The crystal structure described by LiNa3P2O7 crystallizes in the orthorhombic C222_1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Li(1) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form LiO4 tetrahedra that share corners with four equivalent P(1)O4 tetrahedra. 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 two equivalent Li(1)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(3) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), one Li(1), and one P(1) atom. In the second O site, O(4) is bonded in a bent 120 degrees geometry to two equivalent P(1) atoms. In the third O site, O(1) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), one Li(1), and one P(1) atom. In the fourth O site, O(2) is bonded to one Na(1), two equivalent Na(2), and one P(1) atom to form distorted corner-sharing ONa3P trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na3LiP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.393
_cell_length_b   5.393
_cell_length_c   12.421
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   117.937
_symmetry_Int_Tables_number   1
_cell_volume   319.182
_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  0.350  0.350  0.500  1.0
  Na  Na1  1  0.650  0.650  0.000  1.0
  Na  Na2  1  0.047  0.702  0.619  1.0
  Na  Na3  1  0.702  0.047  0.381  1.0
  Na  Na4  1  0.953  0.298  0.119  1.0
  Na  Na5  1  0.298  0.953  0.881  1.0
  Li  Li6  1  0.537  0.463  0.750  1.0
  Li  Li7  1  0.463  0.537  0.250  1.0
  P  P8  1  0.690  0.028  0.649  1.0
  P  P9  1  0.028  0.690  0.351  1.0
  P  P10  1  0.310  0.972  0.149  1.0
  P  P11  1  0.972  0.310  0.851  1.0
  O  O12  1  0.585  0.714  0.628  1.0
  O  O13  1  0.714  0.585  0.372  1.0
  O  O14  1  0.415  0.286  0.128  1.0
  O  O15  1  0.286  0.415  0.872  1.0
  O  O16  1  0.869  0.218  0.557  1.0
  O  O17  1  0.218  0.869  0.443  1.0
  O  O18  1  0.131  0.782  0.057  1.0
  O  O19  1  0.782  0.131  0.943  1.0
  O  O20  1  0.456  0.094  0.686  1.0
  O  O21  1  0.094  0.456  0.314  1.0
  O  O22  1  0.544  0.906  0.186  1.0
  O  O23  1  0.906  0.544  0.814  1.0
  O  O24  1  0.907  0.093  0.750  1.0
  O  O25  1  0.093  0.907  0.250  1.0
[/CIF]
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The crystal structure described by LiNa3P2O7 crystallizes in the orthorhombic C222_1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Li(1) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form LiO4 tetrahedra that share corners with four equivalent P(1)O4 tetrahedra. 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 two equivalent Li(1)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(3) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), one Li(1), and one P(1) atom. In the second O site, O(4) is bonded in a bent 120 degrees geometry to two equivalent P(1) atoms. In the third O site, O(1) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), one Li(1), and one P(1) atom. In the fourth O site, O(2) is bonded to one Na(1), two equivalent Na(2), and one P(1) atom to form distorted corner-sharing ONa3P trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na3LiP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.393
_cell_length_b   5.393
_cell_length_c   12.421
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   117.937
_symmetry_Int_Tables_number   1
_cell_volume   319.182
_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  0.350  0.350  0.500  1.0
  Na  Na1  1  0.650  0.650  0.000  1.0
  Na  Na2  1  0.047  0.702  0.619  1.0
  Na  Na3  1  0.702  0.047  0.381  1.0
  Na  Na4  1  0.953  0.298  0.119  1.0
  Na  Na5  1  0.298  0.953  0.881  1.0
  Li  Li6  1  0.537  0.463  0.750  1.0
  Li  Li7  1  0.463  0.537  0.250  1.0
  P  P8  1  0.690  0.028  0.649  1.0
  P  P9  1  0.028  0.690  0.351  1.0
  P  P10  1  0.310  0.972  0.149  1.0
  P  P11  1  0.972  0.310  0.851  1.0
  O  O12  1  0.585  0.714  0.628  1.0
  O  O13  1  0.714  0.585  0.372  1.0
  O  O14  1  0.415  0.286  0.128  1.0
  O  O15  1  0.286  0.415  0.872  1.0
  O  O16  1  0.869  0.218  0.557  1.0
  O  O17  1  0.218  0.869  0.443  1.0
  O  O18  1  0.131  0.782  0.057  1.0
  O  O19  1  0.782  0.131  0.943  1.0
  O  O20  1  0.456  0.094  0.686  1.0
  O  O21  1  0.094  0.456  0.314  1.0
  O  O22  1  0.544  0.906  0.186  1.0
  O  O23  1  0.906  0.544  0.814  1.0
  O  O24  1  0.907  0.093  0.750  1.0
  O  O25  1  0.093  0.907  0.250  1.0
[/CIF]
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