The crystal structure described by Np3Hg is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Np sites. In the first Np site, Np(1) is bonded to four equivalent Np(1), four equivalent Np(2), and four equivalent Hg(1) atoms to form distorted NpNp8Hg4 cuboctahedra that share corners with twelve equivalent Np(1)Np8Hg4 cuboctahedra, edges with eight equivalent Np(1)Np8Hg4 cuboctahedra, edges with eight equivalent Hg(1)Np12 cuboctahedra, faces with four equivalent Hg(1)Np12 cuboctahedra, and faces with ten equivalent Np(1)Np8Hg4 cuboctahedra. In the second Np site, Np(2) is bonded in a distorted square co-planar geometry to eight equivalent Np(1) and four equivalent Hg(1) atoms. Hg(1) is bonded to four equivalent Np(2) and eight equivalent Np(1) atoms to form HgNp12 cuboctahedra that share corners with four equivalent Hg(1)Np12 cuboctahedra, edges with eight equivalent Hg(1)Np12 cuboctahedra, edges with sixteen equivalent Np(1)Np8Hg4 cuboctahedra, faces with four equivalent Hg(1)Np12 cuboctahedra, and faces with eight equivalent Np(1)Np8Hg4 cuboctahedra. is represented by the CIF file [CIF]
data_Np3Hg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.705
_cell_length_b   5.705
_cell_length_c   5.705
_cell_angle_alpha   133.136
_cell_angle_beta   133.136
_cell_angle_gamma   68.440
_symmetry_Int_Tables_number   1
_cell_volume   97.112
_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
  Np  Np0  1  0.750  0.250  0.500  1.0
  Np  Np1  1  0.250  0.750  0.500  1.0
  Np  Np2  1  0.500  0.500  0.000  1.0
  Hg  Hg3  1  0.000  0.000  0.000  1.0
[/CIF]
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The crystal structure described by Np3Hg is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Np sites. In the first Np site, Np(1) is bonded to four equivalent Np(1), four equivalent Np(2), and four equivalent Hg(1) atoms to form distorted NpNp8Hg4 cuboctahedra that share corners with twelve equivalent Np(1)Np8Hg4 cuboctahedra, edges with eight equivalent Np(1)Np8Hg4 cuboctahedra, edges with eight equivalent Hg(1)Np12 cuboctahedra, faces with four equivalent Hg(1)Np12 cuboctahedra, and faces with ten equivalent Np(1)Np8Hg4 cuboctahedra. In the second Np site, Np(2) is bonded in a distorted square co-planar geometry to eight equivalent Np(1) and four equivalent Hg(1) atoms. Hg(1) is bonded to four equivalent Np(2) and eight equivalent Np(1) atoms to form HgNp12 cuboctahedra that share corners with four equivalent Hg(1)Np12 cuboctahedra, edges with eight equivalent Hg(1)Np12 cuboctahedra, edges with sixteen equivalent Np(1)Np8Hg4 cuboctahedra, faces with four equivalent Hg(1)Np12 cuboctahedra, and faces with eight equivalent Np(1)Np8Hg4 cuboctahedra. is represented by the CIF file [CIF]
data_Np3Hg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.705
_cell_length_b   5.705
_cell_length_c   5.705
_cell_angle_alpha   133.136
_cell_angle_beta   133.136
_cell_angle_gamma   68.440
_symmetry_Int_Tables_number   1
_cell_volume   97.112
_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
  Np  Np0  1  0.750  0.250  0.500  1.0
  Np  Np1  1  0.250  0.750  0.500  1.0
  Np  Np2  1  0.500  0.500  0.000  1.0
  Hg  Hg3  1  0.000  0.000  0.000  1.0
[/CIF]
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