The material described by Li2Cr2O7 crystallizes in the triclinic P-1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(7), and two equivalent O(5) atoms. In the second Li site, Li(2) is bonded in a distorted see-saw-like geometry to one O(2), one O(4), one O(6), and one O(7) atom. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(2), one O(3), and one O(7) atom to form corner-sharing CrO4 tetrahedra. In the second Cr site, Cr(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form corner-sharing CrO4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Li(1) and one Cr(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Li(1), one Li(2), and one Cr(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Li(2) and one Cr(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to two equivalent Li(1) and one Cr(2) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Li(2) and one Cr(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Li(1), one Li(2), and one Cr(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2Cr2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.563
_cell_length_b   6.764
_cell_length_c   7.109
_cell_angle_alpha   112.140
_cell_angle_beta   89.790
_cell_angle_gamma   96.797
_symmetry_Int_Tables_number   1
_cell_volume   289.962
_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  0.373  0.703  0.646  1.0
  Li  Li1  1  0.186  0.891  0.263  1.0
  Li  Li2  1  0.814  0.109  0.737  1.0
  Li  Li3  1  0.627  0.297  0.354  1.0
  Cr  Cr4  1  0.892  0.660  0.815  1.0
  Cr  Cr5  1  0.340  0.236  0.747  1.0
  Cr  Cr6  1  0.660  0.764  0.253  1.0
  Cr  Cr7  1  0.108  0.340  0.185  1.0
  O  O8  1  0.132  0.764  0.830  1.0
  O  O9  1  0.743  0.810  0.759  1.0
  O  O10  1  0.165  0.343  0.939  1.0
  O  O11  1  0.777  0.978  0.434  1.0
  O  O12  1  0.422  0.416  0.652  1.0
  O  O13  1  0.536  0.167  0.838  1.0
  O  O14  1  0.857  0.414  0.646  1.0
  O  O15  1  0.143  0.586  0.354  1.0
  O  O16  1  0.464  0.833  0.162  1.0
  O  O17  1  0.578  0.584  0.348  1.0
  O  O18  1  0.223  0.022  0.566  1.0
  O  O19  1  0.835  0.657  0.061  1.0
  O  O20  1  0.257  0.190  0.241  1.0
  O  O21  1  0.868  0.236  0.170  1.0
[/CIF]
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The material described by Li2Cr2O7 crystallizes in the triclinic P-1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(7), and two equivalent O(5) atoms. In the second Li site, Li(2) is bonded in a distorted see-saw-like geometry to one O(2), one O(4), one O(6), and one O(7) atom. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(2), one O(3), and one O(7) atom to form corner-sharing CrO4 tetrahedra. In the second Cr site, Cr(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form corner-sharing CrO4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Li(1) and one Cr(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Li(1), one Li(2), and one Cr(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Li(2) and one Cr(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to two equivalent Li(1) and one Cr(2) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Li(2) and one Cr(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Li(1), one Li(2), and one Cr(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2Cr2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.563
_cell_length_b   6.764
_cell_length_c   7.109
_cell_angle_alpha   112.140
_cell_angle_beta   89.790
_cell_angle_gamma   96.797
_symmetry_Int_Tables_number   1
_cell_volume   289.962
_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  0.373  0.703  0.646  1.0
  Li  Li1  1  0.186  0.891  0.263  1.0
  Li  Li2  1  0.814  0.109  0.737  1.0
  Li  Li3  1  0.627  0.297  0.354  1.0
  Cr  Cr4  1  0.892  0.660  0.815  1.0
  Cr  Cr5  1  0.340  0.236  0.747  1.0
  Cr  Cr6  1  0.660  0.764  0.253  1.0
  Cr  Cr7  1  0.108  0.340  0.185  1.0
  O  O8  1  0.132  0.764  0.830  1.0
  O  O9  1  0.743  0.810  0.759  1.0
  O  O10  1  0.165  0.343  0.939  1.0
  O  O11  1  0.777  0.978  0.434  1.0
  O  O12  1  0.422  0.416  0.652  1.0
  O  O13  1  0.536  0.167  0.838  1.0
  O  O14  1  0.857  0.414  0.646  1.0
  O  O15  1  0.143  0.586  0.354  1.0
  O  O16  1  0.464  0.833  0.162  1.0
  O  O17  1  0.578  0.584  0.348  1.0
  O  O18  1  0.223  0.022  0.566  1.0
  O  O19  1  0.835  0.657  0.061  1.0
  O  O20  1  0.257  0.190  0.241  1.0
  O  O21  1  0.868  0.236  0.170  1.0
[/CIF]
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