The structure described by Na3NpH2Se2O11 crystallizes in the triclinic P-1 space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(3), one O(4), one O(5), one O(9), and two equivalent O(1) atoms. In the second Na site, Na(2) is bonded to one O(3), one O(5), one O(6), one O(8), and two equivalent O(2) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(3)O7 pentagonal bipyramid,  a cornercorner with one Np(1)O7 pentagonal bipyramid,  a cornercorner with one Se(2)O4 tetrahedra, corners with three equivalent Se(1)O4 tetrahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Np(1)O7 pentagonal bipyramid, and edges with two equivalent Na(3)O7 pentagonal bipyramids. In the third Na site, Na(3) is bonded to one O(10), one O(11), one O(2), one O(3), one O(7), and two equivalent O(8) atoms to form distorted NaO7 pentagonal bipyramids that share  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Se(2)O4 tetrahedra, edges with two equivalent Na(2)O6 octahedra,  an edgeedge with one Na(3)O7 pentagonal bipyramid, edges with two equivalent Np(1)O7 pentagonal bipyramids, and edges with two equivalent Se(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 59°. Np(1) is bonded to one O(1), one O(10), one O(11), one O(2), one O(4), one O(6), and one O(7) atom to form distorted NpO7 pentagonal bipyramids that share  a cornercorner with one Na(2)O6 octahedra, corners with two equivalent Se(1)O4 tetrahedra, corners with two equivalent Se(2)O4 tetrahedra,  an edgeedge with one Na(2)O6 octahedra, and edges with two equivalent Na(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 53°. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(7) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(7) atom. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one O(11), one O(3), one O(6), and one O(8) atom to form SeO4 tetrahedra that share corners with three equivalent Na(2)O6 octahedra, corners with two equivalent Np(1)O7 pentagonal bipyramids, and edges with two equivalent Na(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 45-56°. In the second Se site, Se(2) is bonded to one O(10), one O(4), one O(5), and one O(9) atom to form SeO4 tetrahedra that share  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Na(3)O7 pentagonal bipyramid, and corners with two equivalent Np(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 60°. There are eleven inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Na(1) and one Np(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Na(3), two equivalent Na(2), and one Np(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Na(3), and one Se(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Na(1), one Np(1), and one Se(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Na(1), one Na(2), and one Se(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Na(2), one Np(1), and one Se(1) atom. In the seventh O site, O(7) is bonded in a water-like geometry to one Na(3), one Np(1), one H(1), and one H(2) atom. In the eighth O site, O(8) is bonded to one Na(2), two equivalent Na(3), and one Se(1) atom to form distorted edge-sharing ONa3Se trigonal pyramids. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one Na(1) and one Se(2) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Na(3), one Np(1), and one Se(2) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Na(3), one Np(1), and one Se(1) atom. is represented by the CIF card [CIF]
data_Na3NpH2Se2O11
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.143
_cell_length_b   8.156
_cell_length_c   9.894
_cell_angle_alpha   89.160
_cell_angle_beta   95.919
_cell_angle_gamma   111.824
_symmetry_Int_Tables_number   1
_cell_volume   532.054
_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  0.888  0.275  0.601  1.0
  Na  Na1  1  0.112  0.725  0.399  1.0
  Na  Na2  1  0.842  0.788  0.091  1.0
  Na  Na3  1  0.158  0.212  0.909  1.0
  Na  Na4  1  0.536  0.918  0.818  1.0
  Na  Na5  1  0.464  0.082  0.182  1.0
  Np  Np6  1  0.913  0.729  0.742  1.0
  Np  Np7  1  0.087  0.271  0.258  1.0
  H  H8  1  0.483  0.675  0.595  1.0
  H  H9  1  0.517  0.325  0.405  1.0
  H  H10  1  0.434  0.514  0.693  1.0
  H  H11  1  0.566  0.486  0.307  1.0
  Se  Se12  1  0.719  0.315  0.952  1.0
  Se  Se13  1  0.281  0.685  0.048  1.0
  Se  Se14  1  0.705  0.871  0.413  1.0
  Se  Se15  1  0.295  0.129  0.587  1.0
  O  O16  1  0.925  0.574  0.613  1.0
  O  O17  1  0.075  0.426  0.387  1.0
  O  O18  1  0.902  0.893  0.865  1.0
  O  O19  1  0.098  0.107  0.135  1.0
  O  O20  1  0.840  0.238  0.849  1.0
  O  O21  1  0.160  0.762  0.151  1.0
  O  O22  1  0.822  0.920  0.573  1.0
  O  O23  1  0.178  0.080  0.427  1.0
  O  O24  1  0.786  0.738  0.330  1.0
  O  O25  1  0.214  0.262  0.670  1.0
  O  O26  1  0.736  0.521  0.912  1.0
  O  O27  1  0.264  0.479  0.088  1.0
  O  O28  1  0.522  0.638  0.686  1.0
  O  O29  1  0.478  0.362  0.314  1.0
  O  O30  1  0.477  0.178  0.943  1.0
  O  O31  1  0.523  0.822  0.057  1.0
  O  O32  1  0.459  0.773  0.427  1.0
  O  O33  1  0.541  0.227  0.573  1.0
  O  O34  1  0.247  0.935  0.666  1.0
  O  O35  1  0.753  0.065  0.334  1.0
  O  O36  1  0.188  0.680  0.884  1.0
  O  O37  1  0.812  0.320  0.116  1.0
[/CIF]
.
The structure described by Na3NpH2Se2O11 crystallizes in the triclinic P-1 space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(3), one O(4), one O(5), one O(9), and two equivalent O(1) atoms. In the second Na site, Na(2) is bonded to one O(3), one O(5), one O(6), one O(8), and two equivalent O(2) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(3)O7 pentagonal bipyramid,  a cornercorner with one Np(1)O7 pentagonal bipyramid,  a cornercorner with one Se(2)O4 tetrahedra, corners with three equivalent Se(1)O4 tetrahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Np(1)O7 pentagonal bipyramid, and edges with two equivalent Na(3)O7 pentagonal bipyramids. In the third Na site, Na(3) is bonded to one O(10), one O(11), one O(2), one O(3), one O(7), and two equivalent O(8) atoms to form distorted NaO7 pentagonal bipyramids that share  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Se(2)O4 tetrahedra, edges with two equivalent Na(2)O6 octahedra,  an edgeedge with one Na(3)O7 pentagonal bipyramid, edges with two equivalent Np(1)O7 pentagonal bipyramids, and edges with two equivalent Se(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 59°. Np(1) is bonded to one O(1), one O(10), one O(11), one O(2), one O(4), one O(6), and one O(7) atom to form distorted NpO7 pentagonal bipyramids that share  a cornercorner with one Na(2)O6 octahedra, corners with two equivalent Se(1)O4 tetrahedra, corners with two equivalent Se(2)O4 tetrahedra,  an edgeedge with one Na(2)O6 octahedra, and edges with two equivalent Na(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 53°. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(7) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(7) atom. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one O(11), one O(3), one O(6), and one O(8) atom to form SeO4 tetrahedra that share corners with three equivalent Na(2)O6 octahedra, corners with two equivalent Np(1)O7 pentagonal bipyramids, and edges with two equivalent Na(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 45-56°. In the second Se site, Se(2) is bonded to one O(10), one O(4), one O(5), and one O(9) atom to form SeO4 tetrahedra that share  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Na(3)O7 pentagonal bipyramid, and corners with two equivalent Np(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 60°. There are eleven inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Na(1) and one Np(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Na(3), two equivalent Na(2), and one Np(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Na(3), and one Se(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Na(1), one Np(1), and one Se(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Na(1), one Na(2), and one Se(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Na(2), one Np(1), and one Se(1) atom. In the seventh O site, O(7) is bonded in a water-like geometry to one Na(3), one Np(1), one H(1), and one H(2) atom. In the eighth O site, O(8) is bonded to one Na(2), two equivalent Na(3), and one Se(1) atom to form distorted edge-sharing ONa3Se trigonal pyramids. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one Na(1) and one Se(2) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Na(3), one Np(1), and one Se(2) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Na(3), one Np(1), and one Se(1) atom. is represented by the CIF card [CIF]
data_Na3NpH2Se2O11
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.143
_cell_length_b   8.156
_cell_length_c   9.894
_cell_angle_alpha   89.160
_cell_angle_beta   95.919
_cell_angle_gamma   111.824
_symmetry_Int_Tables_number   1
_cell_volume   532.054
_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  0.888  0.275  0.601  1.0
  Na  Na1  1  0.112  0.725  0.399  1.0
  Na  Na2  1  0.842  0.788  0.091  1.0
  Na  Na3  1  0.158  0.212  0.909  1.0
  Na  Na4  1  0.536  0.918  0.818  1.0
  Na  Na5  1  0.464  0.082  0.182  1.0
  Np  Np6  1  0.913  0.729  0.742  1.0
  Np  Np7  1  0.087  0.271  0.258  1.0
  H  H8  1  0.483  0.675  0.595  1.0
  H  H9  1  0.517  0.325  0.405  1.0
  H  H10  1  0.434  0.514  0.693  1.0
  H  H11  1  0.566  0.486  0.307  1.0
  Se  Se12  1  0.719  0.315  0.952  1.0
  Se  Se13  1  0.281  0.685  0.048  1.0
  Se  Se14  1  0.705  0.871  0.413  1.0
  Se  Se15  1  0.295  0.129  0.587  1.0
  O  O16  1  0.925  0.574  0.613  1.0
  O  O17  1  0.075  0.426  0.387  1.0
  O  O18  1  0.902  0.893  0.865  1.0
  O  O19  1  0.098  0.107  0.135  1.0
  O  O20  1  0.840  0.238  0.849  1.0
  O  O21  1  0.160  0.762  0.151  1.0
  O  O22  1  0.822  0.920  0.573  1.0
  O  O23  1  0.178  0.080  0.427  1.0
  O  O24  1  0.786  0.738  0.330  1.0
  O  O25  1  0.214  0.262  0.670  1.0
  O  O26  1  0.736  0.521  0.912  1.0
  O  O27  1  0.264  0.479  0.088  1.0
  O  O28  1  0.522  0.638  0.686  1.0
  O  O29  1  0.478  0.362  0.314  1.0
  O  O30  1  0.477  0.178  0.943  1.0
  O  O31  1  0.523  0.822  0.057  1.0
  O  O32  1  0.459  0.773  0.427  1.0
  O  O33  1  0.541  0.227  0.573  1.0
  O  O34  1  0.247  0.935  0.666  1.0
  O  O35  1  0.753  0.065  0.334  1.0
  O  O36  1  0.188  0.680  0.884  1.0
  O  O37  1  0.812  0.320  0.116  1.0
[/CIF]
.