The compound described by CoAsSe is Marcasite-derived structured and crystallizes in the monoclinic P2/m space group. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent As(1) and four equivalent Se(1) atoms to form CoAs2Se4 octahedra that share corners with eight equivalent Co(2)As4Se2 octahedra, corners with two equivalent As(1)Co3As tetrahedra, and edges with two equivalent Co(1)As2Se4 octahedra. The corner-sharing octahedral tilt angles are 57°. In the second Co site, Co(2) is bonded to four equivalent As(1) and two equivalent Se(1) atoms to form CoAs4Se2 octahedra that share corners with eight equivalent Co(1)As2Se4 octahedra, corners with four equivalent As(1)Co3As tetrahedra, and edges with two equivalent Co(2)As4Se2 octahedra. The corner-sharing octahedral tilt angles are 57°. As(1) is bonded to one Co(1), two equivalent Co(2), and one As(1) atom to form distorted AsCo3As tetrahedra that share  a cornercorner with one Co(1)As2Se4 octahedra, corners with two equivalent Co(2)As4Se2 octahedra, corners with five equivalent As(1)Co3As tetrahedra, and  an edgeedge with one As(1)Co3As tetrahedra. The corner-sharing octahedral tilt angles range from 73-79°. Se(1) is bonded in a 3-coordinate geometry to one Co(2) and two equivalent Co(1) atoms. is represented by the CIF card [CIF]
data_CoAsSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.561
_cell_length_b   4.834
_cell_length_c   5.788
_cell_angle_alpha   88.730
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   99.627
_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
  Co  Co0  1  0.500  0.500  0.500  1.0
  Co  Co1  1  0.000  0.000  0.000  1.0
  As  As2  1  0.500  0.292  0.129  1.0
  As  As3  1  0.500  0.708  0.871  1.0
  Se  Se4  1  0.000  0.784  0.363  1.0
  Se  Se5  1  0.000  0.216  0.637  1.0
[/CIF]
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The compound described by CoAsSe is Marcasite-derived structured and crystallizes in the monoclinic P2/m space group. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent As(1) and four equivalent Se(1) atoms to form CoAs2Se4 octahedra that share corners with eight equivalent Co(2)As4Se2 octahedra, corners with two equivalent As(1)Co3As tetrahedra, and edges with two equivalent Co(1)As2Se4 octahedra. The corner-sharing octahedral tilt angles are 57°. In the second Co site, Co(2) is bonded to four equivalent As(1) and two equivalent Se(1) atoms to form CoAs4Se2 octahedra that share corners with eight equivalent Co(1)As2Se4 octahedra, corners with four equivalent As(1)Co3As tetrahedra, and edges with two equivalent Co(2)As4Se2 octahedra. The corner-sharing octahedral tilt angles are 57°. As(1) is bonded to one Co(1), two equivalent Co(2), and one As(1) atom to form distorted AsCo3As tetrahedra that share  a cornercorner with one Co(1)As2Se4 octahedra, corners with two equivalent Co(2)As4Se2 octahedra, corners with five equivalent As(1)Co3As tetrahedra, and  an edgeedge with one As(1)Co3As tetrahedra. The corner-sharing octahedral tilt angles range from 73-79°. Se(1) is bonded in a 3-coordinate geometry to one Co(2) and two equivalent Co(1) atoms. is represented by the CIF card [CIF]
data_CoAsSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.561
_cell_length_b   4.834
_cell_length_c   5.788
_cell_angle_alpha   88.730
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   99.627
_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
  Co  Co0  1  0.500  0.500  0.500  1.0
  Co  Co1  1  0.000  0.000  0.000  1.0
  As  As2  1  0.500  0.292  0.129  1.0
  As  As3  1  0.500  0.708  0.871  1.0
  Se  Se4  1  0.000  0.784  0.363  1.0
  Se  Se5  1  0.000  0.216  0.637  1.0
[/CIF]
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