0
  P  P20  1  0.399  0.477  0.681  1.0
  V  V21  1  0.785  0.729  0.499  1.0
[/CIF]
.
The compound described by Li2VFe(P2O7)2 crystallizes in the triclinic P1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a see-saw-like geometry to one O(11), one O(2), one O(3), and one O(5) atom. In the second Li site, Li(2) is bonded in a see-saw-like geometry to one O(10), one O(12), one O(13), and one O(4) atom. V(1) is bonded to one O(1), one O(12), one O(2), one O(4), one O(5), and one O(6) atom to form VO6 octahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and corners with two equivalent P(4)O4 tetrahedra. Fe(1) is bonded to one O(10), one O(11), one O(13), one O(14), one O(3), and one O(9) atom to form FeO6 octahedra that share  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(10), one O(3), one O(4), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one V(1)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 45-49°. In the second P site, P(2) is bonded to one O(14), one O(2), one O(8), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one V(1)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and  a cornercorner with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-48°. In the third P site, P(3) is bonded to one O(1), one O(13), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra, corners with two equivalent V(1)O6 octahedra, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-50°. In the fourth P site, P(4) is bonded to one O(11), one O(12), one O(5), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra, corners with two equivalent V(1)O6 octahedra, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 45-50°. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one V(1) and one P(3) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Li(1), one V(1), and one P(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Li(1), one Fe(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Li(2), one V(1), and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one V(1), and one P(4) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one V(1) and one P(3) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one P(1) and one P(3) atom. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to one P(2) and one P(4) atom. In the ninth O site, O(9) is bonded in a distorted bent 120 degrees geometry to one Fe(1) and one P(2) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Li(2), one Fe(1), and one P(1) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal planar geometry to one Li(1), one Fe(1), and one P(4) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Li(2), one V(1), and one P(4) atom. In the thirteenth O site, O(13) is bonded in a distorted T-shaped geometry to one Li(2), one Fe(1), and one P(3) atom. In the fourteenth O site, O(14) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(2) atom. is represented by the CIF file [CIF]
data_Li2VFe(P2O7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.897
_cell_length_b   7.041
_cell_length_c   8.261
_cell_angle_alpha   89.644
_cell_angle_beta   89.764
_cell_angle_gamma   71.328
_symmetry_Int_Tables_number   1
_cell_volume   269.842
_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  0.215  0.267  1.000  1.0
  Li  Li1  1  0.822  0.670  0.861  1.0
  Li  Li2  1  0.179  0.329  0.361  1.0
  O  O3  1  0.952  0.854  0.324  1.0
  O  O4  1  0.861  0.885  0.698  1.0
  O  O5  1  0.813  0.482  0.038  1.0
  O  O6  1  0.754  0.508  0.343  1.0
  O  O7  1  0.599  0.606  0.678  1.0
  O  O8  1  0.401  0.918  0.432  1.0
  O  O9  1  0.406  0.754  0.152  1.0
  O  O10  1  0.596  0.247  0.653  1.0
  O  O11  1  0.596  0.087  0.934  1.0
  O  O12  1  0.399  0.395  0.179  1.0
  O  O13  1  0.247  0.490  0.846  1.0
  O  O14  1  0.185  0.517  0.540  1.0
  O  O15  1  0.137  0.116  0.194  1.0
  O  O16  1  0.049  0.144  0.827  1.0
  P  P17  1  0.601  0.522  0.180  1.0
  P  P18  1  0.785  0.086  0.785  1.0
  P  P19  1  0.217  0.914  0.283  1.0
  P  P20  1  0.399  0.477  0.681  1.0
  V  V21  1  0.785  0.729  0.499  1.0
[/CIF]
.