The material described by FeCoAs4 crystallizes in the monoclinic P2/m space group. Fe(1) is bonded to two equivalent As(2) and four equivalent As(1) atoms to form FeAs6 octahedra that share corners with eight equivalent Co(1)As6 octahedra and edges with two equivalent Fe(1)As6 octahedra. The corner-sharing octahedral tilt angles range from 53-54°. Co(1) is bonded to two equivalent As(1) and four equivalent As(2) atoms to form CoAs6 octahedra that share corners with eight equivalent Fe(1)As6 octahedra and edges with two equivalent Co(1)As6 octahedra. The corner-sharing octahedral tilt angles range from 53-54°. There are two inequivalent As sites. In the first As site, As(1) is bonded in a 3-coordinate geometry to two equivalent Fe(1) and one Co(1) atom. In the second As site, As(2) is bonded in a 3-coordinate geometry to one Fe(1) and two equivalent Co(1) atoms. is represented by the CIF card [CIF]
data_FeCoAs4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.976
_cell_length_b   5.186
_cell_length_c   5.931
_cell_angle_alpha   89.925
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   91.526
_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  0.500  1.0
  As  As2  1  0.500  0.317  0.133  1.0
  As  As3  1  0.500  0.683  0.867  1.0
  As  As4  1  0.000  0.820  0.361  1.0
  As  As5  1  0.000  0.180  0.639  1.0
[/CIF]
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The material described by FeCoAs4 crystallizes in the monoclinic P2/m space group. Fe(1) is bonded to two equivalent As(2) and four equivalent As(1) atoms to form FeAs6 octahedra that share corners with eight equivalent Co(1)As6 octahedra and edges with two equivalent Fe(1)As6 octahedra. The corner-sharing octahedral tilt angles range from 53-54°. Co(1) is bonded to two equivalent As(1) and four equivalent As(2) atoms to form CoAs6 octahedra that share corners with eight equivalent Fe(1)As6 octahedra and edges with two equivalent Co(1)As6 octahedra. The corner-sharing octahedral tilt angles range from 53-54°. There are two inequivalent As sites. In the first As site, As(1) is bonded in a 3-coordinate geometry to two equivalent Fe(1) and one Co(1) atom. In the second As site, As(2) is bonded in a 3-coordinate geometry to one Fe(1) and two equivalent Co(1) atoms. is represented by the CIF card [CIF]
data_FeCoAs4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.976
_cell_length_b   5.186
_cell_length_c   5.931
_cell_angle_alpha   89.925
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   91.526
_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  0.500  1.0
  As  As2  1  0.500  0.317  0.133  1.0
  As  As3  1  0.500  0.683  0.867  1.0
  As  As4  1  0.000  0.820  0.361  1.0
  As  As5  1  0.000  0.180  0.639  1.0
[/CIF]
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