The crystal structure described by FeSi4P4 crystallizes in the triclinic P1 space group. Fe(1) is bonded to one Si(1), one Si(3), one Si(4), one P(1), one P(2), and one P(4) atom to form FeSi3P3 octahedra that share corners with two equivalent Si(1)FeP3 tetrahedra, corners with two equivalent P(2)FeSi3 tetrahedra, corners with two equivalent P(4)FeSi3 tetrahedra, corners with three equivalent Si(2)P4 tetrahedra, corners with three equivalent P(3)Si4 tetrahedra, corners with two equivalent Si(4)FeP3 trigonal pyramids, and corners with two equivalent P(1)FeSi3 trigonal pyramids. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one Fe(1), one P(1), one P(2), and one P(3) atom to form distorted SiFeP3 tetrahedra that share corners with two equivalent Fe(1)Si3P3 octahedra,  a cornercorner with one P(2)FeSi3 tetrahedra,  a cornercorner with one P(4)FeSi3 tetrahedra, corners with three equivalent Si(2)P4 tetrahedra,  a cornercorner with one P(1)FeSi3 trigonal pyramid, and corners with three equivalent Si(4)FeP3 trigonal pyramids. The corner-sharing octahedral tilt angles range from 49-68°. In the second Si site, Si(2) is bonded to one P(1), one P(2), one P(3), and one P(4) atom to form SiP4 tetrahedra that share corners with three equivalent Fe(1)Si3P3 octahedra, corners with three equivalent Si(1)FeP3 tetrahedra, and corners with three equivalent Si(4)FeP3 trigonal pyramids. The corner-sharing octahedral tilt angles range from 53-75°. In the third Si site, Si(3) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1), one P(2), one P(3), and one P(4) atom. In the fourth Si site, Si(4) is bonded to one Fe(1), one P(1), one P(3), and one P(4) atom to form distorted SiFeP3 trigonal pyramids that share corners with two equivalent Fe(1)Si3P3 octahedra,  a cornercorner with one P(2)FeSi3 tetrahedra,  a cornercorner with one P(4)FeSi3 tetrahedra, corners with three equivalent Si(1)FeP3 tetrahedra, corners with three equivalent Si(2)P4 tetrahedra, and  a cornercorner with one P(1)FeSi3 trigonal pyramid. The corner-sharing octahedral tilt angles range from 59-70°. There are four inequivalent P sites. In the first P site, P(1) is bonded to one Fe(1), one Si(1), one Si(2), and one Si(4) atom to form PFeSi3 trigonal pyramids that share corners with two equivalent Fe(1)Si3P3 octahedra,  a cornercorner with one Si(1)FeP3 tetrahedra, corners with three equivalent P(2)FeSi3 tetrahedra, corners with three equivalent P(4)FeSi3 tetrahedra, corners with three equivalent P(3)Si4 tetrahedra, and  a cornercorner with one Si(4)FeP3 trigonal pyramid. The corner-sharing octahedral tilt angles range from 60-68°. In the second P site, P(2) is bonded to one Fe(1), one Si(1), one Si(2), and one Si(3) atom to form PFeSi3 tetrahedra that share corners with two equivalent Fe(1)Si3P3 octahedra,  a cornercorner with one Si(1)FeP3 tetrahedra, corners with three equivalent P(4)FeSi3 tetrahedra, corners with three equivalent P(3)Si4 tetrahedra,  a cornercorner with one Si(4)FeP3 trigonal pyramid, and corners with three equivalent P(1)FeSi3 trigonal pyramids. The corner-sharing octahedral tilt angles range from 50-62°. In the third P site, P(3) is bonded to one Si(1), one Si(2), one Si(3), and one Si(4) atom to form PSi4 tetrahedra that share corners with three equivalent Fe(1)Si3P3 octahedra, corners with three equivalent P(2)FeSi3 tetrahedra, corners with three equivalent P(4)FeSi3 tetrahedra, and corners with three equivalent P(1)FeSi3 trigonal pyramids. The corner-sharing octahedral tilt angles range from 49-73°. In the fourth P site, P(4) is bonded to one Fe(1), one Si(2), one Si(3), and one Si(4) atom to form PFeSi3 tetrahedra that share corners with two equivalent Fe(1)Si3P3 octahedra,  a cornercorner with one Si(1)FeP3 tetrahedra, corners with three equivalent P(2)FeSi3 tetrahedra, corners with three equivalent P(3)Si4 tetrahedra,  a cornercorner with one Si(4)FeP3 trigonal pyramid, and corners with three equivalent P(1)FeSi3 trigonal pyramids. The corner-sharing octahedral tilt angles range from 45-67°. is represented by the CIF card [CIF]
data_Fe(SiP)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.868
_cell_length_b   5.538
_cell_length_c   6.055
_cell_angle_alpha   85.368
_cell_angle_beta   68.376
_cell_angle_gamma   70.410
_symmetry_Int_Tables_number   1
_cell_volume   142.792
_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  1.000  1.000  0.000  1.0
  Si  Si1  1  0.680  0.777  0.217  1.0
  Si  Si2  1  0.238  0.338  0.431  1.0
  Si  Si3  1  0.346  0.599  0.885  1.0
  Si  Si4  1  0.847  0.971  0.697  1.0
  P  P5  1  0.156  0.011  0.309  1.0
  P  P6  1  0.633  0.400  0.118  1.0
  P  P7  1  0.764  0.642  0.565  1.0
  P  P8  1  0.329  0.219  0.768  1.0
[/CIF]
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The crystal structure described by FeSi4P4 crystallizes in the triclinic P1 space group. Fe(1) is bonded to one Si(1), one Si(3), one Si(4), one P(1), one P(2), and one P(4) atom to form FeSi3P3 octahedra that share corners with two equivalent Si(1)FeP3 tetrahedra, corners with two equivalent P(2)FeSi3 tetrahedra, corners with two equivalent P(4)FeSi3 tetrahedra, corners with three equivalent Si(2)P4 tetrahedra, corners with three equivalent P(3)Si4 tetrahedra, corners with two equivalent Si(4)FeP3 trigonal pyramids, and corners with two equivalent P(1)FeSi3 trigonal pyramids. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one Fe(1), one P(1), one P(2), and one P(3) atom to form distorted SiFeP3 tetrahedra that share corners with two equivalent Fe(1)Si3P3 octahedra,  a cornercorner with one P(2)FeSi3 tetrahedra,  a cornercorner with one P(4)FeSi3 tetrahedra, corners with three equivalent Si(2)P4 tetrahedra,  a cornercorner with one P(1)FeSi3 trigonal pyramid, and corners with three equivalent Si(4)FeP3 trigonal pyramids. The corner-sharing octahedral tilt angles range from 49-68°. In the second Si site, Si(2) is bonded to one P(1), one P(2), one P(3), and one P(4) atom to form SiP4 tetrahedra that share corners with three equivalent Fe(1)Si3P3 octahedra, corners with three equivalent Si(1)FeP3 tetrahedra, and corners with three equivalent Si(4)FeP3 trigonal pyramids. The corner-sharing octahedral tilt angles range from 53-75°. In the third Si site, Si(3) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1), one P(2), one P(3), and one P(4) atom. In the fourth Si site, Si(4) is bonded to one Fe(1), one P(1), one P(3), and one P(4) atom to form distorted SiFeP3 trigonal pyramids that share corners with two equivalent Fe(1)Si3P3 octahedra,  a cornercorner with one P(2)FeSi3 tetrahedra,  a cornercorner with one P(4)FeSi3 tetrahedra, corners with three equivalent Si(1)FeP3 tetrahedra, corners with three equivalent Si(2)P4 tetrahedra, and  a cornercorner with one P(1)FeSi3 trigonal pyramid. The corner-sharing octahedral tilt angles range from 59-70°. There are four inequivalent P sites. In the first P site, P(1) is bonded to one Fe(1), one Si(1), one Si(2), and one Si(4) atom to form PFeSi3 trigonal pyramids that share corners with two equivalent Fe(1)Si3P3 octahedra,  a cornercorner with one Si(1)FeP3 tetrahedra, corners with three equivalent P(2)FeSi3 tetrahedra, corners with three equivalent P(4)FeSi3 tetrahedra, corners with three equivalent P(3)Si4 tetrahedra, and  a cornercorner with one Si(4)FeP3 trigonal pyramid. The corner-sharing octahedral tilt angles range from 60-68°. In the second P site, P(2) is bonded to one Fe(1), one Si(1), one Si(2), and one Si(3) atom to form PFeSi3 tetrahedra that share corners with two equivalent Fe(1)Si3P3 octahedra,  a cornercorner with one Si(1)FeP3 tetrahedra, corners with three equivalent P(4)FeSi3 tetrahedra, corners with three equivalent P(3)Si4 tetrahedra,  a cornercorner with one Si(4)FeP3 trigonal pyramid, and corners with three equivalent P(1)FeSi3 trigonal pyramids. The corner-sharing octahedral tilt angles range from 50-62°. In the third P site, P(3) is bonded to one Si(1), one Si(2), one Si(3), and one Si(4) atom to form PSi4 tetrahedra that share corners with three equivalent Fe(1)Si3P3 octahedra, corners with three equivalent P(2)FeSi3 tetrahedra, corners with three equivalent P(4)FeSi3 tetrahedra, and corners with three equivalent P(1)FeSi3 trigonal pyramids. The corner-sharing octahedral tilt angles range from 49-73°. In the fourth P site, P(4) is bonded to one Fe(1), one Si(2), one Si(3), and one Si(4) atom to form PFeSi3 tetrahedra that share corners with two equivalent Fe(1)Si3P3 octahedra,  a cornercorner with one Si(1)FeP3 tetrahedra, corners with three equivalent P(2)FeSi3 tetrahedra, corners with three equivalent P(3)Si4 tetrahedra,  a cornercorner with one Si(4)FeP3 trigonal pyramid, and corners with three equivalent P(1)FeSi3 trigonal pyramids. The corner-sharing octahedral tilt angles range from 45-67°. is represented by the CIF card [CIF]
data_Fe(SiP)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.868
_cell_length_b   5.538
_cell_length_c   6.055
_cell_angle_alpha   85.368
_cell_angle_beta   68.376
_cell_angle_gamma   70.410
_symmetry_Int_Tables_number   1
_cell_volume   142.792
_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  1.000  1.000  0.000  1.0
  Si  Si1  1  0.680  0.777  0.217  1.0
  Si  Si2  1  0.238  0.338  0.431  1.0
  Si  Si3  1  0.346  0.599  0.885  1.0
  Si  Si4  1  0.847  0.971  0.697  1.0
  P  P5  1  0.156  0.011  0.309  1.0
  P  P6  1  0.633  0.400  0.118  1.0
  P  P7  1  0.764  0.642  0.565  1.0
  P  P8  1  0.329  0.219  0.768  1.0
[/CIF]
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