The crystal structure described by Na2CuP2O7 crystallizes in the monoclinic C2/c space group. Na(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form distorted NaO4 tetrahedra that share corners with four equivalent P(1)O4 tetrahedra and  an edgeedge with one Na(1)O4 tetrahedra. Cu(1) is bonded in a square co-planar geometry to two equivalent O(2) and two equivalent O(3) atoms. P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra and corners with four equivalent Na(1)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Na(1) and one P(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Na(1), one Cu(1), and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Na(1), one Cu(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to two equivalent P(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2CuP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.833
_cell_length_b   8.833
_cell_length_c   9.007
_cell_angle_alpha   66.226
_cell_angle_beta   66.226
_cell_angle_gamma   33.968
_symmetry_Int_Tables_number   1
_cell_volume   356.036
_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
  Na  Na0  1  0.831  0.555  0.432  1.0
  Na  Na1  1  0.555  0.831  0.932  1.0
  Na  Na2  1  0.445  0.169  0.068  1.0
  Na  Na3  1  0.169  0.445  0.568  1.0
  Cu  Cu4  1  0.500  0.500  0.500  1.0
  Cu  Cu5  1  0.500  0.500  0.000  1.0
  P  P6  1  0.947  0.237  0.188  1.0
  P  P7  1  0.237  0.947  0.688  1.0
  P  P8  1  0.763  0.053  0.312  1.0
  P  P9  1  0.053  0.763  0.812  1.0
  O  O10  1  0.214  0.119  0.122  1.0
  O  O11  1  0.119  0.214  0.622  1.0
  O  O12  1  0.754  0.428  0.057  1.0
  O  O13  1  0.804  0.379  0.340  1.0
  O  O14  1  0.428  0.754  0.557  1.0
  O  O15  1  0.379  0.804  0.840  1.0
  O  O16  1  0.015  0.985  0.250  1.0
  O  O17  1  0.985  0.015  0.750  1.0
  O  O18  1  0.621  0.196  0.160  1.0
  O  O19  1  0.572  0.246  0.443  1.0
  O  O20  1  0.196  0.621  0.660  1.0
  O  O21  1  0.246  0.572  0.943  1.0
  O  O22  1  0.881  0.786  0.378  1.0
  O  O23  1  0.786  0.881  0.878  1.0
[/CIF]
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The crystal structure described by Na2CuP2O7 crystallizes in the monoclinic C2/c space group. Na(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form distorted NaO4 tetrahedra that share corners with four equivalent P(1)O4 tetrahedra and  an edgeedge with one Na(1)O4 tetrahedra. Cu(1) is bonded in a square co-planar geometry to two equivalent O(2) and two equivalent O(3) atoms. P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra and corners with four equivalent Na(1)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Na(1) and one P(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Na(1), one Cu(1), and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Na(1), one Cu(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to two equivalent P(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2CuP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.833
_cell_length_b   8.833
_cell_length_c   9.007
_cell_angle_alpha   66.226
_cell_angle_beta   66.226
_cell_angle_gamma   33.968
_symmetry_Int_Tables_number   1
_cell_volume   356.036
_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
  Na  Na0  1  0.831  0.555  0.432  1.0
  Na  Na1  1  0.555  0.831  0.932  1.0
  Na  Na2  1  0.445  0.169  0.068  1.0
  Na  Na3  1  0.169  0.445  0.568  1.0
  Cu  Cu4  1  0.500  0.500  0.500  1.0
  Cu  Cu5  1  0.500  0.500  0.000  1.0
  P  P6  1  0.947  0.237  0.188  1.0
  P  P7  1  0.237  0.947  0.688  1.0
  P  P8  1  0.763  0.053  0.312  1.0
  P  P9  1  0.053  0.763  0.812  1.0
  O  O10  1  0.214  0.119  0.122  1.0
  O  O11  1  0.119  0.214  0.622  1.0
  O  O12  1  0.754  0.428  0.057  1.0
  O  O13  1  0.804  0.379  0.340  1.0
  O  O14  1  0.428  0.754  0.557  1.0
  O  O15  1  0.379  0.804  0.840  1.0
  O  O16  1  0.015  0.985  0.250  1.0
  O  O17  1  0.985  0.015  0.750  1.0
  O  O18  1  0.621  0.196  0.160  1.0
  O  O19  1  0.572  0.246  0.443  1.0
  O  O20  1  0.196  0.621  0.660  1.0
  O  O21  1  0.246  0.572  0.943  1.0
  O  O22  1  0.881  0.786  0.378  1.0
  O  O23  1  0.786  0.881  0.878  1.0
[/CIF]
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