The compound described by MgNp3 is alpha La-derived structured and crystallizes in the tetragonal I4/mmm space group. Mg(1) is bonded to four equivalent Np(1) and eight equivalent Np(2) atoms to form MgNp12 cuboctahedra that share corners with four equivalent Mg(1)Np12 cuboctahedra, corners with eight equivalent Np(1)Mg4Np8 cuboctahedra, edges with eight equivalent Mg(1)Np12 cuboctahedra, edges with sixteen equivalent Np(2)Mg4Np8 cuboctahedra, faces with four equivalent Mg(1)Np12 cuboctahedra, faces with six equivalent Np(1)Mg4Np8 cuboctahedra, and faces with eight equivalent Np(2)Mg4Np8 cuboctahedra. There are two inequivalent Np sites. In the first Np site, Np(1) is bonded to four equivalent Mg(1) and eight equivalent Np(2) atoms to form NpMg4Np8 cuboctahedra that share corners with four equivalent Np(1)Mg4Np8 cuboctahedra, corners with eight equivalent Mg(1)Np12 cuboctahedra, edges with eight equivalent Np(1)Mg4Np8 cuboctahedra, edges with sixteen equivalent Np(2)Mg4Np8 cuboctahedra, faces with four equivalent Np(1)Mg4Np8 cuboctahedra, faces with six equivalent Mg(1)Np12 cuboctahedra, and faces with eight equivalent Np(2)Mg4Np8 cuboctahedra. In the second Np site, Np(2) is bonded to four equivalent Mg(1), four equivalent Np(1), and four equivalent Np(2) atoms to form NpMg4Np8 cuboctahedra that share corners with twelve equivalent Np(2)Mg4Np8 cuboctahedra, edges with eight equivalent Mg(1)Np12 cuboctahedra, edges with eight equivalent Np(1)Mg4Np8 cuboctahedra, edges with eight equivalent Np(2)Mg4Np8 cuboctahedra, faces with four equivalent Mg(1)Np12 cuboctahedra, faces with four equivalent Np(1)Mg4Np8 cuboctahedra, and faces with ten equivalent Np(2)Mg4Np8 cuboctahedra. is represented by the CIF file [CIF]
data_MgNp3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.287
_cell_length_b   5.287
_cell_length_c   5.287
_cell_angle_alpha   131.016
_cell_angle_beta   131.016
_cell_angle_gamma   71.788
_symmetry_Int_Tables_number   1
_cell_volume   82.313
_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
  Mg  Mg0  1  0.000  0.000  0.000  1.0
  Np  Np1  1  0.500  0.500  0.000  1.0
  Np  Np2  1  0.750  0.250  0.500  1.0
  Np  Np3  1  0.250  0.750  0.500  1.0
[/CIF]
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The compound described by MgNp3 is alpha La-derived structured and crystallizes in the tetragonal I4/mmm space group. Mg(1) is bonded to four equivalent Np(1) and eight equivalent Np(2) atoms to form MgNp12 cuboctahedra that share corners with four equivalent Mg(1)Np12 cuboctahedra, corners with eight equivalent Np(1)Mg4Np8 cuboctahedra, edges with eight equivalent Mg(1)Np12 cuboctahedra, edges with sixteen equivalent Np(2)Mg4Np8 cuboctahedra, faces with four equivalent Mg(1)Np12 cuboctahedra, faces with six equivalent Np(1)Mg4Np8 cuboctahedra, and faces with eight equivalent Np(2)Mg4Np8 cuboctahedra. There are two inequivalent Np sites. In the first Np site, Np(1) is bonded to four equivalent Mg(1) and eight equivalent Np(2) atoms to form NpMg4Np8 cuboctahedra that share corners with four equivalent Np(1)Mg4Np8 cuboctahedra, corners with eight equivalent Mg(1)Np12 cuboctahedra, edges with eight equivalent Np(1)Mg4Np8 cuboctahedra, edges with sixteen equivalent Np(2)Mg4Np8 cuboctahedra, faces with four equivalent Np(1)Mg4Np8 cuboctahedra, faces with six equivalent Mg(1)Np12 cuboctahedra, and faces with eight equivalent Np(2)Mg4Np8 cuboctahedra. In the second Np site, Np(2) is bonded to four equivalent Mg(1), four equivalent Np(1), and four equivalent Np(2) atoms to form NpMg4Np8 cuboctahedra that share corners with twelve equivalent Np(2)Mg4Np8 cuboctahedra, edges with eight equivalent Mg(1)Np12 cuboctahedra, edges with eight equivalent Np(1)Mg4Np8 cuboctahedra, edges with eight equivalent Np(2)Mg4Np8 cuboctahedra, faces with four equivalent Mg(1)Np12 cuboctahedra, faces with four equivalent Np(1)Mg4Np8 cuboctahedra, and faces with ten equivalent Np(2)Mg4Np8 cuboctahedra. is represented by the CIF file [CIF]
data_MgNp3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.287
_cell_length_b   5.287
_cell_length_c   5.287
_cell_angle_alpha   131.016
_cell_angle_beta   131.016
_cell_angle_gamma   71.788
_symmetry_Int_Tables_number   1
_cell_volume   82.313
_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
  Mg  Mg0  1  0.000  0.000  0.000  1.0
  Np  Np1  1  0.500  0.500  0.000  1.0
  Np  Np2  1  0.750  0.250  0.500  1.0
  Np  Np3  1  0.250  0.750  0.500  1.0
[/CIF]
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