The compound described by Np2Mo3Si4 is delta Molybdenum Boride-derived structured and crystallizes in the monoclinic P2_1/c space group. Np(1) is bonded in a 7-coordinate geometry to three equivalent Si(2) and four equivalent Si(1) atoms. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded in a 6-coordinate geometry to three equivalent Si(1) and three equivalent Si(2) atoms. In the second Mo site, Mo(2) is bonded to two equivalent Si(1) and four equivalent Si(2) atoms to form distorted corner-sharing MoSi6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to four equivalent Np(1), one Mo(2), three equivalent Mo(1), and one Si(1) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to three equivalent Np(1), two equivalent Mo(2), three equivalent Mo(1), and one Si(2) atom. is represented by the CIF file [CIF]
data_Np2Si4Mo3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.788
_cell_length_b   6.900
_cell_length_c   6.912
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   109.496
_symmetry_Int_Tables_number   1
_cell_volume   305.198
_cell_formula_units_Z   2
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  0.560  0.686  0.164  1.0
  Np  Np1  1  0.940  0.314  0.664  1.0
  Np  Np2  1  0.060  0.686  0.336  1.0
  Np  Np3  1  0.440  0.314  0.836  1.0
  Si  Si4  1  0.625  0.409  0.456  1.0
  Si  Si5  1  0.125  0.409  0.044  1.0
  Si  Si6  1  0.869  0.001  0.368  1.0
  Si  Si7  1  0.369  0.001  0.132  1.0
  Si  Si8  1  0.875  0.591  0.956  1.0
  Si  Si9  1  0.131  0.999  0.632  1.0
  Si  Si10  1  0.375  0.591  0.544  1.0
  Si  Si11  1  0.631  0.999  0.868  1.0
  Mo  Mo12  1  0.247  0.251  0.333  1.0
  Mo  Mo13  1  0.753  0.749  0.667  1.0
  Mo  Mo14  1  0.747  0.251  0.167  1.0
  Mo  Mo15  1  0.500  0.000  0.500  1.0
  Mo  Mo16  1  0.000  0.000  0.000  1.0
  Mo  Mo17  1  0.253  0.749  0.833  1.0
[/CIF]
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The compound described by Np2Mo3Si4 is delta Molybdenum Boride-derived structured and crystallizes in the monoclinic P2_1/c space group. Np(1) is bonded in a 7-coordinate geometry to three equivalent Si(2) and four equivalent Si(1) atoms. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded in a 6-coordinate geometry to three equivalent Si(1) and three equivalent Si(2) atoms. In the second Mo site, Mo(2) is bonded to two equivalent Si(1) and four equivalent Si(2) atoms to form distorted corner-sharing MoSi6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to four equivalent Np(1), one Mo(2), three equivalent Mo(1), and one Si(1) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to three equivalent Np(1), two equivalent Mo(2), three equivalent Mo(1), and one Si(2) atom. is represented by the CIF file [CIF]
data_Np2Si4Mo3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.788
_cell_length_b   6.900
_cell_length_c   6.912
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   109.496
_symmetry_Int_Tables_number   1
_cell_volume   305.198
_cell_formula_units_Z   2
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  0.560  0.686  0.164  1.0
  Np  Np1  1  0.940  0.314  0.664  1.0
  Np  Np2  1  0.060  0.686  0.336  1.0
  Np  Np3  1  0.440  0.314  0.836  1.0
  Si  Si4  1  0.625  0.409  0.456  1.0
  Si  Si5  1  0.125  0.409  0.044  1.0
  Si  Si6  1  0.869  0.001  0.368  1.0
  Si  Si7  1  0.369  0.001  0.132  1.0
  Si  Si8  1  0.875  0.591  0.956  1.0
  Si  Si9  1  0.131  0.999  0.632  1.0
  Si  Si10  1  0.375  0.591  0.544  1.0
  Si  Si11  1  0.631  0.999  0.868  1.0
  Mo  Mo12  1  0.247  0.251  0.333  1.0
  Mo  Mo13  1  0.753  0.749  0.667  1.0
  Mo  Mo14  1  0.747  0.251  0.167  1.0
  Mo  Mo15  1  0.500  0.000  0.500  1.0
  Mo  Mo16  1  0.000  0.000  0.000  1.0
  Mo  Mo17  1  0.253  0.749  0.833  1.0
[/CIF]
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