The crystal structure described by Li2FeF4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one F(2), one F(3), and two equivalent F(1) atoms to form LiF4 tetrahedra that share corners with two equivalent Li(2)F4 tetrahedra, corners with four equivalent Fe(1)F4 tetrahedra, and  an edgeedge with one Li(1)F4 tetrahedra. In the second Li site, Li(2) is bonded to one F(2), one F(3), and two equivalent F(4) atoms to form LiF4 tetrahedra that share corners with two equivalent Li(1)F4 tetrahedra, corners with two equivalent Li(2)F4 tetrahedra, and corners with four equivalent Fe(1)F4 tetrahedra. Fe(1) is bonded to one F(1), one F(2), one F(3), and one F(4) atom to form FeF4 tetrahedra that share corners with four equivalent Li(1)F4 tetrahedra and corners with four equivalent Li(2)F4 tetrahedra. There are four inequivalent F sites. In the first F site, F(1) is bonded in a distorted T-shaped geometry to two equivalent Li(1) and one Fe(1) atom. In the second F site, F(2) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one Fe(1) atom. In the third F site, F(3) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one Fe(1) atom. In the fourth F site, F(4) is bonded in a trigonal planar geometry to two equivalent Li(2) and one Fe(1) atom. is represented by the CIF file [CIF]
data_Li2FeF4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.677
_cell_length_b   8.409
_cell_length_c   9.010
_cell_angle_alpha   74.330
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   414.135
_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
  Li  Li0  1  0.106  0.871  0.961  1.0
  Li  Li1  1  0.394  0.871  0.461  1.0
  Li  Li2  1  0.096  0.624  0.721  1.0
  Li  Li3  1  0.404  0.624  0.221  1.0
  Li  Li4  1  0.596  0.376  0.779  1.0
  Li  Li5  1  0.904  0.376  0.279  1.0
  Li  Li6  1  0.606  0.129  0.539  1.0
  Li  Li7  1  0.894  0.129  0.039  1.0
  Fe  Fe8  1  0.597  0.741  0.842  1.0
  Fe  Fe9  1  0.903  0.741  0.342  1.0
  Fe  Fe10  1  0.097  0.259  0.658  1.0
  Fe  Fe11  1  0.403  0.259  0.158  1.0
  F  F12  1  0.526  0.907  0.644  1.0
  F  F13  1  0.403  0.766  0.016  1.0
  F  F14  1  0.943  0.737  0.853  1.0
  F  F15  1  0.974  0.907  0.144  1.0
  F  F16  1  0.097  0.766  0.516  1.0
  F  F17  1  0.409  0.561  0.788  1.0
  F  F18  1  0.557  0.737  0.353  1.0
  F  F19  1  0.091  0.561  0.288  1.0
  F  F20  1  0.909  0.439  0.712  1.0
  F  F21  1  0.443  0.263  0.647  1.0
  F  F22  1  0.591  0.439  0.212  1.0
  F  F23  1  0.903  0.234  0.484  1.0
  F  F24  1  0.026  0.093  0.856  1.0
  F  F25  1  0.057  0.263  0.147  1.0
  F  F26  1  0.597  0.234  0.984  1.0
  F  F27  1  0.474  0.093  0.356  1.0
[/CIF]
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The crystal structure described by Li2FeF4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one F(2), one F(3), and two equivalent F(1) atoms to form LiF4 tetrahedra that share corners with two equivalent Li(2)F4 tetrahedra, corners with four equivalent Fe(1)F4 tetrahedra, and  an edgeedge with one Li(1)F4 tetrahedra. In the second Li site, Li(2) is bonded to one F(2), one F(3), and two equivalent F(4) atoms to form LiF4 tetrahedra that share corners with two equivalent Li(1)F4 tetrahedra, corners with two equivalent Li(2)F4 tetrahedra, and corners with four equivalent Fe(1)F4 tetrahedra. Fe(1) is bonded to one F(1), one F(2), one F(3), and one F(4) atom to form FeF4 tetrahedra that share corners with four equivalent Li(1)F4 tetrahedra and corners with four equivalent Li(2)F4 tetrahedra. There are four inequivalent F sites. In the first F site, F(1) is bonded in a distorted T-shaped geometry to two equivalent Li(1) and one Fe(1) atom. In the second F site, F(2) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one Fe(1) atom. In the third F site, F(3) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one Fe(1) atom. In the fourth F site, F(4) is bonded in a trigonal planar geometry to two equivalent Li(2) and one Fe(1) atom. is represented by the CIF file [CIF]
data_Li2FeF4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.677
_cell_length_b   8.409
_cell_length_c   9.010
_cell_angle_alpha   74.330
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   414.135
_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
  Li  Li0  1  0.106  0.871  0.961  1.0
  Li  Li1  1  0.394  0.871  0.461  1.0
  Li  Li2  1  0.096  0.624  0.721  1.0
  Li  Li3  1  0.404  0.624  0.221  1.0
  Li  Li4  1  0.596  0.376  0.779  1.0
  Li  Li5  1  0.904  0.376  0.279  1.0
  Li  Li6  1  0.606  0.129  0.539  1.0
  Li  Li7  1  0.894  0.129  0.039  1.0
  Fe  Fe8  1  0.597  0.741  0.842  1.0
  Fe  Fe9  1  0.903  0.741  0.342  1.0
  Fe  Fe10  1  0.097  0.259  0.658  1.0
  Fe  Fe11  1  0.403  0.259  0.158  1.0
  F  F12  1  0.526  0.907  0.644  1.0
  F  F13  1  0.403  0.766  0.016  1.0
  F  F14  1  0.943  0.737  0.853  1.0
  F  F15  1  0.974  0.907  0.144  1.0
  F  F16  1  0.097  0.766  0.516  1.0
  F  F17  1  0.409  0.561  0.788  1.0
  F  F18  1  0.557  0.737  0.353  1.0
  F  F19  1  0.091  0.561  0.288  1.0
  F  F20  1  0.909  0.439  0.712  1.0
  F  F21  1  0.443  0.263  0.647  1.0
  F  F22  1  0.591  0.439  0.212  1.0
  F  F23  1  0.903  0.234  0.484  1.0
  F  F24  1  0.026  0.093  0.856  1.0
  F  F25  1  0.057  0.263  0.147  1.0
  F  F26  1  0.597  0.234  0.984  1.0
  F  F27  1  0.474  0.093  0.356  1.0
[/CIF]
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