The crystal structure described by K3AlSe3 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent K sites. In the first K site, K(1) is bonded in a 6-coordinate geometry to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms. In the second K site, K(2) is bonded in a 5-coordinate geometry to one Se(1), two equivalent Se(2), and two equivalent Se(3) atoms. In the third K site, K(3) is bonded in a 4-coordinate geometry to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms. Al(1) is bonded to one Se(2), one Se(3), and two equivalent Se(1) atoms to form edge-sharing AlSe4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 7-coordinate geometry to one K(2), two equivalent K(1), two equivalent K(3), and two equivalent Al(1) atoms. In the second Se site, Se(2) is bonded in a 7-coordinate geometry to two equivalent K(1), two equivalent K(2), two equivalent K(3), and one Al(1) atom. In the third Se site, Se(3) is bonded in a 1-coordinate geometry to two equivalent K(1), two equivalent K(2), two equivalent K(3), and one Al(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K3AlSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.102
_cell_length_b   8.107
_cell_length_c   10.466
_cell_angle_alpha   52.411
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   880.829
_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  0.312  0.151  0.074  1.0
  K  K1  1  0.688  0.849  0.926  1.0
  K  K2  1  0.812  0.849  0.426  1.0
  K  K3  1  0.898  0.322  0.398  1.0
  K  K4  1  0.619  0.378  0.470  1.0
  K  K5  1  0.119  0.622  0.030  1.0
  K  K6  1  0.381  0.622  0.530  1.0
  K  K7  1  0.881  0.378  0.970  1.0
  K  K8  1  0.602  0.322  0.898  1.0
  K  K9  1  0.102  0.678  0.602  1.0
  K  K10  1  0.398  0.678  0.102  1.0
  K  K11  1  0.188  0.151  0.574  1.0
  Al  Al12  1  0.062  0.943  0.158  1.0
  Al  Al13  1  0.562  0.057  0.342  1.0
  Al  Al14  1  0.438  0.943  0.658  1.0
  Al  Al15  1  0.938  0.057  0.842  1.0
  Se  Se16  1  0.398  0.171  0.370  1.0
  Se  Se17  1  0.898  0.829  0.130  1.0
  Se  Se18  1  0.602  0.829  0.630  1.0
  Se  Se19  1  0.102  0.171  0.870  1.0
  Se  Se20  1  0.686  0.326  0.198  1.0
  Se  Se21  1  0.186  0.674  0.302  1.0
  Se  Se22  1  0.314  0.674  0.802  1.0
  Se  Se23  1  0.814  0.326  0.698  1.0
  Se  Se24  1  0.548  0.870  0.237  1.0
  Se  Se25  1  0.048  0.130  0.263  1.0
  Se  Se26  1  0.452  0.130  0.763  1.0
  Se  Se27  1  0.952  0.870  0.737  1.0
[/CIF]
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The crystal structure described by K3AlSe3 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent K sites. In the first K site, K(1) is bonded in a 6-coordinate geometry to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms. In the second K site, K(2) is bonded in a 5-coordinate geometry to one Se(1), two equivalent Se(2), and two equivalent Se(3) atoms. In the third K site, K(3) is bonded in a 4-coordinate geometry to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms. Al(1) is bonded to one Se(2), one Se(3), and two equivalent Se(1) atoms to form edge-sharing AlSe4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 7-coordinate geometry to one K(2), two equivalent K(1), two equivalent K(3), and two equivalent Al(1) atoms. In the second Se site, Se(2) is bonded in a 7-coordinate geometry to two equivalent K(1), two equivalent K(2), two equivalent K(3), and one Al(1) atom. In the third Se site, Se(3) is bonded in a 1-coordinate geometry to two equivalent K(1), two equivalent K(2), two equivalent K(3), and one Al(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K3AlSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.102
_cell_length_b   8.107
_cell_length_c   10.466
_cell_angle_alpha   52.411
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   880.829
_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  0.312  0.151  0.074  1.0
  K  K1  1  0.688  0.849  0.926  1.0
  K  K2  1  0.812  0.849  0.426  1.0
  K  K3  1  0.898  0.322  0.398  1.0
  K  K4  1  0.619  0.378  0.470  1.0
  K  K5  1  0.119  0.622  0.030  1.0
  K  K6  1  0.381  0.622  0.530  1.0
  K  K7  1  0.881  0.378  0.970  1.0
  K  K8  1  0.602  0.322  0.898  1.0
  K  K9  1  0.102  0.678  0.602  1.0
  K  K10  1  0.398  0.678  0.102  1.0
  K  K11  1  0.188  0.151  0.574  1.0
  Al  Al12  1  0.062  0.943  0.158  1.0
  Al  Al13  1  0.562  0.057  0.342  1.0
  Al  Al14  1  0.438  0.943  0.658  1.0
  Al  Al15  1  0.938  0.057  0.842  1.0
  Se  Se16  1  0.398  0.171  0.370  1.0
  Se  Se17  1  0.898  0.829  0.130  1.0
  Se  Se18  1  0.602  0.829  0.630  1.0
  Se  Se19  1  0.102  0.171  0.870  1.0
  Se  Se20  1  0.686  0.326  0.198  1.0
  Se  Se21  1  0.186  0.674  0.302  1.0
  Se  Se22  1  0.314  0.674  0.802  1.0
  Se  Se23  1  0.814  0.326  0.698  1.0
  Se  Se24  1  0.548  0.870  0.237  1.0
  Se  Se25  1  0.048  0.130  0.263  1.0
  Se  Se26  1  0.452  0.130  0.763  1.0
  Se  Se27  1  0.952  0.870  0.737  1.0
[/CIF]
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