The compound described by FeCo3 is alpha La-derived structured and crystallizes in the tetragonal P4/mmm space group. Fe(1) is bonded to four equivalent Fe(1) and eight equivalent Co(1) atoms to form FeFe4Co8 cuboctahedra that share corners with four equivalent Fe(1)Fe4Co8 cuboctahedra, corners with eight equivalent Co(2)Co12 cuboctahedra, edges with eight equivalent Co(2)Co12 cuboctahedra, edges with sixteen equivalent Co(1)Fe4Co8 cuboctahedra, faces with two equivalent Co(2)Co12 cuboctahedra, faces with eight equivalent Fe(1)Fe4Co8 cuboctahedra, and faces with eight equivalent Co(1)Fe4Co8 cuboctahedra. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to four equivalent Fe(1), four equivalent Co(1), and four equivalent Co(2) atoms to form CoFe4Co8 cuboctahedra that share corners with twelve equivalent Co(1)Fe4Co8 cuboctahedra, edges with eight equivalent Fe(1)Fe4Co8 cuboctahedra, edges with eight equivalent Co(2)Co12 cuboctahedra, edges with eight equivalent Co(1)Fe4Co8 cuboctahedra, faces with four equivalent Fe(1)Fe4Co8 cuboctahedra, faces with four equivalent Co(2)Co12 cuboctahedra, and faces with ten equivalent Co(1)Fe4Co8 cuboctahedra. In the second Co site, Co(2) is bonded to four equivalent Co(2) and eight equivalent Co(1) atoms to form CoCo12 cuboctahedra that share corners with four equivalent Co(2)Co12 cuboctahedra, corners with eight equivalent Fe(1)Fe4Co8 cuboctahedra, edges with eight equivalent Fe(1)Fe4Co8 cuboctahedra, edges with sixteen equivalent Co(1)Fe4Co8 cuboctahedra, faces with two equivalent Fe(1)Fe4Co8 cuboctahedra, faces with eight equivalent Co(2)Co12 cuboctahedra, and faces with eight equivalent Co(1)Fe4Co8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_FeCo3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.466
_cell_length_b   2.466
_cell_length_c   7.063
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   42.954
_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
  Co  Co1  1  0.500  0.500  0.745  1.0
  Co  Co2  1  0.000  0.000  0.500  1.0
  Co  Co3  1  0.500  0.500  0.255  1.0
[/CIF]
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The compound described by FeCo3 is alpha La-derived structured and crystallizes in the tetragonal P4/mmm space group. Fe(1) is bonded to four equivalent Fe(1) and eight equivalent Co(1) atoms to form FeFe4Co8 cuboctahedra that share corners with four equivalent Fe(1)Fe4Co8 cuboctahedra, corners with eight equivalent Co(2)Co12 cuboctahedra, edges with eight equivalent Co(2)Co12 cuboctahedra, edges with sixteen equivalent Co(1)Fe4Co8 cuboctahedra, faces with two equivalent Co(2)Co12 cuboctahedra, faces with eight equivalent Fe(1)Fe4Co8 cuboctahedra, and faces with eight equivalent Co(1)Fe4Co8 cuboctahedra. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to four equivalent Fe(1), four equivalent Co(1), and four equivalent Co(2) atoms to form CoFe4Co8 cuboctahedra that share corners with twelve equivalent Co(1)Fe4Co8 cuboctahedra, edges with eight equivalent Fe(1)Fe4Co8 cuboctahedra, edges with eight equivalent Co(2)Co12 cuboctahedra, edges with eight equivalent Co(1)Fe4Co8 cuboctahedra, faces with four equivalent Fe(1)Fe4Co8 cuboctahedra, faces with four equivalent Co(2)Co12 cuboctahedra, and faces with ten equivalent Co(1)Fe4Co8 cuboctahedra. In the second Co site, Co(2) is bonded to four equivalent Co(2) and eight equivalent Co(1) atoms to form CoCo12 cuboctahedra that share corners with four equivalent Co(2)Co12 cuboctahedra, corners with eight equivalent Fe(1)Fe4Co8 cuboctahedra, edges with eight equivalent Fe(1)Fe4Co8 cuboctahedra, edges with sixteen equivalent Co(1)Fe4Co8 cuboctahedra, faces with two equivalent Fe(1)Fe4Co8 cuboctahedra, faces with eight equivalent Co(2)Co12 cuboctahedra, and faces with eight equivalent Co(1)Fe4Co8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_FeCo3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.466
_cell_length_b   2.466
_cell_length_c   7.063
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   42.954
_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
  Co  Co1  1  0.500  0.500  0.745  1.0
  Co  Co2  1  0.000  0.000  0.500  1.0
  Co  Co3  1  0.500  0.500  0.255  1.0
[/CIF]
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