The structure described by Np2O5 crystallizes in the triclinic P-1 space group. There are three inequivalent Np sites. In the first Np site, Np(1) is bonded to one O(1), one O(2), one O(3), two equivalent O(4), and two equivalent O(5) atoms to form distorted NpO7 pentagonal bipyramids that share corners with two equivalent Np(2)O6 octahedra, corners with two equivalent Np(3)O6 octahedra,  an edgeedge with one Np(2)O6 octahedra,  an edgeedge with one Np(3)O6 octahedra, and edges with two equivalent Np(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 5-38°. In the second Np site, Np(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form NpO6 octahedra that share corners with two equivalent Np(3)O6 octahedra, corners with four equivalent Np(1)O7 pentagonal bipyramids, and edges with two equivalent Np(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 37°. In the third Np site, Np(3) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(5) atoms to form NpO6 octahedra that share corners with two equivalent Np(2)O6 octahedra, corners with four equivalent Np(1)O7 pentagonal bipyramids, and edges with two equivalent Np(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 37°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Np(1), one Np(2), and one Np(3) atom. In the second O site, O(2) is bonded in a linear geometry to one Np(1) and one Np(3) atom. In the third O site, O(3) is bonded in a linear geometry to one Np(1) and one Np(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Np(2) and two equivalent Np(1) atoms. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Np(3) and two equivalent Np(1) atoms. is represented by the CIF card [CIF]
data_Np2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.700
_cell_length_b   5.724
_cell_length_c   8.054
_cell_angle_alpha   97.252
_cell_angle_beta   110.380
_cell_angle_gamma   109.120
_symmetry_Int_Tables_number   1
_cell_volume   223.997
_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
  Np  Np0  1  0.290  0.539  0.250  1.0
  Np  Np1  1  0.500  1.000  0.000  1.0
  Np  Np2  1  0.000  1.000  0.500  1.0
  Np  Np3  1  0.710  0.461  0.750  1.0
  O  O4  1  0.353  0.100  0.749  1.0
  O  O5  1  0.834  0.241  0.643  1.0
  O  O6  1  0.166  0.759  0.357  1.0
  O  O7  1  0.403  0.309  0.142  1.0
  O  O8  1  0.647  0.900  0.251  1.0
  O  O9  1  0.597  0.691  0.858  1.0
  O  O10  1  0.841  0.286  0.034  1.0
  O  O11  1  0.748  0.694  0.534  1.0
  O  O12  1  0.159  0.714  0.966  1.0
  O  O13  1  0.252  0.306  0.466  1.0
[/CIF]
.
The structure described by Np2O5 crystallizes in the triclinic P-1 space group. There are three inequivalent Np sites. In the first Np site, Np(1) is bonded to one O(1), one O(2), one O(3), two equivalent O(4), and two equivalent O(5) atoms to form distorted NpO7 pentagonal bipyramids that share corners with two equivalent Np(2)O6 octahedra, corners with two equivalent Np(3)O6 octahedra,  an edgeedge with one Np(2)O6 octahedra,  an edgeedge with one Np(3)O6 octahedra, and edges with two equivalent Np(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 5-38°. In the second Np site, Np(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form NpO6 octahedra that share corners with two equivalent Np(3)O6 octahedra, corners with four equivalent Np(1)O7 pentagonal bipyramids, and edges with two equivalent Np(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 37°. In the third Np site, Np(3) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(5) atoms to form NpO6 octahedra that share corners with two equivalent Np(2)O6 octahedra, corners with four equivalent Np(1)O7 pentagonal bipyramids, and edges with two equivalent Np(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 37°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Np(1), one Np(2), and one Np(3) atom. In the second O site, O(2) is bonded in a linear geometry to one Np(1) and one Np(3) atom. In the third O site, O(3) is bonded in a linear geometry to one Np(1) and one Np(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Np(2) and two equivalent Np(1) atoms. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Np(3) and two equivalent Np(1) atoms. is represented by the CIF card [CIF]
data_Np2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.700
_cell_length_b   5.724
_cell_length_c   8.054
_cell_angle_alpha   97.252
_cell_angle_beta   110.380
_cell_angle_gamma   109.120
_symmetry_Int_Tables_number   1
_cell_volume   223.997
_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
  Np  Np0  1  0.290  0.539  0.250  1.0
  Np  Np1  1  0.500  1.000  0.000  1.0
  Np  Np2  1  0.000  1.000  0.500  1.0
  Np  Np3  1  0.710  0.461  0.750  1.0
  O  O4  1  0.353  0.100  0.749  1.0
  O  O5  1  0.834  0.241  0.643  1.0
  O  O6  1  0.166  0.759  0.357  1.0
  O  O7  1  0.403  0.309  0.142  1.0
  O  O8  1  0.647  0.900  0.251  1.0
  O  O9  1  0.597  0.691  0.858  1.0
  O  O10  1  0.841  0.286  0.034  1.0
  O  O11  1  0.748  0.694  0.534  1.0
  O  O12  1  0.159  0.714  0.966  1.0
  O  O13  1  0.252  0.306  0.466  1.0
[/CIF]
.