The compound described by KFeSe2 crystallizes in the monoclinic C2/c space group. K(1) is bonded to eight equivalent Se(1) atoms to form distorted KSe8 hexagonal bipyramids that share corners with four equivalent K(1)Se8 hexagonal bipyramids, corners with six equivalent Fe(1)Se4 tetrahedra, edges with six equivalent K(1)Se8 hexagonal bipyramids, edges with five equivalent Fe(1)Se4 tetrahedra, and faces with two equivalent K(1)Se8 hexagonal bipyramids. Fe(1) is bonded to four equivalent Se(1) atoms to form FeSe4 tetrahedra that share corners with six equivalent K(1)Se8 hexagonal bipyramids, edges with five equivalent K(1)Se8 hexagonal bipyramids, and edges with two equivalent Fe(1)Se4 tetrahedra. Se(1) is bonded in a 6-coordinate geometry to four equivalent K(1) and two equivalent Fe(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_KFeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.550
_cell_length_b   6.812
_cell_length_c   6.812
_cell_angle_alpha   114.859
_cell_angle_beta   101.833
_cell_angle_gamma   101.833
_symmetry_Int_Tables_number   1
_cell_volume   216.049
_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
  K  K0  1  0.250  0.363  0.637  1.0
  K  K1  1  0.750  0.637  0.363  1.0
  Fe  Fe2  1  0.250  0.996  0.004  1.0
  Fe  Fe3  1  0.750  0.004  0.996  1.0
  Se  Se4  1  0.895  0.686  0.915  1.0
  Se  Se5  1  0.605  0.085  0.314  1.0
  Se  Se6  1  0.105  0.314  0.085  1.0
  Se  Se7  1  0.395  0.915  0.686  1.0
[/CIF]
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The compound described by KFeSe2 crystallizes in the monoclinic C2/c space group. K(1) is bonded to eight equivalent Se(1) atoms to form distorted KSe8 hexagonal bipyramids that share corners with four equivalent K(1)Se8 hexagonal bipyramids, corners with six equivalent Fe(1)Se4 tetrahedra, edges with six equivalent K(1)Se8 hexagonal bipyramids, edges with five equivalent Fe(1)Se4 tetrahedra, and faces with two equivalent K(1)Se8 hexagonal bipyramids. Fe(1) is bonded to four equivalent Se(1) atoms to form FeSe4 tetrahedra that share corners with six equivalent K(1)Se8 hexagonal bipyramids, edges with five equivalent K(1)Se8 hexagonal bipyramids, and edges with two equivalent Fe(1)Se4 tetrahedra. Se(1) is bonded in a 6-coordinate geometry to four equivalent K(1) and two equivalent Fe(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_KFeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.550
_cell_length_b   6.812
_cell_length_c   6.812
_cell_angle_alpha   114.859
_cell_angle_beta   101.833
_cell_angle_gamma   101.833
_symmetry_Int_Tables_number   1
_cell_volume   216.049
_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
  K  K0  1  0.250  0.363  0.637  1.0
  K  K1  1  0.750  0.637  0.363  1.0
  Fe  Fe2  1  0.250  0.996  0.004  1.0
  Fe  Fe3  1  0.750  0.004  0.996  1.0
  Se  Se4  1  0.895  0.686  0.915  1.0
  Se  Se5  1  0.605  0.085  0.314  1.0
  Se  Se6  1  0.105  0.314  0.085  1.0
  Se  Se7  1  0.395  0.915  0.686  1.0
[/CIF]
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