The material described by Na2CuH4(SO5)2 crystallizes in the monoclinic P2_1/c space group. Na(1) is bonded to one O(1), one O(3), one O(5), two equivalent O(2), and two equivalent O(4) atoms to form distorted NaO7 pentagonal bipyramids that share corners with two equivalent Na(1)O7 pentagonal bipyramids, corners with four equivalent S(1)O4 tetrahedra, edges with two equivalent Cu(1)O6 octahedra,  an edgeedge with one Na(1)O7 pentagonal bipyramid, and  an edgeedge with one S(1)O4 tetrahedra. Cu(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form CuO6 octahedra that share corners with four equivalent S(1)O4 tetrahedra and edges with four equivalent Na(1)O7 pentagonal bipyramids. There are two inequivalent H sites. In the first H site, H(1) is bonded in a distorted single-bond geometry to one O(1) and one O(5) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(4) and one O(5) 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 two equivalent Cu(1)O6 octahedra, corners with four equivalent Na(1)O7 pentagonal bipyramids, and  an edgeedge with one Na(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 41-52°. There are five inequivalent O sites. In the first O site, O(5) is bonded in a distorted water-like geometry to one Na(1), one Cu(1), one H(1), and one H(2) atom. In the second O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one H(1), and one S(1) atom. In the third O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Cu(1), and one S(1) atom. In the fourth O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one Cu(1), and one S(1) atom. In the fifth O site, O(4) is bonded to two equivalent Na(1), one H(2), and one S(1) atom to form distorted corner-sharing ONa2HS trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2CuH4(SO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.833
_cell_length_b   5.641
_cell_length_c   5.881
_cell_angle_alpha   70.279
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   400.725
_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  0.624  0.288  0.569  1.0
  Na  Na1  1  0.124  0.212  0.431  1.0
  Na  Na2  1  0.376  0.712  0.431  1.0
  Na  Na3  1  0.876  0.788  0.569  1.0
  Cu  Cu4  1  0.500  0.500  0.000  1.0
  Cu  Cu5  1  0.000  0.000  0.000  1.0
  H  H6  1  0.699  0.516  0.928  1.0
  H  H7  1  0.199  0.984  0.072  1.0
  H  H8  1  0.301  0.484  0.072  1.0
  H  H9  1  0.801  0.016  0.928  1.0
  H  H10  1  0.645  0.716  0.702  1.0
  H  H11  1  0.145  0.784  0.298  1.0
  H  H12  1  0.355  0.284  0.298  1.0
  H  H13  1  0.855  0.216  0.702  1.0
  S  S14  1  0.619  0.955  0.240  1.0
  S  S15  1  0.119  0.545  0.760  1.0
  S  S16  1  0.381  0.045  0.760  1.0
  S  S17  1  0.881  0.455  0.240  1.0
  O  O18  1  0.676  0.014  0.009  1.0
  O  O19  1  0.176  0.486  0.991  1.0
  O  O20  1  0.324  0.986  0.991  1.0
  O  O21  1  0.824  0.514  0.009  1.0
  O  O22  1  0.558  0.719  0.293  1.0
  O  O23  1  0.058  0.781  0.707  1.0
  O  O24  1  0.442  0.281  0.707  1.0
  O  O25  1  0.942  0.219  0.293  1.0
  O  O26  1  0.545  0.168  0.232  1.0
  O  O27  1  0.045  0.332  0.768  1.0
  O  O28  1  0.455  0.832  0.768  1.0
  O  O29  1  0.955  0.668  0.232  1.0
  O  O30  1  0.692  0.934  0.446  1.0
  O  O31  1  0.192  0.566  0.554  1.0
  O  O32  1  0.308  0.066  0.554  1.0
  O  O33  1  0.808  0.434  0.446  1.0
  O  O34  1  0.634  0.547  0.828  1.0
  O  O35  1  0.134  0.953  0.172  1.0
  O  O36  1  0.366  0.453  0.172  1.0
  O  O37  1  0.866  0.047  0.828  1.0
[/CIF]
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The material described by Na2CuH4(SO5)2 crystallizes in the monoclinic P2_1/c space group. Na(1) is bonded to one O(1), one O(3), one O(5), two equivalent O(2), and two equivalent O(4) atoms to form distorted NaO7 pentagonal bipyramids that share corners with two equivalent Na(1)O7 pentagonal bipyramids, corners with four equivalent S(1)O4 tetrahedra, edges with two equivalent Cu(1)O6 octahedra,  an edgeedge with one Na(1)O7 pentagonal bipyramid, and  an edgeedge with one S(1)O4 tetrahedra. Cu(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form CuO6 octahedra that share corners with four equivalent S(1)O4 tetrahedra and edges with four equivalent Na(1)O7 pentagonal bipyramids. There are two inequivalent H sites. In the first H site, H(1) is bonded in a distorted single-bond geometry to one O(1) and one O(5) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(4) and one O(5) 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 two equivalent Cu(1)O6 octahedra, corners with four equivalent Na(1)O7 pentagonal bipyramids, and  an edgeedge with one Na(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 41-52°. There are five inequivalent O sites. In the first O site, O(5) is bonded in a distorted water-like geometry to one Na(1), one Cu(1), one H(1), and one H(2) atom. In the second O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one H(1), and one S(1) atom. In the third O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Cu(1), and one S(1) atom. In the fourth O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one Cu(1), and one S(1) atom. In the fifth O site, O(4) is bonded to two equivalent Na(1), one H(2), and one S(1) atom to form distorted corner-sharing ONa2HS trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2CuH4(SO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.833
_cell_length_b   5.641
_cell_length_c   5.881
_cell_angle_alpha   70.279
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   400.725
_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  0.624  0.288  0.569  1.0
  Na  Na1  1  0.124  0.212  0.431  1.0
  Na  Na2  1  0.376  0.712  0.431  1.0
  Na  Na3  1  0.876  0.788  0.569  1.0
  Cu  Cu4  1  0.500  0.500  0.000  1.0
  Cu  Cu5  1  0.000  0.000  0.000  1.0
  H  H6  1  0.699  0.516  0.928  1.0
  H  H7  1  0.199  0.984  0.072  1.0
  H  H8  1  0.301  0.484  0.072  1.0
  H  H9  1  0.801  0.016  0.928  1.0
  H  H10  1  0.645  0.716  0.702  1.0
  H  H11  1  0.145  0.784  0.298  1.0
  H  H12  1  0.355  0.284  0.298  1.0
  H  H13  1  0.855  0.216  0.702  1.0
  S  S14  1  0.619  0.955  0.240  1.0
  S  S15  1  0.119  0.545  0.760  1.0
  S  S16  1  0.381  0.045  0.760  1.0
  S  S17  1  0.881  0.455  0.240  1.0
  O  O18  1  0.676  0.014  0.009  1.0
  O  O19  1  0.176  0.486  0.991  1.0
  O  O20  1  0.324  0.986  0.991  1.0
  O  O21  1  0.824  0.514  0.009  1.0
  O  O22  1  0.558  0.719  0.293  1.0
  O  O23  1  0.058  0.781  0.707  1.0
  O  O24  1  0.442  0.281  0.707  1.0
  O  O25  1  0.942  0.219  0.293  1.0
  O  O26  1  0.545  0.168  0.232  1.0
  O  O27  1  0.045  0.332  0.768  1.0
  O  O28  1  0.455  0.832  0.768  1.0
  O  O29  1  0.955  0.668  0.232  1.0
  O  O30  1  0.692  0.934  0.446  1.0
  O  O31  1  0.192  0.566  0.554  1.0
  O  O32  1  0.308  0.066  0.554  1.0
  O  O33  1  0.808  0.434  0.446  1.0
  O  O34  1  0.634  0.547  0.828  1.0
  O  O35  1  0.134  0.953  0.172  1.0
  O  O36  1  0.366  0.453  0.172  1.0
  O  O37  1  0.866  0.047  0.828  1.0
[/CIF]
.