The material described by Na2CoP2O7 crystallizes in the triclinic P-1 space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a rectangular see-saw-like geometry to one O(10), one O(3), one O(6), and one O(7) atom. In the second Na site, Na(2) is bonded in a rectangular see-saw-like geometry to one O(4), one O(5), one O(8), and one O(9) atom. In the third Na site, Na(3) is bonded in a rectangular see-saw-like geometry to one O(12), one O(13), one O(3), and one O(5) atom. In the fourth Na site, Na(4) is bonded in a rectangular see-saw-like geometry to one O(11), one O(14), one O(4), and one O(6) atom. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded in a square co-planar geometry to one O(10), one O(7), one O(8), and one O(9) atom. In the second Co site, Co(2) is bonded in a square co-planar geometry to two equivalent O(11) and two equivalent O(14) atoms. In the third Co site, Co(3) is bonded in a square co-planar geometry to two equivalent O(12) and two equivalent O(13) atoms. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(13), one O(4), and one O(7) atom to form corner-sharing PO4 tetrahedra. In the second P site, P(2) is bonded to one O(14), one O(2), one O(3), and one O(8) atom to form corner-sharing PO4 tetrahedra. In the third P site, P(3) is bonded to one O(1), one O(12), one O(6), and one O(9) atom to form corner-sharing PO4 tetrahedra. In the fourth P site, P(4) is bonded to one O(10), one O(11), one O(2), and one O(5) atom to form corner-sharing PO4 tetrahedra. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one P(1) and one P(3) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one P(2) and one P(4) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one Na(3), and one P(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal non-coplanar geometry to one Na(2), one Na(4), and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Na(2), one Na(3), and one P(4) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one Na(4), and one P(3) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Na(1), one Co(1), and one P(1) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Na(2), one Co(1), and one P(2) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Na(2), one Co(1), and one P(3) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Na(1), one Co(1), and one P(4) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal planar geometry to one Na(4), one Co(2), and one P(4) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Na(3), one Co(3), and one P(3) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal planar geometry to one Na(3), one Co(3), and one P(1) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal planar geometry to one Na(4), one Co(2), and one P(2) atom. is represented by the CIF card [CIF]
data_Na2CoP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.526
_cell_length_b   8.155
_cell_length_c   8.683
_cell_angle_alpha   62.028
_cell_angle_beta   67.933
_cell_angle_gamma   89.946
_symmetry_Int_Tables_number   1
_cell_volume   369.483
_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  0.500  1.000  1.0
  Co  Co1  1  0.000  0.000  0.000  1.0
  Na  Na2  1  0.758  0.258  0.484  1.0
  Na  Na3  1  0.757  0.757  0.485  1.0
  Na  Na4  1  0.242  0.742  0.516  1.0
  Na  Na5  1  0.243  0.243  0.515  1.0
  O  O6  1  0.570  0.750  1.000  1.0
  O  O7  1  0.430  0.250  0.000  1.0
  O  O8  1  0.654  0.430  0.639  1.0
  O  O9  1  0.707  0.931  0.639  1.0
  O  O10  1  0.346  0.570  0.361  1.0
  O  O11  1  0.293  0.069  0.361  1.0
  O  O12  1  0.718  0.487  0.210  1.0
  O  O13  1  0.073  0.303  0.210  1.0
  O  O14  1  0.069  0.990  0.210  1.0
  O  O15  1  0.721  0.800  0.210  1.0
  O  O16  1  0.282  0.513  0.790  1.0
  O  O17  1  0.927  0.697  0.790  1.0
  O  O18  1  0.931  0.010  0.790  1.0
  O  O19  1  0.279  0.200  0.790  1.0
  P  P20  1  0.586  0.646  0.206  1.0
  P  P21  1  0.208  0.147  0.206  1.0
  P  P22  1  0.414  0.354  0.794  1.0
  P  P23  1  0.792  0.853  0.794  1.0
[/CIF]
.
The material described by Na2CoP2O7 crystallizes in the triclinic P-1 space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a rectangular see-saw-like geometry to one O(10), one O(3), one O(6), and one O(7) atom. In the second Na site, Na(2) is bonded in a rectangular see-saw-like geometry to one O(4), one O(5), one O(8), and one O(9) atom. In the third Na site, Na(3) is bonded in a rectangular see-saw-like geometry to one O(12), one O(13), one O(3), and one O(5) atom. In the fourth Na site, Na(4) is bonded in a rectangular see-saw-like geometry to one O(11), one O(14), one O(4), and one O(6) atom. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded in a square co-planar geometry to one O(10), one O(7), one O(8), and one O(9) atom. In the second Co site, Co(2) is bonded in a square co-planar geometry to two equivalent O(11) and two equivalent O(14) atoms. In the third Co site, Co(3) is bonded in a square co-planar geometry to two equivalent O(12) and two equivalent O(13) atoms. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(13), one O(4), and one O(7) atom to form corner-sharing PO4 tetrahedra. In the second P site, P(2) is bonded to one O(14), one O(2), one O(3), and one O(8) atom to form corner-sharing PO4 tetrahedra. In the third P site, P(3) is bonded to one O(1), one O(12), one O(6), and one O(9) atom to form corner-sharing PO4 tetrahedra. In the fourth P site, P(4) is bonded to one O(10), one O(11), one O(2), and one O(5) atom to form corner-sharing PO4 tetrahedra. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one P(1) and one P(3) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one P(2) and one P(4) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one Na(3), and one P(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal non-coplanar geometry to one Na(2), one Na(4), and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Na(2), one Na(3), and one P(4) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one Na(4), and one P(3) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Na(1), one Co(1), and one P(1) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Na(2), one Co(1), and one P(2) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Na(2), one Co(1), and one P(3) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Na(1), one Co(1), and one P(4) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal planar geometry to one Na(4), one Co(2), and one P(4) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Na(3), one Co(3), and one P(3) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal planar geometry to one Na(3), one Co(3), and one P(1) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal planar geometry to one Na(4), one Co(2), and one P(2) atom. is represented by the CIF card [CIF]
data_Na2CoP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.526
_cell_length_b   8.155
_cell_length_c   8.683
_cell_angle_alpha   62.028
_cell_angle_beta   67.933
_cell_angle_gamma   89.946
_symmetry_Int_Tables_number   1
_cell_volume   369.483
_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  0.500  1.000  1.0
  Co  Co1  1  0.000  0.000  0.000  1.0
  Na  Na2  1  0.758  0.258  0.484  1.0
  Na  Na3  1  0.757  0.757  0.485  1.0
  Na  Na4  1  0.242  0.742  0.516  1.0
  Na  Na5  1  0.243  0.243  0.515  1.0
  O  O6  1  0.570  0.750  1.000  1.0
  O  O7  1  0.430  0.250  0.000  1.0
  O  O8  1  0.654  0.430  0.639  1.0
  O  O9  1  0.707  0.931  0.639  1.0
  O  O10  1  0.346  0.570  0.361  1.0
  O  O11  1  0.293  0.069  0.361  1.0
  O  O12  1  0.718  0.487  0.210  1.0
  O  O13  1  0.073  0.303  0.210  1.0
  O  O14  1  0.069  0.990  0.210  1.0
  O  O15  1  0.721  0.800  0.210  1.0
  O  O16  1  0.282  0.513  0.790  1.0
  O  O17  1  0.927  0.697  0.790  1.0
  O  O18  1  0.931  0.010  0.790  1.0
  O  O19  1  0.279  0.200  0.790  1.0
  P  P20  1  0.586  0.646  0.206  1.0
  P  P21  1  0.208  0.147  0.206  1.0
  P  P22  1  0.414  0.354  0.794  1.0
  P  P23  1  0.792  0.853  0.794  1.0
[/CIF]
.