The material described by Li2Cr2O7 crystallizes in the triclinic P1 space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(3), one O(6), one O(8), and one O(9) atom to form LiO5 trigonal bipyramids that share  a cornercorner with one Cr(3)O4 tetrahedra, corners with two equivalent Cr(1)O4 tetrahedra, corners with two equivalent Cr(2)O4 tetrahedra, and  an edgeedge with one Li(2)O4 trigonal pyramid. In the second Li site, Li(2) is bonded to one O(1), one O(14), one O(8), and one O(9) atom to form distorted LiO4 trigonal pyramids that share  a cornercorner with one Cr(2)O4 tetrahedra,  a cornercorner with one Cr(3)O4 tetrahedra, corners with two equivalent Cr(1)O4 tetrahedra, and  an edgeedge with one Li(1)O5 trigonal bipyramid. In the third Li site, Li(3) is bonded in a 4-coordinate geometry to one O(10), one O(12), one O(14), and one O(3) atom. In the fourth Li site, Li(4) is bonded in a see-saw-like geometry to one O(11), one O(13), one O(4), and one O(6) atom. There are four inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(11), one O(2), and one O(8) atom to form CrO4 tetrahedra that share  a cornercorner with one Cr(4)O4 tetrahedra, corners with two equivalent Li(1)O5 trigonal bipyramids, and corners with two equivalent Li(2)O4 trigonal pyramids. In the second Cr site, Cr(2) is bonded to one O(3), one O(4), one O(7), and one O(9) atom to form CrO4 tetrahedra that share  a cornercorner with one Cr(4)O4 tetrahedra, corners with two equivalent Li(1)O5 trigonal bipyramids, and  a cornercorner with one Li(2)O4 trigonal pyramid. In the third Cr site, Cr(3) is bonded to one O(12), one O(14), one O(5), and one O(6) atom to form CrO4 tetrahedra that share  a cornercorner with one Li(1)O5 trigonal bipyramid and  a cornercorner with one Li(2)O4 trigonal pyramid. In the fourth Cr site, Cr(4) is bonded to one O(10), one O(11), one O(13), and one O(7) atom to form corner-sharing CrO4 tetrahedra. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to one Li(2) and one Cr(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Li(1) and one Cr(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Li(1), one Li(3), and one Cr(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Li(4) and one Cr(2) atom. In the fifth O site, O(5) is bonded in a single-bond geometry to one Cr(3) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Li(1), one Li(4), and one Cr(3) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Cr(2) and one Cr(4) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Li(1), one Li(2), and one Cr(1) atom. In the ninth O site, O(9) is bonded in a distorted trigonal non-coplanar geometry to one Li(1), one Li(2), and one Cr(2) atom. In the tenth O site, O(10) is bonded in a distorted bent 120 degrees geometry to one Li(3) and one Cr(4) atom. In the eleventh O site, O(11) is bonded in a trigonal planar geometry to one Li(4), one Cr(1), and one Cr(4) atom. In the twelfth O site, O(12) is bonded in a bent 150 degrees geometry to one Li(3) and one Cr(3) atom. In the thirteenth O site, O(13) is bonded in a distorted bent 150 degrees geometry to one Li(4) and one Cr(4) atom. In the fourteenth O site, O(14) is bonded in a 3-coordinate geometry to one Li(2), one Li(3), and one Cr(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2Cr2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.509
_cell_length_b   6.688
_cell_length_c   7.191
_cell_angle_alpha   83.522
_cell_angle_beta   67.036
_cell_angle_gamma   83.827
_symmetry_Int_Tables_number   1
_cell_volume   285.708
_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  0.091  0.543  0.369  1.0
  Li  Li1  1  0.732  0.830  0.222  1.0
  Li  Li2  1  0.598  0.630  0.880  1.0
  Li  Li3  1  0.970  0.216  0.809  1.0
  Cr  Cr4  1  0.197  0.042  0.199  1.0
  Cr  Cr5  1  0.638  0.386  0.288  1.0
  Cr  Cr6  1  0.108  0.684  0.780  1.0
  Cr  Cr7  1  0.505  0.122  0.732  1.0
  O  O8  1  0.443  0.960  0.189  1.0
  O  O9  1  0.106  0.233  0.339  1.0
  O  O10  1  0.476  0.514  0.187  1.0
  O  O11  1  0.811  0.232  0.128  1.0
  O  O12  1  0.237  0.845  0.593  1.0
  O  O13  1  0.025  0.496  0.689  1.0
  O  O14  1  0.475  0.243  0.516  1.0
  O  O15  1  0.024  0.861  0.285  1.0
  O  O16  1  0.777  0.544  0.344  1.0
  O  O17  1  0.619  0.898  0.690  1.0
  O  O18  1  0.242  0.116  0.929  1.0
  O  O19  1  0.279  0.598  0.896  1.0
  O  O20  1  0.666  0.248  0.791  1.0
  O  O21  1  0.874  0.802  0.939  1.0
[/CIF]
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The material described by Li2Cr2O7 crystallizes in the triclinic P1 space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(3), one O(6), one O(8), and one O(9) atom to form LiO5 trigonal bipyramids that share  a cornercorner with one Cr(3)O4 tetrahedra, corners with two equivalent Cr(1)O4 tetrahedra, corners with two equivalent Cr(2)O4 tetrahedra, and  an edgeedge with one Li(2)O4 trigonal pyramid. In the second Li site, Li(2) is bonded to one O(1), one O(14), one O(8), and one O(9) atom to form distorted LiO4 trigonal pyramids that share  a cornercorner with one Cr(2)O4 tetrahedra,  a cornercorner with one Cr(3)O4 tetrahedra, corners with two equivalent Cr(1)O4 tetrahedra, and  an edgeedge with one Li(1)O5 trigonal bipyramid. In the third Li site, Li(3) is bonded in a 4-coordinate geometry to one O(10), one O(12), one O(14), and one O(3) atom. In the fourth Li site, Li(4) is bonded in a see-saw-like geometry to one O(11), one O(13), one O(4), and one O(6) atom. There are four inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(11), one O(2), and one O(8) atom to form CrO4 tetrahedra that share  a cornercorner with one Cr(4)O4 tetrahedra, corners with two equivalent Li(1)O5 trigonal bipyramids, and corners with two equivalent Li(2)O4 trigonal pyramids. In the second Cr site, Cr(2) is bonded to one O(3), one O(4), one O(7), and one O(9) atom to form CrO4 tetrahedra that share  a cornercorner with one Cr(4)O4 tetrahedra, corners with two equivalent Li(1)O5 trigonal bipyramids, and  a cornercorner with one Li(2)O4 trigonal pyramid. In the third Cr site, Cr(3) is bonded to one O(12), one O(14), one O(5), and one O(6) atom to form CrO4 tetrahedra that share  a cornercorner with one Li(1)O5 trigonal bipyramid and  a cornercorner with one Li(2)O4 trigonal pyramid. In the fourth Cr site, Cr(4) is bonded to one O(10), one O(11), one O(13), and one O(7) atom to form corner-sharing CrO4 tetrahedra. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to one Li(2) and one Cr(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Li(1) and one Cr(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Li(1), one Li(3), and one Cr(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Li(4) and one Cr(2) atom. In the fifth O site, O(5) is bonded in a single-bond geometry to one Cr(3) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Li(1), one Li(4), and one Cr(3) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Cr(2) and one Cr(4) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Li(1), one Li(2), and one Cr(1) atom. In the ninth O site, O(9) is bonded in a distorted trigonal non-coplanar geometry to one Li(1), one Li(2), and one Cr(2) atom. In the tenth O site, O(10) is bonded in a distorted bent 120 degrees geometry to one Li(3) and one Cr(4) atom. In the eleventh O site, O(11) is bonded in a trigonal planar geometry to one Li(4), one Cr(1), and one Cr(4) atom. In the twelfth O site, O(12) is bonded in a bent 150 degrees geometry to one Li(3) and one Cr(3) atom. In the thirteenth O site, O(13) is bonded in a distorted bent 150 degrees geometry to one Li(4) and one Cr(4) atom. In the fourteenth O site, O(14) is bonded in a 3-coordinate geometry to one Li(2), one Li(3), and one Cr(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2Cr2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.509
_cell_length_b   6.688
_cell_length_c   7.191
_cell_angle_alpha   83.522
_cell_angle_beta   67.036
_cell_angle_gamma   83.827
_symmetry_Int_Tables_number   1
_cell_volume   285.708
_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  0.091  0.543  0.369  1.0
  Li  Li1  1  0.732  0.830  0.222  1.0
  Li  Li2  1  0.598  0.630  0.880  1.0
  Li  Li3  1  0.970  0.216  0.809  1.0
  Cr  Cr4  1  0.197  0.042  0.199  1.0
  Cr  Cr5  1  0.638  0.386  0.288  1.0
  Cr  Cr6  1  0.108  0.684  0.780  1.0
  Cr  Cr7  1  0.505  0.122  0.732  1.0
  O  O8  1  0.443  0.960  0.189  1.0
  O  O9  1  0.106  0.233  0.339  1.0
  O  O10  1  0.476  0.514  0.187  1.0
  O  O11  1  0.811  0.232  0.128  1.0
  O  O12  1  0.237  0.845  0.593  1.0
  O  O13  1  0.025  0.496  0.689  1.0
  O  O14  1  0.475  0.243  0.516  1.0
  O  O15  1  0.024  0.861  0.285  1.0
  O  O16  1  0.777  0.544  0.344  1.0
  O  O17  1  0.619  0.898  0.690  1.0
  O  O18  1  0.242  0.116  0.929  1.0
  O  O19  1  0.279  0.598  0.896  1.0
  O  O20  1  0.666  0.248  0.791  1.0
  O  O21  1  0.874  0.802  0.939  1.0
[/CIF]
.