The compound described by Li3CrP2O9 crystallizes in the triclinic P1 space group. There are six inequivalent Li sites. In the first Li site, Li(1) is bonded in a 5-coordinate geometry to one O(1), one O(13), one O(15), one O(5), and one O(7) atom. In the second Li site, Li(2) is bonded to one O(1), one O(10), one O(11), one O(14), one O(16), and one O(8) atom to form distorted LiO6 octahedra that share corners with two equivalent Cr(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  an edgeedge with one P(1)O4 tetrahedra, and  an edgeedge with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 60-61°. In the third Li site, Li(3) is bonded in a 5-coordinate geometry to one O(10), one O(4), one O(6), one O(8), and one O(9) atom. In the fourth Li site, Li(4) is bonded in a 5-coordinate geometry to one O(11), one O(16), one O(17), one O(2), and one O(5) atom. In the fifth Li site, Li(5) is bonded to one O(15), one O(17), one O(18), one O(3), one O(7), and one O(9) atom to form distorted LiO6 octahedra that share  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra,  an edgeedge with one P(2)O4 tetrahedra, and  an edgeedge with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 57-58°. In the sixth Li site, Li(6) is bonded in a 5-coordinate geometry to one O(12), one O(14), one O(18), one O(3), and one O(4) atom. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(10), one O(11), one O(13), one O(3), one O(4), and one O(5) atom to form CrO6 octahedra that share  a cornercorner with one Li(5)O6 octahedra, corners with two equivalent Li(2)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, and  a cornercorner with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 40-61°. In the second Cr site, Cr(2) is bonded to one O(12), one O(2), one O(4), one O(5), one O(6), and one O(7) atom to form CrO6 octahedra that share  a cornercorner with one Li(5)O6 octahedra, corners with two equivalent Cr(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, and  a cornercorner with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 40-58°. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(10), one O(18), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Li(5)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  an edgeedge with one Li(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-57°. In the second P site, P(2) is bonded to one O(13), one O(17), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Li(2)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  an edgeedge with one Li(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-59°. In the third P site, P(3) is bonded to one O(12), one O(16), one O(3), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Li(2)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  an edgeedge with one Li(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-58°. In the fourth P site, P(4) is bonded to one O(11), one O(14), one O(15), and one O(2) atom to form PO4 tetrahedra that share  a cornercorner with one Li(5)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  an edgeedge with one Li(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-58°. There are eighteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Li(1), one Li(2), and one P(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Li(4), one Cr(2), and one P(4) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Li(5), one Li(6), one Cr(1), and one P(3) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Li(3), one Li(6), one Cr(1), and one Cr(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Li(1), one Li(4), one Cr(1), and one Cr(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Li(3), one Cr(2), and one P(1) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Li(1), one Li(5), one Cr(2), and one P(2) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Li(2), one Li(3), and one P(2) atom. In the ninth O site, O(9) is bonded in a distorted T-shaped geometry to one Li(3), one Li(5), and one P(3) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Li(2), one Li(3), one Cr(1), and one P(1) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Li(2), one Li(4), one Cr(1), and one P(4) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Li(6), one Cr(2), and one P(3) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal planar geometry to one Li(1), one Cr(1), and one P(2) atom. In the fourteenth O site, O(14) is bonded in a 3-coordinate geometry to one Li(2), one Li(6), and one P(4) atom. In the fifteenth O site, O(15) is bonded in a distorted trigonal planar geometry to one Li(1), one Li(5), and one P(4) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal planar geometry to one Li(2), one Li(4), and one P(3) atom. In the seventeenth O site, O(17) is bonded in a distorted T-shaped geometry to one Li(4), one Li(5), and one P(2) atom. In the eighteenth O site, O(18) is bonded in a distorted T-shaped geometry to one Li(5), one Li(6), and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li3CrP2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.841
_cell_length_b   7.134
_cell_length_c   8.006
_cell_angle_alpha   88.997
_cell_angle_beta   115.228
_cell_angle_gamma   92.761
_symmetry_Int_Tables_number   1
_cell_volume   353.023
_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  0.918  0.758  0.806  1.0
  Li  Li1  1  1.000  0.500  0.502  1.0
  Li  Li2  1  0.380  0.307  0.749  1.0
  Li  Li3  1  0.604  0.692  0.250  1.0
  Li  Li4  1  0.756  0.997  0.003  1.0
  Li  Li5  1  0.121  0.244  0.196  1.0
  Cr  Cr6  1  0.004  0.995  0.506  1.0
  Cr  Cr7  1  0.498  0.003  0.497  1.0
  P  P8  1  0.876  0.293  0.749  1.0
  P  P9  1  0.392  0.757  0.795  1.0
  P  P10  1  0.616  0.241  0.204  1.0
  P  P11  1  0.113  0.707  0.251  1.0
  O  O12  1  0.888  0.505  0.741  1.0
  O  O13  1  0.358  0.784  0.345  1.0
  O  O14  1  0.820  0.116  0.263  1.0
  O  O15  1  0.225  0.090  0.475  1.0
  O  O16  1  0.768  0.914  0.523  1.0
  O  O17  1  0.630  0.222  0.641  1.0
  O  O18  1  0.550  0.869  0.725  1.0
  O  O19  1  0.328  0.564  0.704  1.0
  O  O20  1  0.511  0.238  0.996  1.0
  O  O21  1  0.010  0.230  0.640  1.0
  O  O22  1  0.993  0.763  0.373  1.0
  O  O23  1  0.451  0.145  0.275  1.0
  O  O24  1  0.179  0.872  0.735  1.0
  O  O25  1  0.114  0.495  0.258  1.0
  O  O26  1  0.005  0.799  0.063  1.0
  O  O27  1  0.681  0.434  0.296  1.0
  O  O28  1  0.515  0.764  0.003  1.0
  O  O29  1  0.949  0.201  0.937  1.0
[/CIF]
.
The compound described by Li3CrP2O9 crystallizes in the triclinic P1 space group. There are six inequivalent Li sites. In the first Li site, Li(1) is bonded in a 5-coordinate geometry to one O(1), one O(13), one O(15), one O(5), and one O(7) atom. In the second Li site, Li(2) is bonded to one O(1), one O(10), one O(11), one O(14), one O(16), and one O(8) atom to form distorted LiO6 octahedra that share corners with two equivalent Cr(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  an edgeedge with one P(1)O4 tetrahedra, and  an edgeedge with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 60-61°. In the third Li site, Li(3) is bonded in a 5-coordinate geometry to one O(10), one O(4), one O(6), one O(8), and one O(9) atom. In the fourth Li site, Li(4) is bonded in a 5-coordinate geometry to one O(11), one O(16), one O(17), one O(2), and one O(5) atom. In the fifth Li site, Li(5) is bonded to one O(15), one O(17), one O(18), one O(3), one O(7), and one O(9) atom to form distorted LiO6 octahedra that share  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra,  an edgeedge with one P(2)O4 tetrahedra, and  an edgeedge with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 57-58°. In the sixth Li site, Li(6) is bonded in a 5-coordinate geometry to one O(12), one O(14), one O(18), one O(3), and one O(4) atom. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(10), one O(11), one O(13), one O(3), one O(4), and one O(5) atom to form CrO6 octahedra that share  a cornercorner with one Li(5)O6 octahedra, corners with two equivalent Li(2)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, and  a cornercorner with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 40-61°. In the second Cr site, Cr(2) is bonded to one O(12), one O(2), one O(4), one O(5), one O(6), and one O(7) atom to form CrO6 octahedra that share  a cornercorner with one Li(5)O6 octahedra, corners with two equivalent Cr(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, and  a cornercorner with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 40-58°. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(10), one O(18), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Li(5)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  an edgeedge with one Li(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-57°. In the second P site, P(2) is bonded to one O(13), one O(17), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Li(2)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  an edgeedge with one Li(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-59°. In the third P site, P(3) is bonded to one O(12), one O(16), one O(3), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Li(2)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  an edgeedge with one Li(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-58°. In the fourth P site, P(4) is bonded to one O(11), one O(14), one O(15), and one O(2) atom to form PO4 tetrahedra that share  a cornercorner with one Li(5)O6 octahedra,  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra, and  an edgeedge with one Li(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-58°. There are eighteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Li(1), one Li(2), and one P(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Li(4), one Cr(2), and one P(4) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Li(5), one Li(6), one Cr(1), and one P(3) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Li(3), one Li(6), one Cr(1), and one Cr(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Li(1), one Li(4), one Cr(1), and one Cr(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Li(3), one Cr(2), and one P(1) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Li(1), one Li(5), one Cr(2), and one P(2) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Li(2), one Li(3), and one P(2) atom. In the ninth O site, O(9) is bonded in a distorted T-shaped geometry to one Li(3), one Li(5), and one P(3) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Li(2), one Li(3), one Cr(1), and one P(1) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Li(2), one Li(4), one Cr(1), and one P(4) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Li(6), one Cr(2), and one P(3) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal planar geometry to one Li(1), one Cr(1), and one P(2) atom. In the fourteenth O site, O(14) is bonded in a 3-coordinate geometry to one Li(2), one Li(6), and one P(4) atom. In the fifteenth O site, O(15) is bonded in a distorted trigonal planar geometry to one Li(1), one Li(5), and one P(4) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal planar geometry to one Li(2), one Li(4), and one P(3) atom. In the seventeenth O site, O(17) is bonded in a distorted T-shaped geometry to one Li(4), one Li(5), and one P(2) atom. In the eighteenth O site, O(18) is bonded in a distorted T-shaped geometry to one Li(5), one Li(6), and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li3CrP2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.841
_cell_length_b   7.134
_cell_length_c   8.006
_cell_angle_alpha   88.997
_cell_angle_beta   115.228
_cell_angle_gamma   92.761
_symmetry_Int_Tables_number   1
_cell_volume   353.023
_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  0.918  0.758  0.806  1.0
  Li  Li1  1  1.000  0.500  0.502  1.0
  Li  Li2  1  0.380  0.307  0.749  1.0
  Li  Li3  1  0.604  0.692  0.250  1.0
  Li  Li4  1  0.756  0.997  0.003  1.0
  Li  Li5  1  0.121  0.244  0.196  1.0
  Cr  Cr6  1  0.004  0.995  0.506  1.0
  Cr  Cr7  1  0.498  0.003  0.497  1.0
  P  P8  1  0.876  0.293  0.749  1.0
  P  P9  1  0.392  0.757  0.795  1.0
  P  P10  1  0.616  0.241  0.204  1.0
  P  P11  1  0.113  0.707  0.251  1.0
  O  O12  1  0.888  0.505  0.741  1.0
  O  O13  1  0.358  0.784  0.345  1.0
  O  O14  1  0.820  0.116  0.263  1.0
  O  O15  1  0.225  0.090  0.475  1.0
  O  O16  1  0.768  0.914  0.523  1.0
  O  O17  1  0.630  0.222  0.641  1.0
  O  O18  1  0.550  0.869  0.725  1.0
  O  O19  1  0.328  0.564  0.704  1.0
  O  O20  1  0.511  0.238  0.996  1.0
  O  O21  1  0.010  0.230  0.640  1.0
  O  O22  1  0.993  0.763  0.373  1.0
  O  O23  1  0.451  0.145  0.275  1.0
  O  O24  1  0.179  0.872  0.735  1.0
  O  O25  1  0.114  0.495  0.258  1.0
  O  O26  1  0.005  0.799  0.063  1.0
  O  O27  1  0.681  0.434  0.296  1.0
  O  O28  1  0.515  0.764  0.003  1.0
  O  O29  1  0.949  0.201  0.937  1.0
[/CIF]
.