The compound 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 trigonal bipyramids. There are three inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 6-coordinate geometry to one O(1), 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 trigonal bipyramids that share  a cornercorner with one Np(1)O6 octahedra and  an edgeedge with one Yb(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 10°. In the third Yb site, Yb(3) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(5), one O(6), and two equivalent O(1) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Np(1), one Yb(1), and two equivalent Yb(3) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Np(1), one Yb(1), and one Yb(3) atom. In the third O site, O(3) is bonded in a distorted 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 3-coordinate geometry to two equivalent Yb(2) and one O(5) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Yb(1), one Yb(2), one Yb(3), and one O(4) atom. In the sixth O site, O(6) is bonded to one Yb(2), one Yb(3), and two equivalent Yb(1) atoms to form edge-sharing OYb4 tetrahedra. is represented by the CIF file [CIF]
data_Yb6NpO12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.016
_cell_length_b   8.442
_cell_length_c   8.815
_cell_angle_alpha   136.057
_cell_angle_beta   114.002
_cell_angle_gamma   50.522
_symmetry_Int_Tables_number   1
_cell_volume   397.427
_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  0.100  0.841  0.282  1.0
  Yb  Yb1  1  0.900  0.159  0.718  1.0
  Yb  Yb2  1  0.688  0.950  0.156  1.0
  Yb  Yb3  1  0.312  0.050  0.844  1.0
  Yb  Yb4  1  0.976  0.495  0.690  1.0
  Yb  Yb5  1  0.024  0.505  0.310  1.0
  Np  Np6  1  0.000  0.000  0.000  1.0
  O  O7  1  0.955  0.797  0.676  1.0
  O  O8  1  0.045  0.203  0.324  1.0
  O  O9  1  0.174  0.648  0.927  1.0
  O  O10  1  0.826  0.352  0.073  1.0
  O  O11  1  0.850  0.946  0.047  1.0
  O  O12  1  0.150  0.054  0.953  1.0
  O  O13  1  0.568  0.719  0.840  1.0
  O  O14  1  0.432  0.281  0.160  1.0
  O  O15  1  0.750  0.559  0.787  1.0
  O  O16  1  0.250  0.441  0.213  1.0
  O  O17  1  0.895  0.868  0.355  1.0
  O  O18  1  0.105  0.132  0.645  1.0
[/CIF]
.
The compound 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 trigonal bipyramids. There are three inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 6-coordinate geometry to one O(1), 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 trigonal bipyramids that share  a cornercorner with one Np(1)O6 octahedra and  an edgeedge with one Yb(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 10°. In the third Yb site, Yb(3) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(5), one O(6), and two equivalent O(1) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Np(1), one Yb(1), and two equivalent Yb(3) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Np(1), one Yb(1), and one Yb(3) atom. In the third O site, O(3) is bonded in a distorted 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 3-coordinate geometry to two equivalent Yb(2) and one O(5) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Yb(1), one Yb(2), one Yb(3), and one O(4) atom. In the sixth O site, O(6) is bonded to one Yb(2), one Yb(3), and two equivalent Yb(1) atoms to form edge-sharing OYb4 tetrahedra. is represented by the CIF file [CIF]
data_Yb6NpO12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.016
_cell_length_b   8.442
_cell_length_c   8.815
_cell_angle_alpha   136.057
_cell_angle_beta   114.002
_cell_angle_gamma   50.522
_symmetry_Int_Tables_number   1
_cell_volume   397.427
_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  0.100  0.841  0.282  1.0
  Yb  Yb1  1  0.900  0.159  0.718  1.0
  Yb  Yb2  1  0.688  0.950  0.156  1.0
  Yb  Yb3  1  0.312  0.050  0.844  1.0
  Yb  Yb4  1  0.976  0.495  0.690  1.0
  Yb  Yb5  1  0.024  0.505  0.310  1.0
  Np  Np6  1  0.000  0.000  0.000  1.0
  O  O7  1  0.955  0.797  0.676  1.0
  O  O8  1  0.045  0.203  0.324  1.0
  O  O9  1  0.174  0.648  0.927  1.0
  O  O10  1  0.826  0.352  0.073  1.0
  O  O11  1  0.850  0.946  0.047  1.0
  O  O12  1  0.150  0.054  0.953  1.0
  O  O13  1  0.568  0.719  0.840  1.0
  O  O14  1  0.432  0.281  0.160  1.0
  O  O15  1  0.750  0.559  0.787  1.0
  O  O16  1  0.250  0.441  0.213  1.0
  O  O17  1  0.895  0.868  0.355  1.0
  O  O18  1  0.105  0.132  0.645  1.0
[/CIF]
.