The compound described by Li2CoP2O7 crystallizes in the monoclinic P2/m space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(3) and two equivalent O(5) atoms to form distorted LiO4 trigonal pyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and corners with two equivalent Li(4)O4 trigonal pyramids. In the second Li site, Li(2) is bonded to two equivalent O(4) and two equivalent O(6) atoms to form distorted LiO4 trigonal pyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and corners with two equivalent Li(3)O4 trigonal pyramids. In the third Li site, Li(3) is bonded to two equivalent O(4) and two equivalent O(7) atoms to form distorted LiO4 trigonal pyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and corners with two equivalent Li(2)O4 trigonal pyramids. In the fourth Li site, Li(4) is bonded to two equivalent O(3) and two equivalent O(8) atoms to form distorted LiO4 trigonal pyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and corners with two equivalent Li(1)O4 trigonal pyramids. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded in a square co-planar geometry to four equivalent O(6) atoms. In the second Co site, Co(2) is bonded in a square co-planar geometry to four equivalent O(7) atoms. In the third Co site, Co(3) is bonded in a square co-planar geometry to four equivalent O(5) atoms. In the fourth Co site, Co(4) is bonded in a square co-planar geometry to four equivalent O(8) atoms. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(3), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one Li(1)O4 trigonal pyramid,  a cornercorner with one Li(2)O4 trigonal pyramid,  a cornercorner with one Li(3)O4 trigonal pyramid, and  a cornercorner with one Li(4)O4 trigonal pyramid. In the second P site, P(2) is bonded to one O(2), one O(4), one O(5), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one Li(1)O4 trigonal pyramid,  a cornercorner with one Li(2)O4 trigonal pyramid,  a cornercorner with one Li(3)O4 trigonal pyramid, and  a cornercorner with one Li(4)O4 trigonal pyramid. There are eight inequivalent O sites. In the first O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one Co(3), and one P(2) atom. In the second O site, O(6) is bonded in a distorted trigonal planar geometry to one Li(2), one Co(1), and one P(1) atom. In the third O site, O(7) is bonded in a distorted trigonal planar geometry to one Li(3), one Co(2), and one P(1) atom. In the fourth O site, O(8) is bonded in a distorted trigonal planar geometry to one Li(4), one Co(4), and one P(2) atom. In the fifth O site, O(1) is bonded in a bent 120 degrees geometry to two equivalent P(1) atoms. In the sixth O site, O(2) is bonded in a bent 120 degrees geometry to two equivalent P(2) atoms. In the seventh O site, O(3) is bonded in a trigonal planar geometry to one Li(1), one Li(4), and one P(1) atom. In the eighth O site, O(4) is bonded in a trigonal planar geometry to one Li(2), one Li(3), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2CoP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.804
_cell_length_b   7.022
_cell_length_c   8.154
_cell_angle_alpha   115.407
_cell_angle_beta   114.573
_cell_angle_gamma   90.153
_symmetry_Int_Tables_number   1
_cell_volume   312.141
_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
  Co  Co0  1  0.000  0.000  0.000  1.0
  Co  Co1  1  0.000  0.500  0.000  1.0
  Li  Li2  1  0.769  0.769  0.538  1.0
  Li  Li3  1  0.231  0.731  0.462  1.0
  Li  Li4  1  0.769  0.269  0.538  1.0
  Li  Li5  1  0.231  0.231  0.462  1.0
  O  O6  1  0.426  0.250  1.000  1.0
  O  O7  1  0.574  0.750  0.000  1.0
  O  O8  1  0.663  0.443  0.385  1.0
  O  O9  1  0.722  0.942  0.385  1.0
  O  O10  1  0.278  0.058  0.615  1.0
  O  O11  1  0.337  0.557  0.615  1.0
  O  O12  1  0.703  0.820  0.775  1.0
  O  O13  1  0.073  0.955  0.775  1.0
  O  O14  1  0.929  0.683  0.225  1.0
  O  O15  1  0.296  0.542  0.224  1.0
  O  O16  1  0.704  0.458  0.776  1.0
  O  O17  1  0.071  0.317  0.775  1.0
  O  O18  1  0.297  0.180  0.225  1.0
  O  O19  1  0.927  0.045  0.225  1.0
  P  P20  1  0.795  0.861  0.220  1.0
  P  P21  1  0.425  0.359  0.220  1.0
  P  P22  1  0.575  0.641  0.780  1.0
  P  P23  1  0.205  0.139  0.780  1.0
[/CIF]
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The compound described by Li2CoP2O7 crystallizes in the monoclinic P2/m space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(3) and two equivalent O(5) atoms to form distorted LiO4 trigonal pyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and corners with two equivalent Li(4)O4 trigonal pyramids. In the second Li site, Li(2) is bonded to two equivalent O(4) and two equivalent O(6) atoms to form distorted LiO4 trigonal pyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and corners with two equivalent Li(3)O4 trigonal pyramids. In the third Li site, Li(3) is bonded to two equivalent O(4) and two equivalent O(7) atoms to form distorted LiO4 trigonal pyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and corners with two equivalent Li(2)O4 trigonal pyramids. In the fourth Li site, Li(4) is bonded to two equivalent O(3) and two equivalent O(8) atoms to form distorted LiO4 trigonal pyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and corners with two equivalent Li(1)O4 trigonal pyramids. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded in a square co-planar geometry to four equivalent O(6) atoms. In the second Co site, Co(2) is bonded in a square co-planar geometry to four equivalent O(7) atoms. In the third Co site, Co(3) is bonded in a square co-planar geometry to four equivalent O(5) atoms. In the fourth Co site, Co(4) is bonded in a square co-planar geometry to four equivalent O(8) atoms. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(3), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one Li(1)O4 trigonal pyramid,  a cornercorner with one Li(2)O4 trigonal pyramid,  a cornercorner with one Li(3)O4 trigonal pyramid, and  a cornercorner with one Li(4)O4 trigonal pyramid. In the second P site, P(2) is bonded to one O(2), one O(4), one O(5), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one Li(1)O4 trigonal pyramid,  a cornercorner with one Li(2)O4 trigonal pyramid,  a cornercorner with one Li(3)O4 trigonal pyramid, and  a cornercorner with one Li(4)O4 trigonal pyramid. There are eight inequivalent O sites. In the first O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one Co(3), and one P(2) atom. In the second O site, O(6) is bonded in a distorted trigonal planar geometry to one Li(2), one Co(1), and one P(1) atom. In the third O site, O(7) is bonded in a distorted trigonal planar geometry to one Li(3), one Co(2), and one P(1) atom. In the fourth O site, O(8) is bonded in a distorted trigonal planar geometry to one Li(4), one Co(4), and one P(2) atom. In the fifth O site, O(1) is bonded in a bent 120 degrees geometry to two equivalent P(1) atoms. In the sixth O site, O(2) is bonded in a bent 120 degrees geometry to two equivalent P(2) atoms. In the seventh O site, O(3) is bonded in a trigonal planar geometry to one Li(1), one Li(4), and one P(1) atom. In the eighth O site, O(4) is bonded in a trigonal planar geometry to one Li(2), one Li(3), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2CoP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.804
_cell_length_b   7.022
_cell_length_c   8.154
_cell_angle_alpha   115.407
_cell_angle_beta   114.573
_cell_angle_gamma   90.153
_symmetry_Int_Tables_number   1
_cell_volume   312.141
_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
  Co  Co0  1  0.000  0.000  0.000  1.0
  Co  Co1  1  0.000  0.500  0.000  1.0
  Li  Li2  1  0.769  0.769  0.538  1.0
  Li  Li3  1  0.231  0.731  0.462  1.0
  Li  Li4  1  0.769  0.269  0.538  1.0
  Li  Li5  1  0.231  0.231  0.462  1.0
  O  O6  1  0.426  0.250  1.000  1.0
  O  O7  1  0.574  0.750  0.000  1.0
  O  O8  1  0.663  0.443  0.385  1.0
  O  O9  1  0.722  0.942  0.385  1.0
  O  O10  1  0.278  0.058  0.615  1.0
  O  O11  1  0.337  0.557  0.615  1.0
  O  O12  1  0.703  0.820  0.775  1.0
  O  O13  1  0.073  0.955  0.775  1.0
  O  O14  1  0.929  0.683  0.225  1.0
  O  O15  1  0.296  0.542  0.224  1.0
  O  O16  1  0.704  0.458  0.776  1.0
  O  O17  1  0.071  0.317  0.775  1.0
  O  O18  1  0.297  0.180  0.225  1.0
  O  O19  1  0.927  0.045  0.225  1.0
  P  P20  1  0.795  0.861  0.220  1.0
  P  P21  1  0.425  0.359  0.220  1.0
  P  P22  1  0.575  0.641  0.780  1.0
  P  P23  1  0.205  0.139  0.780  1.0
[/CIF]
.