The material described by Na2VP2O8 crystallizes in the tetragonal P4bm space group. Na(1) is bonded in a 8-coordinate geometry to one O(1), three equivalent O(4), and four equivalent O(2) atoms. V(1) is bonded in a 5-coordinate geometry to one O(3) and four equivalent O(2) atoms. P(1) is bonded to one O(1), one O(4), and two equivalent O(2) atoms to form corner-sharing PO4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to two equivalent Na(1) and two equivalent P(1) atoms. In the second O site, O(2) is bonded in a 2-coordinate geometry to two equivalent Na(1), one V(1), and one P(1) atom. In the third O site, O(3) is bonded in a single-bond geometry to one V(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to three equivalent Na(1) and one P(1) atom. is represented by the CIF file [CIF]
data_Na2V(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.351
_cell_length_b   8.351
_cell_length_c   5.024
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   350.368
_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  0.176  0.324  0.511  1.0
  Na  Na1  1  0.324  0.824  0.511  1.0
  Na  Na2  1  0.824  0.676  0.511  1.0
  Na  Na3  1  0.676  0.176  0.511  1.0
  V  V4  1  0.500  0.500  0.958  1.0
  V  V5  1  0.000  0.000  0.958  1.0
  P  P6  1  0.871  0.371  0.975  1.0
  P  P7  1  0.371  0.129  0.975  1.0
  P  P8  1  0.629  0.871  0.975  1.0
  P  P9  1  0.129  0.629  0.975  1.0
  O  O10  1  0.500  0.000  0.855  1.0
  O  O11  1  0.000  0.500  0.855  1.0
  O  O12  1  0.214  0.077  0.838  1.0
  O  O13  1  0.786  0.923  0.838  1.0
  O  O14  1  0.923  0.214  0.838  1.0
  O  O15  1  0.077  0.786  0.838  1.0
  O  O16  1  0.423  0.286  0.838  1.0
  O  O17  1  0.286  0.577  0.838  1.0
  O  O18  1  0.714  0.423  0.838  1.0
  O  O19  1  0.577  0.714  0.838  1.0
  O  O20  1  0.500  0.500  0.283  1.0
  O  O21  1  0.000  0.000  0.283  1.0
  O  O22  1  0.129  0.629  0.273  1.0
  O  O23  1  0.629  0.871  0.273  1.0
  O  O24  1  0.371  0.129  0.273  1.0
  O  O25  1  0.871  0.371  0.273  1.0
[/CIF]
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The material described by Na2VP2O8 crystallizes in the tetragonal P4bm space group. Na(1) is bonded in a 8-coordinate geometry to one O(1), three equivalent O(4), and four equivalent O(2) atoms. V(1) is bonded in a 5-coordinate geometry to one O(3) and four equivalent O(2) atoms. P(1) is bonded to one O(1), one O(4), and two equivalent O(2) atoms to form corner-sharing PO4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to two equivalent Na(1) and two equivalent P(1) atoms. In the second O site, O(2) is bonded in a 2-coordinate geometry to two equivalent Na(1), one V(1), and one P(1) atom. In the third O site, O(3) is bonded in a single-bond geometry to one V(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to three equivalent Na(1) and one P(1) atom. is represented by the CIF file [CIF]
data_Na2V(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.351
_cell_length_b   8.351
_cell_length_c   5.024
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   350.368
_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  0.176  0.324  0.511  1.0
  Na  Na1  1  0.324  0.824  0.511  1.0
  Na  Na2  1  0.824  0.676  0.511  1.0
  Na  Na3  1  0.676  0.176  0.511  1.0
  V  V4  1  0.500  0.500  0.958  1.0
  V  V5  1  0.000  0.000  0.958  1.0
  P  P6  1  0.871  0.371  0.975  1.0
  P  P7  1  0.371  0.129  0.975  1.0
  P  P8  1  0.629  0.871  0.975  1.0
  P  P9  1  0.129  0.629  0.975  1.0
  O  O10  1  0.500  0.000  0.855  1.0
  O  O11  1  0.000  0.500  0.855  1.0
  O  O12  1  0.214  0.077  0.838  1.0
  O  O13  1  0.786  0.923  0.838  1.0
  O  O14  1  0.923  0.214  0.838  1.0
  O  O15  1  0.077  0.786  0.838  1.0
  O  O16  1  0.423  0.286  0.838  1.0
  O  O17  1  0.286  0.577  0.838  1.0
  O  O18  1  0.714  0.423  0.838  1.0
  O  O19  1  0.577  0.714  0.838  1.0
  O  O20  1  0.500  0.500  0.283  1.0
  O  O21  1  0.000  0.000  0.283  1.0
  O  O22  1  0.129  0.629  0.273  1.0
  O  O23  1  0.629  0.871  0.273  1.0
  O  O24  1  0.371  0.129  0.273  1.0
  O  O25  1  0.871  0.371  0.273  1.0
[/CIF]
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