The crystal structure described by Na2ZnH4(SO4)2 crystallizes in the monoclinic P2_1/c space group. Na(1) is bonded to one O(1), one O(2), and two equivalent O(4) atoms to form distorted NaO4 tetrahedra that share corners with four equivalent S(1)O4 tetrahedra and  an edgeedge with one Na(1)O4 tetrahedra. Zn(1) is bonded in a distorted linear geometry to two equivalent H(2) and two equivalent O(3) atoms. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one H(2) atom. In the second H site, H(2) is bonded in a distorted single-bond geometry to one Zn(1) and one H(1) atom. S(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SO4 tetrahedra that share 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 distorted bent 150 degrees geometry to one Na(1) and one S(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Na(1) and one S(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Zn(1) and one S(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to two equivalent Na(1) and one S(1) atom. is represented by the CIF file [CIF]
data_Na2ZnH4(SO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.510
_cell_length_b   8.306
_cell_length_c   11.206
_cell_angle_alpha   90.000
_cell_angle_beta   110.748
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   479.582
_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  0.167  0.031  0.377  1.0
  Na  Na1  1  0.833  0.969  0.623  1.0
  Na  Na2  1  0.833  0.531  0.123  1.0
  Na  Na3  1  0.167  0.469  0.877  1.0
  Zn  Zn4  1  0.000  0.000  0.000  1.0
  Zn  Zn5  1  0.000  0.500  0.500  1.0
  H  H6  1  0.269  0.607  0.424  1.0
  H  H7  1  0.731  0.393  0.576  1.0
  H  H8  1  0.731  0.107  0.076  1.0
  H  H9  1  0.269  0.893  0.924  1.0
  H  H10  1  0.256  0.831  0.971  1.0
  H  H11  1  0.744  0.169  0.029  1.0
  H  H12  1  0.744  0.331  0.529  1.0
  H  H13  1  0.256  0.669  0.471  1.0
  S  S14  1  0.338  0.275  0.165  1.0
  S  S15  1  0.662  0.725  0.835  1.0
  S  S16  1  0.662  0.775  0.335  1.0
  S  S17  1  0.338  0.225  0.665  1.0
  O  O18  1  0.277  0.249  0.281  1.0
  O  O19  1  0.723  0.751  0.719  1.0
  O  O20  1  0.723  0.749  0.219  1.0
  O  O21  1  0.277  0.251  0.781  1.0
  O  O22  1  0.609  0.322  0.192  1.0
  O  O23  1  0.391  0.678  0.808  1.0
  O  O24  1  0.391  0.822  0.308  1.0
  O  O25  1  0.609  0.178  0.692  1.0
  O  O26  1  0.301  0.112  0.091  1.0
  O  O27  1  0.699  0.888  0.909  1.0
  O  O28  1  0.699  0.612  0.409  1.0
  O  O29  1  0.301  0.388  0.591  1.0
  O  O30  1  0.156  0.392  0.078  1.0
  O  O31  1  0.844  0.608  0.922  1.0
  O  O32  1  0.844  0.892  0.422  1.0
  O  O33  1  0.156  0.108  0.578  1.0
[/CIF]
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The crystal structure described by Na2ZnH4(SO4)2 crystallizes in the monoclinic P2_1/c space group. Na(1) is bonded to one O(1), one O(2), and two equivalent O(4) atoms to form distorted NaO4 tetrahedra that share corners with four equivalent S(1)O4 tetrahedra and  an edgeedge with one Na(1)O4 tetrahedra. Zn(1) is bonded in a distorted linear geometry to two equivalent H(2) and two equivalent O(3) atoms. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one H(2) atom. In the second H site, H(2) is bonded in a distorted single-bond geometry to one Zn(1) and one H(1) atom. S(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SO4 tetrahedra that share 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 distorted bent 150 degrees geometry to one Na(1) and one S(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Na(1) and one S(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Zn(1) and one S(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to two equivalent Na(1) and one S(1) atom. is represented by the CIF file [CIF]
data_Na2ZnH4(SO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.510
_cell_length_b   8.306
_cell_length_c   11.206
_cell_angle_alpha   90.000
_cell_angle_beta   110.748
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   479.582
_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  0.167  0.031  0.377  1.0
  Na  Na1  1  0.833  0.969  0.623  1.0
  Na  Na2  1  0.833  0.531  0.123  1.0
  Na  Na3  1  0.167  0.469  0.877  1.0
  Zn  Zn4  1  0.000  0.000  0.000  1.0
  Zn  Zn5  1  0.000  0.500  0.500  1.0
  H  H6  1  0.269  0.607  0.424  1.0
  H  H7  1  0.731  0.393  0.576  1.0
  H  H8  1  0.731  0.107  0.076  1.0
  H  H9  1  0.269  0.893  0.924  1.0
  H  H10  1  0.256  0.831  0.971  1.0
  H  H11  1  0.744  0.169  0.029  1.0
  H  H12  1  0.744  0.331  0.529  1.0
  H  H13  1  0.256  0.669  0.471  1.0
  S  S14  1  0.338  0.275  0.165  1.0
  S  S15  1  0.662  0.725  0.835  1.0
  S  S16  1  0.662  0.775  0.335  1.0
  S  S17  1  0.338  0.225  0.665  1.0
  O  O18  1  0.277  0.249  0.281  1.0
  O  O19  1  0.723  0.751  0.719  1.0
  O  O20  1  0.723  0.749  0.219  1.0
  O  O21  1  0.277  0.251  0.781  1.0
  O  O22  1  0.609  0.322  0.192  1.0
  O  O23  1  0.391  0.678  0.808  1.0
  O  O24  1  0.391  0.822  0.308  1.0
  O  O25  1  0.609  0.178  0.692  1.0
  O  O26  1  0.301  0.112  0.091  1.0
  O  O27  1  0.699  0.888  0.909  1.0
  O  O28  1  0.699  0.612  0.409  1.0
  O  O29  1  0.301  0.388  0.591  1.0
  O  O30  1  0.156  0.392  0.078  1.0
  O  O31  1  0.844  0.608  0.922  1.0
  O  O32  1  0.844  0.892  0.422  1.0
  O  O33  1  0.156  0.108  0.578  1.0
[/CIF]
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