The compound 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 6-coordinate geometry to one O(1), one O(4), one O(5), one O(7), and two equivalent O(3) atoms. In the second Li site, Li(2) is bonded to one O(1), one O(2), one O(5), one O(7), and two equivalent O(6) atoms to form distorted LiO6 pentagonal pyramids that share corners with three equivalent Cr(1)O4 tetrahedra, corners with three equivalent Cr(2)O4 tetrahedra, and  an edgeedge with one Li(2)O6 pentagonal pyramid. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form CrO4 tetrahedra that share corners with three equivalent Li(2)O6 pentagonal pyramids and  a cornercorner with one Cr(2)O4 tetrahedra. In the second Cr site, Cr(2) is bonded to one O(3), one O(4), one O(6), and one O(7) atom to form CrO4 tetrahedra that share corners with three equivalent Li(2)O6 pentagonal pyramids and  a cornercorner with one Cr(1)O4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Li(1), one Li(2), and one Cr(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Li(2) and one Cr(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Li(1) and one Cr(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Li(1), one Cr(1), and one Cr(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one Li(2), and one Cr(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to two equivalent 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(2) atom. is represented by the CIF card [CIF]
data_Li2Cr2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.469
_cell_length_b   6.735
_cell_length_c   6.763
_cell_angle_alpha   93.263
_cell_angle_beta   111.021
_cell_angle_gamma   93.369
_symmetry_Int_Tables_number   1
_cell_volume   273.616
_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  0.747  0.168  0.175  1.0
  Li  Li1  1  0.288  0.374  0.547  1.0
  Li  Li2  1  0.712  0.626  0.453  1.0
  Li  Li3  1  0.253  0.832  0.825  1.0
  Cr  Cr4  1  0.795  0.155  0.678  1.0
  Cr  Cr5  1  0.244  0.335  0.022  1.0
  Cr  Cr6  1  0.756  0.665  0.978  1.0
  Cr  Cr7  1  0.205  0.845  0.322  1.0
  O  O8  1  0.118  0.066  0.345  1.0
  O  O9  1  0.538  0.145  0.660  1.0
  O  O10  1  0.371  0.138  0.998  1.0
  O  O11  1  0.955  0.258  0.946  1.0
  O  O12  1  0.836  0.293  0.499  1.0
  O  O13  1  0.343  0.434  0.268  1.0
  O  O14  1  0.733  0.508  0.149  1.0
  O  O15  1  0.267  0.492  0.851  1.0
  O  O16  1  0.657  0.566  0.732  1.0
  O  O17  1  0.164  0.707  0.501  1.0
  O  O18  1  0.045  0.742  0.054  1.0
  O  O19  1  0.629  0.862  0.002  1.0
  O  O20  1  0.462  0.855  0.340  1.0
  O  O21  1  0.882  0.934  0.655  1.0
[/CIF]
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The compound 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 6-coordinate geometry to one O(1), one O(4), one O(5), one O(7), and two equivalent O(3) atoms. In the second Li site, Li(2) is bonded to one O(1), one O(2), one O(5), one O(7), and two equivalent O(6) atoms to form distorted LiO6 pentagonal pyramids that share corners with three equivalent Cr(1)O4 tetrahedra, corners with three equivalent Cr(2)O4 tetrahedra, and  an edgeedge with one Li(2)O6 pentagonal pyramid. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form CrO4 tetrahedra that share corners with three equivalent Li(2)O6 pentagonal pyramids and  a cornercorner with one Cr(2)O4 tetrahedra. In the second Cr site, Cr(2) is bonded to one O(3), one O(4), one O(6), and one O(7) atom to form CrO4 tetrahedra that share corners with three equivalent Li(2)O6 pentagonal pyramids and  a cornercorner with one Cr(1)O4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Li(1), one Li(2), and one Cr(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Li(2) and one Cr(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Li(1) and one Cr(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Li(1), one Cr(1), and one Cr(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one Li(2), and one Cr(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to two equivalent 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(2) atom. is represented by the CIF card [CIF]
data_Li2Cr2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.469
_cell_length_b   6.735
_cell_length_c   6.763
_cell_angle_alpha   93.263
_cell_angle_beta   111.021
_cell_angle_gamma   93.369
_symmetry_Int_Tables_number   1
_cell_volume   273.616
_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  0.747  0.168  0.175  1.0
  Li  Li1  1  0.288  0.374  0.547  1.0
  Li  Li2  1  0.712  0.626  0.453  1.0
  Li  Li3  1  0.253  0.832  0.825  1.0
  Cr  Cr4  1  0.795  0.155  0.678  1.0
  Cr  Cr5  1  0.244  0.335  0.022  1.0
  Cr  Cr6  1  0.756  0.665  0.978  1.0
  Cr  Cr7  1  0.205  0.845  0.322  1.0
  O  O8  1  0.118  0.066  0.345  1.0
  O  O9  1  0.538  0.145  0.660  1.0
  O  O10  1  0.371  0.138  0.998  1.0
  O  O11  1  0.955  0.258  0.946  1.0
  O  O12  1  0.836  0.293  0.499  1.0
  O  O13  1  0.343  0.434  0.268  1.0
  O  O14  1  0.733  0.508  0.149  1.0
  O  O15  1  0.267  0.492  0.851  1.0
  O  O16  1  0.657  0.566  0.732  1.0
  O  O17  1  0.164  0.707  0.501  1.0
  O  O18  1  0.045  0.742  0.054  1.0
  O  O19  1  0.629  0.862  0.002  1.0
  O  O20  1  0.462  0.855  0.340  1.0
  O  O21  1  0.882  0.934  0.655  1.0
[/CIF]
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