The crystal structure described by Na2AsP(H4O5)2 crystallizes in the monoclinic P2_1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(2), one O(3), one O(5), one O(6), one O(7), and one O(9) atom to form distorted NaO6 octahedra that share corners with two equivalent Na(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and corners with three equivalent As(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 57-58°. In the second Na site, Na(2) is bonded to one O(1), one O(10), one O(4), one O(5), one O(6), and one O(8) atom to form distorted NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra,  a cornercorner with one As(1)O4 tetrahedra, and corners with three equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 57-58°. As(1) is bonded to one O(1), one O(3), one O(7), and one O(9) atom to form AsO4 tetrahedra that share  a cornercorner with one Na(2)O6 octahedra and corners with three equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 41-65°. P(1) is bonded to one O(10), one O(2), one O(4), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Na(1)O6 octahedra and corners with three equivalent Na(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 35-61°. There are eight inequivalent H sites. In the first H site, H(1) is bonded in a distorted single-bond geometry to one O(3) and one O(8) atom. In the second H site, H(2) is bonded in a distorted single-bond geometry to one O(4) and one O(7) atom. In the third H site, H(3) is bonded in a distorted linear geometry to one O(2) and one O(9) atom. In the fourth H site, H(4) is bonded in a linear geometry to one O(1) and one O(10) atom. In the fifth H site, H(5) is bonded in a single-bond geometry to one O(5) atom. In the sixth H site, H(6) is bonded in a single-bond geometry to one O(6) atom. In the seventh H site, H(7) is bonded in a single-bond geometry to one O(5) atom. In the eighth H site, H(8) is bonded in a single-bond geometry to one O(6) atom. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Na(2), one As(1), and one H(4) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one P(1), and one H(3) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to one Na(1), one As(1), and one H(1) atom. In the fourth O site, O(4) is bonded in a distorted water-like geometry to one Na(2), one P(1), and one H(2) atom. In the fifth O site, O(5) is bonded in a distorted water-like geometry to one Na(1), one Na(2), one H(5), and one H(7) atom. In the sixth O site, O(6) is bonded in a distorted water-like geometry to one Na(1), one Na(2), one H(6), and one H(8) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one As(1), and one H(2) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Na(2), one P(1), and one H(1) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Na(1), one As(1), and one H(3) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Na(2), one P(1), and one H(4) atom. is represented by the CIF file [CIF]
data_Na2AsP(H4O5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.286
_cell_length_b   5.268
_cell_length_c   8.404
_cell_angle_alpha   89.540
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   455.346
_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  0.600  0.663  0.415  1.0
  Na  Na1  1  0.100  0.337  0.585  1.0
  Na  Na2  1  0.403  0.174  0.088  1.0
  Na  Na3  1  0.903  0.826  0.912  1.0
  As  As4  1  0.343  0.831  0.692  1.0
  As  As5  1  0.843  0.169  0.308  1.0
  P  P6  1  0.659  0.337  0.807  1.0
  P  P7  1  0.159  0.663  0.193  1.0
  H  H8  1  0.401  0.435  0.758  1.0
  H  H9  1  0.901  0.565  0.242  1.0
  H  H10  1  0.604  0.959  0.740  1.0
  H  H11  1  0.104  0.041  0.260  1.0
  H  H12  1  0.203  0.800  0.480  1.0
  H  H13  1  0.703  0.200  0.520  1.0
  H  H14  1  0.790  0.293  0.010  1.0
  H  H15  1  0.290  0.707  0.990  1.0
  H  H16  1  0.549  0.700  0.056  1.0
  H  H17  1  0.049  0.300  0.944  1.0
  H  H18  1  0.453  0.201  0.442  1.0
  H  H19  1  0.953  0.799  0.558  1.0
  H  H20  1  0.644  0.906  0.122  1.0
  H  H21  1  0.144  0.094  0.878  1.0
  H  H22  1  0.355  0.405  0.375  1.0
  H  H23  1  0.855  0.595  0.625  1.0
  O  O24  1  0.305  0.934  0.877  1.0
  O  O25  1  0.805  0.066  0.123  1.0
  O  O26  1  0.688  0.433  0.638  1.0
  O  O27  1  0.188  0.567  0.362  1.0
  O  O28  1  0.326  0.497  0.689  1.0
  O  O29  1  0.826  0.503  0.311  1.0
  O  O30  1  0.674  0.034  0.812  1.0
  O  O31  1  0.174  0.966  0.188  1.0
  O  O32  1  0.557  0.828  0.139  1.0
  O  O33  1  0.057  0.172  0.861  1.0
  O  O34  1  0.442  0.332  0.358  1.0
  O  O35  1  0.942  0.668  0.642  1.0
  O  O36  1  0.486  0.926  0.612  1.0
  O  O37  1  0.986  0.074  0.388  1.0
  O  O38  1  0.528  0.416  0.875  1.0
  O  O39  1  0.028  0.584  0.125  1.0
  O  O40  1  0.215  0.931  0.568  1.0
  O  O41  1  0.715  0.069  0.432  1.0
  O  O42  1  0.774  0.427  0.920  1.0
  O  O43  1  0.274  0.573  0.080  1.0
[/CIF]
.
The crystal structure described by Na2AsP(H4O5)2 crystallizes in the monoclinic P2_1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(2), one O(3), one O(5), one O(6), one O(7), and one O(9) atom to form distorted NaO6 octahedra that share corners with two equivalent Na(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and corners with three equivalent As(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 57-58°. In the second Na site, Na(2) is bonded to one O(1), one O(10), one O(4), one O(5), one O(6), and one O(8) atom to form distorted NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra,  a cornercorner with one As(1)O4 tetrahedra, and corners with three equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 57-58°. As(1) is bonded to one O(1), one O(3), one O(7), and one O(9) atom to form AsO4 tetrahedra that share  a cornercorner with one Na(2)O6 octahedra and corners with three equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 41-65°. P(1) is bonded to one O(10), one O(2), one O(4), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Na(1)O6 octahedra and corners with three equivalent Na(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 35-61°. There are eight inequivalent H sites. In the first H site, H(1) is bonded in a distorted single-bond geometry to one O(3) and one O(8) atom. In the second H site, H(2) is bonded in a distorted single-bond geometry to one O(4) and one O(7) atom. In the third H site, H(3) is bonded in a distorted linear geometry to one O(2) and one O(9) atom. In the fourth H site, H(4) is bonded in a linear geometry to one O(1) and one O(10) atom. In the fifth H site, H(5) is bonded in a single-bond geometry to one O(5) atom. In the sixth H site, H(6) is bonded in a single-bond geometry to one O(6) atom. In the seventh H site, H(7) is bonded in a single-bond geometry to one O(5) atom. In the eighth H site, H(8) is bonded in a single-bond geometry to one O(6) atom. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Na(2), one As(1), and one H(4) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one P(1), and one H(3) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to one Na(1), one As(1), and one H(1) atom. In the fourth O site, O(4) is bonded in a distorted water-like geometry to one Na(2), one P(1), and one H(2) atom. In the fifth O site, O(5) is bonded in a distorted water-like geometry to one Na(1), one Na(2), one H(5), and one H(7) atom. In the sixth O site, O(6) is bonded in a distorted water-like geometry to one Na(1), one Na(2), one H(6), and one H(8) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one As(1), and one H(2) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Na(2), one P(1), and one H(1) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Na(1), one As(1), and one H(3) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Na(2), one P(1), and one H(4) atom. is represented by the CIF file [CIF]
data_Na2AsP(H4O5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.286
_cell_length_b   5.268
_cell_length_c   8.404
_cell_angle_alpha   89.540
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   455.346
_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  0.600  0.663  0.415  1.0
  Na  Na1  1  0.100  0.337  0.585  1.0
  Na  Na2  1  0.403  0.174  0.088  1.0
  Na  Na3  1  0.903  0.826  0.912  1.0
  As  As4  1  0.343  0.831  0.692  1.0
  As  As5  1  0.843  0.169  0.308  1.0
  P  P6  1  0.659  0.337  0.807  1.0
  P  P7  1  0.159  0.663  0.193  1.0
  H  H8  1  0.401  0.435  0.758  1.0
  H  H9  1  0.901  0.565  0.242  1.0
  H  H10  1  0.604  0.959  0.740  1.0
  H  H11  1  0.104  0.041  0.260  1.0
  H  H12  1  0.203  0.800  0.480  1.0
  H  H13  1  0.703  0.200  0.520  1.0
  H  H14  1  0.790  0.293  0.010  1.0
  H  H15  1  0.290  0.707  0.990  1.0
  H  H16  1  0.549  0.700  0.056  1.0
  H  H17  1  0.049  0.300  0.944  1.0
  H  H18  1  0.453  0.201  0.442  1.0
  H  H19  1  0.953  0.799  0.558  1.0
  H  H20  1  0.644  0.906  0.122  1.0
  H  H21  1  0.144  0.094  0.878  1.0
  H  H22  1  0.355  0.405  0.375  1.0
  H  H23  1  0.855  0.595  0.625  1.0
  O  O24  1  0.305  0.934  0.877  1.0
  O  O25  1  0.805  0.066  0.123  1.0
  O  O26  1  0.688  0.433  0.638  1.0
  O  O27  1  0.188  0.567  0.362  1.0
  O  O28  1  0.326  0.497  0.689  1.0
  O  O29  1  0.826  0.503  0.311  1.0
  O  O30  1  0.674  0.034  0.812  1.0
  O  O31  1  0.174  0.966  0.188  1.0
  O  O32  1  0.557  0.828  0.139  1.0
  O  O33  1  0.057  0.172  0.861  1.0
  O  O34  1  0.442  0.332  0.358  1.0
  O  O35  1  0.942  0.668  0.642  1.0
  O  O36  1  0.486  0.926  0.612  1.0
  O  O37  1  0.986  0.074  0.388  1.0
  O  O38  1  0.528  0.416  0.875  1.0
  O  O39  1  0.028  0.584  0.125  1.0
  O  O40  1  0.215  0.931  0.568  1.0
  O  O41  1  0.715  0.069  0.432  1.0
  O  O42  1  0.774  0.427  0.920  1.0
  O  O43  1  0.274  0.573  0.080  1.0
[/CIF]
.