The structure described by Rb2Np2O5 crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. In the second Rb site, Rb(2) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form RbO12 cuboctahedra that share corners with four equivalent Rb(2)O12 cuboctahedra, faces with four equivalent Rb(2)O12 cuboctahedra, and faces with eight equivalent Np(1)O5 square pyramids. Np(1) is bonded to one O(2) and four equivalent O(1) atoms to form NpO5 square pyramids that share corners with five equivalent Np(1)O5 square pyramids and faces with four equivalent Rb(2)O12 cuboctahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Rb(1), two equivalent Rb(2), and two equivalent Np(1) atoms to form a mixture of distorted face, corner, and edge-sharing ORb4Np2 octahedra. The corner-sharing octahedral tilt angles range from 0-61°. In the second O site, O(2) is bonded to four equivalent Rb(2) and two equivalent Np(1) atoms to form a mixture of distorted face, corner, and edge-sharing ORb4Np2 octahedra. The corner-sharing octahedral tilt angles range from 0-61°. is represented by the CIF file [CIF]
data_Rb2Np2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.355
_cell_length_b   4.355
_cell_length_c   8.939
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   169.499
_cell_formula_units_Z   1
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
  Rb  Rb0  1  0.000  0.000  0.000  1.0
  Rb  Rb1  1  0.000  0.000  0.500  1.0
  Np  Np2  1  0.500  0.500  0.259  1.0
  Np  Np3  1  0.500  0.500  0.741  1.0
  O  O4  1  0.500  0.000  0.236  1.0
  O  O5  1  0.500  0.000  0.764  1.0
  O  O6  1  0.500  0.500  0.500  1.0
  O  O7  1  0.000  0.500  0.236  1.0
  O  O8  1  0.000  0.500  0.764  1.0
[/CIF]
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The structure described by Rb2Np2O5 crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. In the second Rb site, Rb(2) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form RbO12 cuboctahedra that share corners with four equivalent Rb(2)O12 cuboctahedra, faces with four equivalent Rb(2)O12 cuboctahedra, and faces with eight equivalent Np(1)O5 square pyramids. Np(1) is bonded to one O(2) and four equivalent O(1) atoms to form NpO5 square pyramids that share corners with five equivalent Np(1)O5 square pyramids and faces with four equivalent Rb(2)O12 cuboctahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Rb(1), two equivalent Rb(2), and two equivalent Np(1) atoms to form a mixture of distorted face, corner, and edge-sharing ORb4Np2 octahedra. The corner-sharing octahedral tilt angles range from 0-61°. In the second O site, O(2) is bonded to four equivalent Rb(2) and two equivalent Np(1) atoms to form a mixture of distorted face, corner, and edge-sharing ORb4Np2 octahedra. The corner-sharing octahedral tilt angles range from 0-61°. is represented by the CIF file [CIF]
data_Rb2Np2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.355
_cell_length_b   4.355
_cell_length_c   8.939
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   169.499
_cell_formula_units_Z   1
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
  Rb  Rb0  1  0.000  0.000  0.000  1.0
  Rb  Rb1  1  0.000  0.000  0.500  1.0
  Np  Np2  1  0.500  0.500  0.259  1.0
  Np  Np3  1  0.500  0.500  0.741  1.0
  O  O4  1  0.500  0.000  0.236  1.0
  O  O5  1  0.500  0.000  0.764  1.0
  O  O6  1  0.500  0.500  0.500  1.0
  O  O7  1  0.000  0.500  0.236  1.0
  O  O8  1  0.000  0.500  0.764  1.0
[/CIF]
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