The compound described by Na2Al(P2O7)2 crystallizes in the triclinic P-1 space group. Na(1) is bonded in a 6-coordinate geometry to one O(1), one O(3), one O(6), one O(7), and two equivalent O(5) atoms. Al(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form AlO6 octahedra that share corners with two equivalent P(2)O4 tetrahedra and corners with four equivalent P(1)O4 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form PO4 tetrahedra that share corners with two equivalent Al(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 42-43°. In the second P site, P(2) is bonded to one O(2), one O(4), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Al(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 42°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Al(1), and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Al(1) and one P(2) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Na(1), one Al(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one P(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to two equivalent Na(1) and one P(1) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Na(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Na(1) and one P(2) atom. is represented by the CIF file [CIF]
data_Na2Al(P2O7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.953
_cell_length_b   7.549
_cell_length_c   8.347
_cell_angle_alpha   65.988
_cell_angle_beta   81.354
_cell_angle_gamma   80.844
_symmetry_Int_Tables_number   1
_cell_volume   280.208
_cell_formula_units_Z   1
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  0.100  0.780  0.711  1.0
  Na  Na1  1  0.900  0.220  0.289  1.0
  Al  Al2  1  0.000  0.000  0.000  1.0
  P  P3  1  0.551  0.079  0.735  1.0
  P  P4  1  0.449  0.921  0.265  1.0
  P  P5  1  0.715  0.423  0.772  1.0
  P  P6  1  0.285  0.577  0.228  1.0
  O  O7  1  0.253  0.039  0.792  1.0
  O  O8  1  0.747  0.961  0.208  1.0
  O  O9  1  0.878  0.271  0.918  1.0
  O  O10  1  0.122  0.729  0.082  1.0
  O  O11  1  0.743  0.957  0.879  1.0
  O  O12  1  0.257  0.043  0.121  1.0
  O  O13  1  0.560  0.308  0.692  1.0
  O  O14  1  0.440  0.692  0.308  1.0
  O  O15  1  0.666  0.047  0.567  1.0
  O  O16  1  0.334  0.953  0.433  1.0
  O  O17  1  0.886  0.570  0.625  1.0
  O  O18  1  0.114  0.430  0.375  1.0
  O  O19  1  0.497  0.563  0.824  1.0
  O  O20  1  0.503  0.437  0.176  1.0
[/CIF]
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The compound described by Na2Al(P2O7)2 crystallizes in the triclinic P-1 space group. Na(1) is bonded in a 6-coordinate geometry to one O(1), one O(3), one O(6), one O(7), and two equivalent O(5) atoms. Al(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form AlO6 octahedra that share corners with two equivalent P(2)O4 tetrahedra and corners with four equivalent P(1)O4 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form PO4 tetrahedra that share corners with two equivalent Al(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 42-43°. In the second P site, P(2) is bonded to one O(2), one O(4), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Al(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 42°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Al(1), and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Al(1) and one P(2) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Na(1), one Al(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one P(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to two equivalent Na(1) and one P(1) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Na(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Na(1) and one P(2) atom. is represented by the CIF file [CIF]
data_Na2Al(P2O7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.953
_cell_length_b   7.549
_cell_length_c   8.347
_cell_angle_alpha   65.988
_cell_angle_beta   81.354
_cell_angle_gamma   80.844
_symmetry_Int_Tables_number   1
_cell_volume   280.208
_cell_formula_units_Z   1
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  0.100  0.780  0.711  1.0
  Na  Na1  1  0.900  0.220  0.289  1.0
  Al  Al2  1  0.000  0.000  0.000  1.0
  P  P3  1  0.551  0.079  0.735  1.0
  P  P4  1  0.449  0.921  0.265  1.0
  P  P5  1  0.715  0.423  0.772  1.0
  P  P6  1  0.285  0.577  0.228  1.0
  O  O7  1  0.253  0.039  0.792  1.0
  O  O8  1  0.747  0.961  0.208  1.0
  O  O9  1  0.878  0.271  0.918  1.0
  O  O10  1  0.122  0.729  0.082  1.0
  O  O11  1  0.743  0.957  0.879  1.0
  O  O12  1  0.257  0.043  0.121  1.0
  O  O13  1  0.560  0.308  0.692  1.0
  O  O14  1  0.440  0.692  0.308  1.0
  O  O15  1  0.666  0.047  0.567  1.0
  O  O16  1  0.334  0.953  0.433  1.0
  O  O17  1  0.886  0.570  0.625  1.0
  O  O18  1  0.114  0.430  0.375  1.0
  O  O19  1  0.497  0.563  0.824  1.0
  O  O20  1  0.503  0.437  0.176  1.0
[/CIF]
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