The material described by KAsSe2 crystallizes in the triclinic P1 space group. There are four inequivalent K sites. In the first K site, K(1) is bonded in a 7-coordinate geometry to one Se(3), one Se(6), one Se(7), two equivalent Se(1), and two equivalent Se(4) atoms. In the second K site, K(2) is bonded in a 7-coordinate geometry to one As(2), one Se(1), one Se(5), one Se(6), one Se(8), and two equivalent Se(3) atoms. In the third K site, K(3) is bonded in a 7-coordinate geometry to one Se(2), one Se(3), one Se(7), two equivalent Se(5), and two equivalent Se(8) atoms. In the fourth K site, K(4) is bonded in a 7-coordinate geometry to one As(4), one Se(1), one Se(2), one Se(4), one Se(5), and two equivalent Se(7) atoms. There are four inequivalent As sites. In the first As site, As(1) is bonded in a distorted trigonal non-coplanar geometry to one Se(1), one Se(2), and one Se(4) atom. In the second As site, As(2) is bonded in a 4-coordinate geometry to one K(2), one Se(3), one Se(4), and one Se(6) atom. In the third As site, As(3) is bonded in a distorted trigonal non-coplanar geometry to one Se(5), one Se(6), and one Se(8) atom. In the fourth As site, As(4) is bonded in a 4-coordinate geometry to one K(4), one Se(2), one Se(7), and one Se(8) atom. There are eight inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to one K(2), one K(4), two equivalent K(1), and one As(1) atom. In the second Se site, Se(2) is bonded in a 4-coordinate geometry to one K(3), one K(4), one As(1), and one As(4) atom. In the third Se site, Se(3) is bonded to one K(1), one K(3), two equivalent K(2), and one As(2) atom to form distorted SeK4As trigonal bipyramids that share  a cornercorner with one Se(4)K3As2 square pyramid, corners with two equivalent Se(3)K4As trigonal bipyramids, corners with two equivalent Se(7)K4As trigonal bipyramids,  an edgeedge with one Se(4)K3As2 square pyramid, and edges with two equivalent Se(8)K3As2 square pyramids. In the fourth Se site, Se(4) is bonded to one K(4), two equivalent K(1), one As(1), and one As(2) atom to form distorted SeK3As2 square pyramids that share corners with two equivalent Se(4)K3As2 square pyramids,  a cornercorner with one Se(3)K4As trigonal bipyramid,  an edgeedge with one Se(3)K4As trigonal bipyramid, and edges with two equivalent Se(7)K4As trigonal bipyramids. In the fifth Se site, Se(5) is bonded in a 5-coordinate geometry to one K(2), one K(4), two equivalent K(3), and one As(3) atom. In the sixth Se site, Se(6) is bonded in a 4-coordinate geometry to one K(1), one K(2), one As(2), and one As(3) atom. In the seventh Se site, Se(7) is bonded to one K(1), one K(3), two equivalent K(4), and one As(4) atom to form distorted SeK4As trigonal bipyramids that share  a cornercorner with one Se(8)K3As2 square pyramid, corners with two equivalent Se(3)K4As trigonal bipyramids, corners with two equivalent Se(7)K4As trigonal bipyramids,  an edgeedge with one Se(8)K3As2 square pyramid, and edges with two equivalent Se(4)K3As2 square pyramids. In the eighth Se site, Se(8) is bonded to one K(2), two equivalent K(3), one As(3), and one As(4) atom to form distorted SeK3As2 square pyramids that share corners with two equivalent Se(8)K3As2 square pyramids,  a cornercorner with one Se(7)K4As trigonal bipyramid,  an edgeedge with one Se(7)K4As trigonal bipyramid, and edges with two equivalent Se(3)K4As trigonal bipyramids. is represented by the CIF file [CIF]
data_KAsSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.670
_cell_length_b   6.670
_cell_length_c   12.772
_cell_angle_alpha   100.390
_cell_angle_beta   100.449
_cell_angle_gamma   108.054
_symmetry_Int_Tables_number   1
_cell_volume   513.975
_cell_formula_units_Z   4
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  0.041  0.053  0.259  1.0
  K  K1  1  0.079  0.612  0.498  1.0
  K  K2  1  0.993  0.103  0.759  1.0
  K  K3  1  0.551  0.139  0.998  1.0
  As  As4  1  0.318  0.582  0.176  1.0
  As  As5  1  0.571  0.985  0.442  1.0
  As  As6  1  0.519  0.378  0.676  1.0
  As  As7  1  0.923  0.632  0.942  1.0
  Se  Se8  1  0.976  0.523  0.209  1.0
  Se  Se9  1  0.280  0.594  0.982  1.0
  Se  Se10  1  0.941  0.064  0.499  1.0
  Se  Se11  1  0.509  0.979  0.245  1.0
  Se  Se12  1  0.462  0.036  0.709  1.0
  Se  Se13  1  0.533  0.343  0.482  1.0
  Se  Se14  1  0.005  0.003  0.999  1.0
  Se  Se15  1  0.916  0.570  0.745  1.0
[/CIF]
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The material described by KAsSe2 crystallizes in the triclinic P1 space group. There are four inequivalent K sites. In the first K site, K(1) is bonded in a 7-coordinate geometry to one Se(3), one Se(6), one Se(7), two equivalent Se(1), and two equivalent Se(4) atoms. In the second K site, K(2) is bonded in a 7-coordinate geometry to one As(2), one Se(1), one Se(5), one Se(6), one Se(8), and two equivalent Se(3) atoms. In the third K site, K(3) is bonded in a 7-coordinate geometry to one Se(2), one Se(3), one Se(7), two equivalent Se(5), and two equivalent Se(8) atoms. In the fourth K site, K(4) is bonded in a 7-coordinate geometry to one As(4), one Se(1), one Se(2), one Se(4), one Se(5), and two equivalent Se(7) atoms. There are four inequivalent As sites. In the first As site, As(1) is bonded in a distorted trigonal non-coplanar geometry to one Se(1), one Se(2), and one Se(4) atom. In the second As site, As(2) is bonded in a 4-coordinate geometry to one K(2), one Se(3), one Se(4), and one Se(6) atom. In the third As site, As(3) is bonded in a distorted trigonal non-coplanar geometry to one Se(5), one Se(6), and one Se(8) atom. In the fourth As site, As(4) is bonded in a 4-coordinate geometry to one K(4), one Se(2), one Se(7), and one Se(8) atom. There are eight inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to one K(2), one K(4), two equivalent K(1), and one As(1) atom. In the second Se site, Se(2) is bonded in a 4-coordinate geometry to one K(3), one K(4), one As(1), and one As(4) atom. In the third Se site, Se(3) is bonded to one K(1), one K(3), two equivalent K(2), and one As(2) atom to form distorted SeK4As trigonal bipyramids that share  a cornercorner with one Se(4)K3As2 square pyramid, corners with two equivalent Se(3)K4As trigonal bipyramids, corners with two equivalent Se(7)K4As trigonal bipyramids,  an edgeedge with one Se(4)K3As2 square pyramid, and edges with two equivalent Se(8)K3As2 square pyramids. In the fourth Se site, Se(4) is bonded to one K(4), two equivalent K(1), one As(1), and one As(2) atom to form distorted SeK3As2 square pyramids that share corners with two equivalent Se(4)K3As2 square pyramids,  a cornercorner with one Se(3)K4As trigonal bipyramid,  an edgeedge with one Se(3)K4As trigonal bipyramid, and edges with two equivalent Se(7)K4As trigonal bipyramids. In the fifth Se site, Se(5) is bonded in a 5-coordinate geometry to one K(2), one K(4), two equivalent K(3), and one As(3) atom. In the sixth Se site, Se(6) is bonded in a 4-coordinate geometry to one K(1), one K(2), one As(2), and one As(3) atom. In the seventh Se site, Se(7) is bonded to one K(1), one K(3), two equivalent K(4), and one As(4) atom to form distorted SeK4As trigonal bipyramids that share  a cornercorner with one Se(8)K3As2 square pyramid, corners with two equivalent Se(3)K4As trigonal bipyramids, corners with two equivalent Se(7)K4As trigonal bipyramids,  an edgeedge with one Se(8)K3As2 square pyramid, and edges with two equivalent Se(4)K3As2 square pyramids. In the eighth Se site, Se(8) is bonded to one K(2), two equivalent K(3), one As(3), and one As(4) atom to form distorted SeK3As2 square pyramids that share corners with two equivalent Se(8)K3As2 square pyramids,  a cornercorner with one Se(7)K4As trigonal bipyramid,  an edgeedge with one Se(7)K4As trigonal bipyramid, and edges with two equivalent Se(3)K4As trigonal bipyramids. is represented by the CIF file [CIF]
data_KAsSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.670
_cell_length_b   6.670
_cell_length_c   12.772
_cell_angle_alpha   100.390
_cell_angle_beta   100.449
_cell_angle_gamma   108.054
_symmetry_Int_Tables_number   1
_cell_volume   513.975
_cell_formula_units_Z   4
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  0.041  0.053  0.259  1.0
  K  K1  1  0.079  0.612  0.498  1.0
  K  K2  1  0.993  0.103  0.759  1.0
  K  K3  1  0.551  0.139  0.998  1.0
  As  As4  1  0.318  0.582  0.176  1.0
  As  As5  1  0.571  0.985  0.442  1.0
  As  As6  1  0.519  0.378  0.676  1.0
  As  As7  1  0.923  0.632  0.942  1.0
  Se  Se8  1  0.976  0.523  0.209  1.0
  Se  Se9  1  0.280  0.594  0.982  1.0
  Se  Se10  1  0.941  0.064  0.499  1.0
  Se  Se11  1  0.509  0.979  0.245  1.0
  Se  Se12  1  0.462  0.036  0.709  1.0
  Se  Se13  1  0.533  0.343  0.482  1.0
  Se  Se14  1  0.005  0.003  0.999  1.0
  Se  Se15  1  0.916  0.570  0.745  1.0
[/CIF]
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