The crystal structure described by NpYb6O12 crystallizes in the triclinic P-1 space group. Np(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form NpO6 octahedra that share corners with two equivalent Yb(2)O5 square pyramids. There are three inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(5), and two equivalent O(6) atoms. In the second Yb site, Yb(2) is bonded to one O(3), one O(5), one O(6), and two equivalent O(4) atoms to form distorted YbO5 square pyramids that share  a cornercorner with one Np(1)O6 octahedra and  an edgeedge with one Yb(2)O5 square pyramid. The corner-sharing octahedral tilt angles are 4°. In the third Yb site, Yb(3) is bonded in a distorted pentagonal planar geometry to one O(3), one O(4), one O(5), and two equivalent O(1) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Np(1) and two equivalent Yb(3) atoms. In the second O site, O(2) is bonded in a distorted water-like geometry to one Np(1) and one Yb(1) atom. In the third O site, O(3) is bonded in a see-saw-like geometry to one Np(1), one Yb(1), one Yb(2), and one Yb(3) atom. In the fourth O site, O(4) is bonded in a T-shaped geometry to one Yb(3) and two equivalent Yb(2) atoms. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Yb(1), one Yb(2), and one Yb(3) atom. In the sixth O site, O(6) is bonded in a T-shaped geometry to one Yb(2) and two equivalent Yb(1) atoms. is represented by the CIF file [CIF]
data_Yb6NpO12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.697
_cell_length_b   9.267
_cell_length_c   9.069
_cell_angle_alpha   140.011
_cell_angle_beta   113.460
_cell_angle_gamma   56.545
_symmetry_Int_Tables_number   1
_cell_volume   436.544
_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
  Yb  Yb0  1  0.067  0.828  0.239  1.0
  Yb  Yb1  1  0.933  0.172  0.761  1.0
  Yb  Yb2  1  0.672  0.902  0.111  1.0
  Yb  Yb3  1  0.328  0.098  0.889  1.0
  Yb  Yb4  1  0.858  0.577  0.655  1.0
  Yb  Yb5  1  0.142  0.423  0.345  1.0
  Np  Np6  1  0.000  0.000  0.000  1.0
  O  O7  1  0.969  0.756  0.660  1.0
  O  O8  1  0.031  0.244  0.340  1.0
  O  O9  1  0.168  0.736  0.969  1.0
  O  O10  1  0.832  0.264  0.031  1.0
  O  O11  1  0.844  0.939  0.041  1.0
  O  O12  1  0.156  0.061  0.959  1.0
  O  O13  1  0.594  0.805  0.775  1.0
  O  O14  1  0.406  0.195  0.225  1.0
  O  O15  1  0.853  0.500  0.837  1.0
  O  O16  1  0.147  0.500  0.163  1.0
  O  O17  1  0.841  0.973  0.402  1.0
  O  O18  1  0.159  0.027  0.598  1.0
[/CIF]
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The crystal structure described by NpYb6O12 crystallizes in the triclinic P-1 space group. Np(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form NpO6 octahedra that share corners with two equivalent Yb(2)O5 square pyramids. There are three inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(5), and two equivalent O(6) atoms. In the second Yb site, Yb(2) is bonded to one O(3), one O(5), one O(6), and two equivalent O(4) atoms to form distorted YbO5 square pyramids that share  a cornercorner with one Np(1)O6 octahedra and  an edgeedge with one Yb(2)O5 square pyramid. The corner-sharing octahedral tilt angles are 4°. In the third Yb site, Yb(3) is bonded in a distorted pentagonal planar geometry to one O(3), one O(4), one O(5), and two equivalent O(1) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Np(1) and two equivalent Yb(3) atoms. In the second O site, O(2) is bonded in a distorted water-like geometry to one Np(1) and one Yb(1) atom. In the third O site, O(3) is bonded in a see-saw-like geometry to one Np(1), one Yb(1), one Yb(2), and one Yb(3) atom. In the fourth O site, O(4) is bonded in a T-shaped geometry to one Yb(3) and two equivalent Yb(2) atoms. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Yb(1), one Yb(2), and one Yb(3) atom. In the sixth O site, O(6) is bonded in a T-shaped geometry to one Yb(2) and two equivalent Yb(1) atoms. is represented by the CIF file [CIF]
data_Yb6NpO12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.697
_cell_length_b   9.267
_cell_length_c   9.069
_cell_angle_alpha   140.011
_cell_angle_beta   113.460
_cell_angle_gamma   56.545
_symmetry_Int_Tables_number   1
_cell_volume   436.544
_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
  Yb  Yb0  1  0.067  0.828  0.239  1.0
  Yb  Yb1  1  0.933  0.172  0.761  1.0
  Yb  Yb2  1  0.672  0.902  0.111  1.0
  Yb  Yb3  1  0.328  0.098  0.889  1.0
  Yb  Yb4  1  0.858  0.577  0.655  1.0
  Yb  Yb5  1  0.142  0.423  0.345  1.0
  Np  Np6  1  0.000  0.000  0.000  1.0
  O  O7  1  0.969  0.756  0.660  1.0
  O  O8  1  0.031  0.244  0.340  1.0
  O  O9  1  0.168  0.736  0.969  1.0
  O  O10  1  0.832  0.264  0.031  1.0
  O  O11  1  0.844  0.939  0.041  1.0
  O  O12  1  0.156  0.061  0.959  1.0
  O  O13  1  0.594  0.805  0.775  1.0
  O  O14  1  0.406  0.195  0.225  1.0
  O  O15  1  0.853  0.500  0.837  1.0
  O  O16  1  0.147  0.500  0.163  1.0
  O  O17  1  0.841  0.973  0.402  1.0
  O  O18  1  0.159  0.027  0.598  1.0
[/CIF]
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