The crystal structure described by Mo5Fe3N8 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. There are three inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to one N(2), one N(3), two equivalent N(1), and two equivalent N(4) atoms to form distorted MoN6 pentagonal pyramids that share corners with two equivalent Fe(1)N6 octahedra, corners with four equivalent Mo(3)N6 octahedra, corners with six equivalent Fe(2)N6 octahedra, edges with two equivalent Mo(1)N6 pentagonal pyramids, edges with four equivalent Mo(2)N6 pentagonal pyramids,  a faceface with one Fe(1)N6 octahedra, and  a faceface with one Fe(2)N6 octahedra. The corner-sharing octahedral tilt angles range from 45-46°. In the second Mo site, Mo(2) is bonded to one N(1), one N(4), two equivalent N(2), and two equivalent N(3) atoms to form distorted MoN6 pentagonal pyramids that share corners with two equivalent Mo(3)N6 octahedra, corners with four equivalent Fe(1)N6 octahedra, corners with six equivalent Fe(2)N6 octahedra, edges with two equivalent Mo(2)N6 pentagonal pyramids, edges with four equivalent Mo(1)N6 pentagonal pyramids,  a faceface with one Mo(3)N6 octahedra, and  a faceface with one Fe(2)N6 octahedra. The corner-sharing octahedral tilt angles range from 44-47°. In the third Mo site, Mo(3) is bonded to two equivalent N(1) and four equivalent N(2) atoms to form distorted MoN6 octahedra that share corners with four equivalent Mo(2)N6 pentagonal pyramids, corners with eight equivalent Mo(1)N6 pentagonal pyramids, edges with two equivalent Mo(3)N6 octahedra, edges with four equivalent Fe(1)N6 octahedra, and faces with two equivalent Mo(2)N6 pentagonal pyramids. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent N(2) and four equivalent N(1) atoms to form FeN6 octahedra that share corners with four equivalent Mo(1)N6 pentagonal pyramids, corners with eight equivalent Mo(2)N6 pentagonal pyramids, edges with two equivalent Fe(1)N6 octahedra, edges with four equivalent Mo(3)N6 octahedra, and faces with two equivalent Mo(1)N6 pentagonal pyramids. In the second Fe site, Fe(2) is bonded to three equivalent N(3) and three equivalent N(4) atoms to form FeN6 octahedra that share corners with six equivalent Mo(1)N6 pentagonal pyramids, corners with six equivalent Mo(2)N6 pentagonal pyramids, edges with six equivalent Fe(2)N6 octahedra,  a faceface with one Mo(1)N6 pentagonal pyramid, and  a faceface with one Mo(2)N6 pentagonal pyramid. There are four inequivalent N sites. In the first N site, N(1) is bonded to one Mo(2), one Mo(3), two equivalent Mo(1), and two equivalent Fe(1) atoms to form distorted NFe2Mo4 pentagonal pyramids that share corners with two equivalent N(4)Fe3Mo3 pentagonal pyramids, corners with three equivalent N(1)Fe2Mo4 pentagonal pyramids, corners with four equivalent N(3)Fe3Mo3 pentagonal pyramids, edges with three equivalent N(1)Fe2Mo4 pentagonal pyramids, edges with six equivalent N(2)FeMo5 pentagonal pyramids, and  a faceface with one N(4)Fe3Mo3 pentagonal pyramid. In the second N site, N(2) is bonded to one Mo(1), two equivalent Mo(2), two equivalent Mo(3), and one Fe(1) atom to form distorted NFeMo5 pentagonal pyramids that share corners with two equivalent N(3)Fe3Mo3 pentagonal pyramids, corners with three equivalent N(2)FeMo5 pentagonal pyramids, corners with four equivalent N(4)Fe3Mo3 pentagonal pyramids, edges with three equivalent N(2)FeMo5 pentagonal pyramids, edges with six equivalent N(1)Fe2Mo4 pentagonal pyramids, and  a faceface with one N(3)Fe3Mo3 pentagonal pyramid. In the third N site, N(3) is bonded to one Mo(1), two equivalent Mo(2), and three equivalent Fe(2) atoms to form distorted NFe3Mo3 pentagonal pyramids that share corners with two equivalent N(2)FeMo5 pentagonal pyramids, corners with three equivalent N(4)Fe3Mo3 pentagonal pyramids, corners with four equivalent N(1)Fe2Mo4 pentagonal pyramids, edges with four equivalent N(3)Fe3Mo3 pentagonal pyramids, edges with five equivalent N(4)Fe3Mo3 pentagonal pyramids, and  a faceface with one N(2)FeMo5 pentagonal pyramid. In the fourth N site, N(4) is bonded to one Mo(2), two equivalent Mo(1), and three equivalent Fe(2) atoms to form distorted NFe3Mo3 pentagonal pyramids that share corners with two equivalent N(1)Fe2Mo4 pentagonal pyramids, corners with three equivalent N(3)Fe3Mo3 pentagonal pyramids, corners with four equivalent N(2)FeMo5 pentagonal pyramids, edges with four equivalent N(4)Fe3Mo3 pentagonal pyramids, edges with five equivalent N(3)Fe3Mo3 pentagonal pyramids, and  a faceface with one N(1)Fe2Mo4 pentagonal pyramid. is represented by the Crystallographic Information File (CIF) [CIF]
data_Fe3Mo5N8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.282
_cell_length_b   11.282
_cell_length_c   4.969
_cell_angle_alpha   77.852
_cell_angle_beta   77.852
_cell_angle_gamma   14.581
_symmetry_Int_Tables_number   1
_cell_volume   155.610
_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
  Fe  Fe0  1  0.000  0.000  0.000  1.0
  Fe  Fe1  1  0.249  0.249  0.749  1.0
  Fe  Fe2  1  0.751  0.751  0.251  1.0
  Mo  Mo3  1  0.128  0.128  0.871  1.0
  Mo  Mo4  1  0.629  0.629  0.373  1.0
  Mo  Mo5  1  0.872  0.872  0.129  1.0
  Mo  Mo6  1  0.371  0.371  0.627  1.0
  Mo  Mo7  1  0.500  0.500  0.500  1.0
  N  N8  1  0.567  0.567  0.763  1.0
  N  N9  1  0.067  0.067  0.268  1.0
  N  N10  1  0.810  0.810  0.854  1.0
  N  N11  1  0.310  0.310  0.353  1.0
  N  N12  1  0.933  0.933  0.732  1.0
  N  N13  1  0.433  0.433  0.237  1.0
  N  N14  1  0.690  0.690  0.647  1.0
  N  N15  1  0.190  0.190  0.146  1.0
[/CIF]
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The crystal structure described by Mo5Fe3N8 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. There are three inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to one N(2), one N(3), two equivalent N(1), and two equivalent N(4) atoms to form distorted MoN6 pentagonal pyramids that share corners with two equivalent Fe(1)N6 octahedra, corners with four equivalent Mo(3)N6 octahedra, corners with six equivalent Fe(2)N6 octahedra, edges with two equivalent Mo(1)N6 pentagonal pyramids, edges with four equivalent Mo(2)N6 pentagonal pyramids,  a faceface with one Fe(1)N6 octahedra, and  a faceface with one Fe(2)N6 octahedra. The corner-sharing octahedral tilt angles range from 45-46°. In the second Mo site, Mo(2) is bonded to one N(1), one N(4), two equivalent N(2), and two equivalent N(3) atoms to form distorted MoN6 pentagonal pyramids that share corners with two equivalent Mo(3)N6 octahedra, corners with four equivalent Fe(1)N6 octahedra, corners with six equivalent Fe(2)N6 octahedra, edges with two equivalent Mo(2)N6 pentagonal pyramids, edges with four equivalent Mo(1)N6 pentagonal pyramids,  a faceface with one Mo(3)N6 octahedra, and  a faceface with one Fe(2)N6 octahedra. The corner-sharing octahedral tilt angles range from 44-47°. In the third Mo site, Mo(3) is bonded to two equivalent N(1) and four equivalent N(2) atoms to form distorted MoN6 octahedra that share corners with four equivalent Mo(2)N6 pentagonal pyramids, corners with eight equivalent Mo(1)N6 pentagonal pyramids, edges with two equivalent Mo(3)N6 octahedra, edges with four equivalent Fe(1)N6 octahedra, and faces with two equivalent Mo(2)N6 pentagonal pyramids. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent N(2) and four equivalent N(1) atoms to form FeN6 octahedra that share corners with four equivalent Mo(1)N6 pentagonal pyramids, corners with eight equivalent Mo(2)N6 pentagonal pyramids, edges with two equivalent Fe(1)N6 octahedra, edges with four equivalent Mo(3)N6 octahedra, and faces with two equivalent Mo(1)N6 pentagonal pyramids. In the second Fe site, Fe(2) is bonded to three equivalent N(3) and three equivalent N(4) atoms to form FeN6 octahedra that share corners with six equivalent Mo(1)N6 pentagonal pyramids, corners with six equivalent Mo(2)N6 pentagonal pyramids, edges with six equivalent Fe(2)N6 octahedra,  a faceface with one Mo(1)N6 pentagonal pyramid, and  a faceface with one Mo(2)N6 pentagonal pyramid. There are four inequivalent N sites. In the first N site, N(1) is bonded to one Mo(2), one Mo(3), two equivalent Mo(1), and two equivalent Fe(1) atoms to form distorted NFe2Mo4 pentagonal pyramids that share corners with two equivalent N(4)Fe3Mo3 pentagonal pyramids, corners with three equivalent N(1)Fe2Mo4 pentagonal pyramids, corners with four equivalent N(3)Fe3Mo3 pentagonal pyramids, edges with three equivalent N(1)Fe2Mo4 pentagonal pyramids, edges with six equivalent N(2)FeMo5 pentagonal pyramids, and  a faceface with one N(4)Fe3Mo3 pentagonal pyramid. In the second N site, N(2) is bonded to one Mo(1), two equivalent Mo(2), two equivalent Mo(3), and one Fe(1) atom to form distorted NFeMo5 pentagonal pyramids that share corners with two equivalent N(3)Fe3Mo3 pentagonal pyramids, corners with three equivalent N(2)FeMo5 pentagonal pyramids, corners with four equivalent N(4)Fe3Mo3 pentagonal pyramids, edges with three equivalent N(2)FeMo5 pentagonal pyramids, edges with six equivalent N(1)Fe2Mo4 pentagonal pyramids, and  a faceface with one N(3)Fe3Mo3 pentagonal pyramid. In the third N site, N(3) is bonded to one Mo(1), two equivalent Mo(2), and three equivalent Fe(2) atoms to form distorted NFe3Mo3 pentagonal pyramids that share corners with two equivalent N(2)FeMo5 pentagonal pyramids, corners with three equivalent N(4)Fe3Mo3 pentagonal pyramids, corners with four equivalent N(1)Fe2Mo4 pentagonal pyramids, edges with four equivalent N(3)Fe3Mo3 pentagonal pyramids, edges with five equivalent N(4)Fe3Mo3 pentagonal pyramids, and  a faceface with one N(2)FeMo5 pentagonal pyramid. In the fourth N site, N(4) is bonded to one Mo(2), two equivalent Mo(1), and three equivalent Fe(2) atoms to form distorted NFe3Mo3 pentagonal pyramids that share corners with two equivalent N(1)Fe2Mo4 pentagonal pyramids, corners with three equivalent N(3)Fe3Mo3 pentagonal pyramids, corners with four equivalent N(2)FeMo5 pentagonal pyramids, edges with four equivalent N(4)Fe3Mo3 pentagonal pyramids, edges with five equivalent N(3)Fe3Mo3 pentagonal pyramids, and  a faceface with one N(1)Fe2Mo4 pentagonal pyramid. is represented by the Crystallographic Information File (CIF) [CIF]
data_Fe3Mo5N8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.282
_cell_length_b   11.282
_cell_length_c   4.969
_cell_angle_alpha   77.852
_cell_angle_beta   77.852
_cell_angle_gamma   14.581
_symmetry_Int_Tables_number   1
_cell_volume   155.610
_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
  Fe  Fe0  1  0.000  0.000  0.000  1.0
  Fe  Fe1  1  0.249  0.249  0.749  1.0
  Fe  Fe2  1  0.751  0.751  0.251  1.0
  Mo  Mo3  1  0.128  0.128  0.871  1.0
  Mo  Mo4  1  0.629  0.629  0.373  1.0
  Mo  Mo5  1  0.872  0.872  0.129  1.0
  Mo  Mo6  1  0.371  0.371  0.627  1.0
  Mo  Mo7  1  0.500  0.500  0.500  1.0
  N  N8  1  0.567  0.567  0.763  1.0
  N  N9  1  0.067  0.067  0.268  1.0
  N  N10  1  0.810  0.810  0.854  1.0
  N  N11  1  0.310  0.310  0.353  1.0
  N  N12  1  0.933  0.933  0.732  1.0
  N  N13  1  0.433  0.433  0.237  1.0
  N  N14  1  0.690  0.690  0.647  1.0
  N  N15  1  0.190  0.190  0.146  1.0
[/CIF]
.