The material structure described by K2EuSiSe5 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 3-coordinate geometry to two equivalent Se(1) and four equivalent Se(4) atoms. In the second K site, K(2) is bonded in a 7-coordinate geometry to one Se(1), one Se(3), one Se(5), two equivalent Se(2), and two equivalent Se(4) atoms. Eu(1) is bonded in a 9-coordinate geometry to one Se(2), two equivalent Se(1), three equivalent Se(3), and three equivalent Se(5) atoms. Si(1) is bonded in a tetrahedral geometry to one Se(1), one Se(2), one Se(3), and one Se(4) atom. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to one K(2), two equivalent K(1), two equivalent Eu(1), and one Si(1) atom. In the second Se site, Se(2) is bonded in a 1-coordinate geometry to two equivalent K(2), one Eu(1), one Si(1), and one Se(5) atom. In the third Se site, Se(3) is bonded in a 1-coordinate geometry to one K(2), three equivalent Eu(1), one Si(1), and one Se(5) atom. In the fourth Se site, Se(4) is bonded in a 7-coordinate geometry to two equivalent K(2), four equivalent K(1), and one Si(1) atom. In the fifth Se site, Se(5) is bonded in a 6-coordinate geometry to one K(2), three equivalent Eu(1), one Se(2), and one Se(3) atom. is represented by the CIF file [CIF]
data_K2EuSiSe5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.969
_cell_length_b   9.060
_cell_length_c   11.879
_cell_angle_alpha   87.790
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1072.132
_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  0.200  0.544  0.938  1.0
  K  K1  1  0.942  0.873  0.801  1.0
  K  K2  1  0.558  0.373  0.801  1.0
  K  K3  1  0.800  0.456  0.062  1.0
  K  K4  1  0.300  0.044  0.938  1.0
  K  K5  1  0.700  0.956  0.062  1.0
  K  K6  1  0.442  0.627  0.199  1.0
  K  K7  1  0.058  0.127  0.199  1.0
  Eu  Eu8  1  0.229  0.604  0.517  1.0
  Eu  Eu9  1  0.271  0.104  0.517  1.0
  Eu  Eu10  1  0.729  0.896  0.483  1.0
  Eu  Eu11  1  0.771  0.396  0.483  1.0
  Si  Si12  1  0.478  0.791  0.747  1.0
  Si  Si13  1  0.522  0.209  0.253  1.0
  Si  Si14  1  0.022  0.291  0.747  1.0
  Si  Si15  1  0.978  0.709  0.253  1.0
  Se  Se16  1  0.241  0.352  0.712  1.0
  Se  Se17  1  0.624  0.992  0.755  1.0
  Se  Se18  1  0.964  0.144  0.599  1.0
  Se  Se19  1  0.376  0.008  0.245  1.0
  Se  Se20  1  0.464  0.356  0.401  1.0
  Se  Se21  1  0.487  0.309  0.077  1.0
  Se  Se22  1  0.259  0.852  0.712  1.0
  Se  Se23  1  0.436  0.839  0.415  1.0
  Se  Se24  1  0.036  0.856  0.401  1.0
  Se  Se25  1  0.013  0.809  0.077  1.0
  Se  Se26  1  0.513  0.691  0.923  1.0
  Se  Se27  1  0.759  0.648  0.288  1.0
  Se  Se28  1  0.124  0.508  0.245  1.0
  Se  Se29  1  0.936  0.661  0.585  1.0
  Se  Se30  1  0.741  0.148  0.288  1.0
  Se  Se31  1  0.564  0.161  0.585  1.0
  Se  Se32  1  0.987  0.191  0.923  1.0
  Se  Se33  1  0.064  0.339  0.415  1.0
  Se  Se34  1  0.536  0.644  0.599  1.0
  Se  Se35  1  0.876  0.492  0.755  1.0
[/CIF]
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The material structure described by K2EuSiSe5 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 3-coordinate geometry to two equivalent Se(1) and four equivalent Se(4) atoms. In the second K site, K(2) is bonded in a 7-coordinate geometry to one Se(1), one Se(3), one Se(5), two equivalent Se(2), and two equivalent Se(4) atoms. Eu(1) is bonded in a 9-coordinate geometry to one Se(2), two equivalent Se(1), three equivalent Se(3), and three equivalent Se(5) atoms. Si(1) is bonded in a tetrahedral geometry to one Se(1), one Se(2), one Se(3), and one Se(4) atom. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to one K(2), two equivalent K(1), two equivalent Eu(1), and one Si(1) atom. In the second Se site, Se(2) is bonded in a 1-coordinate geometry to two equivalent K(2), one Eu(1), one Si(1), and one Se(5) atom. In the third Se site, Se(3) is bonded in a 1-coordinate geometry to one K(2), three equivalent Eu(1), one Si(1), and one Se(5) atom. In the fourth Se site, Se(4) is bonded in a 7-coordinate geometry to two equivalent K(2), four equivalent K(1), and one Si(1) atom. In the fifth Se site, Se(5) is bonded in a 6-coordinate geometry to one K(2), three equivalent Eu(1), one Se(2), and one Se(3) atom. is represented by the CIF file [CIF]
data_K2EuSiSe5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.969
_cell_length_b   9.060
_cell_length_c   11.879
_cell_angle_alpha   87.790
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1072.132
_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  0.200  0.544  0.938  1.0
  K  K1  1  0.942  0.873  0.801  1.0
  K  K2  1  0.558  0.373  0.801  1.0
  K  K3  1  0.800  0.456  0.062  1.0
  K  K4  1  0.300  0.044  0.938  1.0
  K  K5  1  0.700  0.956  0.062  1.0
  K  K6  1  0.442  0.627  0.199  1.0
  K  K7  1  0.058  0.127  0.199  1.0
  Eu  Eu8  1  0.229  0.604  0.517  1.0
  Eu  Eu9  1  0.271  0.104  0.517  1.0
  Eu  Eu10  1  0.729  0.896  0.483  1.0
  Eu  Eu11  1  0.771  0.396  0.483  1.0
  Si  Si12  1  0.478  0.791  0.747  1.0
  Si  Si13  1  0.522  0.209  0.253  1.0
  Si  Si14  1  0.022  0.291  0.747  1.0
  Si  Si15  1  0.978  0.709  0.253  1.0
  Se  Se16  1  0.241  0.352  0.712  1.0
  Se  Se17  1  0.624  0.992  0.755  1.0
  Se  Se18  1  0.964  0.144  0.599  1.0
  Se  Se19  1  0.376  0.008  0.245  1.0
  Se  Se20  1  0.464  0.356  0.401  1.0
  Se  Se21  1  0.487  0.309  0.077  1.0
  Se  Se22  1  0.259  0.852  0.712  1.0
  Se  Se23  1  0.436  0.839  0.415  1.0
  Se  Se24  1  0.036  0.856  0.401  1.0
  Se  Se25  1  0.013  0.809  0.077  1.0
  Se  Se26  1  0.513  0.691  0.923  1.0
  Se  Se27  1  0.759  0.648  0.288  1.0
  Se  Se28  1  0.124  0.508  0.245  1.0
  Se  Se29  1  0.936  0.661  0.585  1.0
  Se  Se30  1  0.741  0.148  0.288  1.0
  Se  Se31  1  0.564  0.161  0.585  1.0
  Se  Se32  1  0.987  0.191  0.923  1.0
  Se  Se33  1  0.064  0.339  0.415  1.0
  Se  Se34  1  0.536  0.644  0.599  1.0
  Se  Se35  1  0.876  0.492  0.755  1.0
[/CIF]
.