The compound described by K3Al2As3 crystallizes in the monoclinic P2_1/m space group. There are three inequivalent K sites. In the first K site, K(1) is bonded in a 5-coordinate geometry to one As(2), one As(3), and three equivalent As(1) atoms. In the second K site, K(2) is bonded in a 4-coordinate geometry to one As(2) and three equivalent As(3) atoms. In the third K site, K(3) is bonded in a 5-coordinate geometry to one As(1), one As(3), and three equivalent As(2) atoms. Al(1) is bonded to one As(2), one As(3), and two equivalent As(1) atoms to form a mixture of corner and edge-sharing AlAs4 tetrahedra. There are three inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to one K(3), three equivalent K(1), and four equivalent Al(1) atoms. In the second As site, As(2) is bonded in a 7-coordinate geometry to one K(1), one K(2), three equivalent K(3), and two equivalent Al(1) atoms. In the third As site, As(3) is bonded in a 7-coordinate geometry to one K(1), one K(3), three equivalent K(2), and two equivalent Al(1) atoms. is represented by the CIF file [CIF]
data_K3Al2As3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.003
_cell_length_b   7.578
_cell_length_c   10.517
_cell_angle_alpha   110.304
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   448.705
_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  0.564  0.427  1.0
  K  K1  1  0.750  0.871  0.922  1.0
  K  K2  1  0.750  0.523  0.149  1.0
  K  K3  1  0.250  0.477  0.851  1.0
  K  K4  1  0.750  0.436  0.573  1.0
  K  K5  1  0.250  0.129  0.078  1.0
  Al  Al6  1  1.000  0.972  0.343  1.0
  Al  Al7  1  0.500  0.028  0.657  1.0
  Al  Al8  1  0.500  0.972  0.343  1.0
  Al  Al9  1  0.000  0.028  0.657  1.0
  As  As10  1  0.250  0.188  0.530  1.0
  As  As11  1  0.750  0.812  0.470  1.0
  As  As12  1  0.250  0.746  0.182  1.0
  As  As13  1  0.750  0.254  0.818  1.0
  As  As14  1  0.250  0.847  0.748  1.0
  As  As15  1  0.750  0.153  0.252  1.0
[/CIF]
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The compound described by K3Al2As3 crystallizes in the monoclinic P2_1/m space group. There are three inequivalent K sites. In the first K site, K(1) is bonded in a 5-coordinate geometry to one As(2), one As(3), and three equivalent As(1) atoms. In the second K site, K(2) is bonded in a 4-coordinate geometry to one As(2) and three equivalent As(3) atoms. In the third K site, K(3) is bonded in a 5-coordinate geometry to one As(1), one As(3), and three equivalent As(2) atoms. Al(1) is bonded to one As(2), one As(3), and two equivalent As(1) atoms to form a mixture of corner and edge-sharing AlAs4 tetrahedra. There are three inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to one K(3), three equivalent K(1), and four equivalent Al(1) atoms. In the second As site, As(2) is bonded in a 7-coordinate geometry to one K(1), one K(2), three equivalent K(3), and two equivalent Al(1) atoms. In the third As site, As(3) is bonded in a 7-coordinate geometry to one K(1), one K(3), three equivalent K(2), and two equivalent Al(1) atoms. is represented by the CIF file [CIF]
data_K3Al2As3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.003
_cell_length_b   7.578
_cell_length_c   10.517
_cell_angle_alpha   110.304
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   448.705
_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  0.564  0.427  1.0
  K  K1  1  0.750  0.871  0.922  1.0
  K  K2  1  0.750  0.523  0.149  1.0
  K  K3  1  0.250  0.477  0.851  1.0
  K  K4  1  0.750  0.436  0.573  1.0
  K  K5  1  0.250  0.129  0.078  1.0
  Al  Al6  1  1.000  0.972  0.343  1.0
  Al  Al7  1  0.500  0.028  0.657  1.0
  Al  Al8  1  0.500  0.972  0.343  1.0
  Al  Al9  1  0.000  0.028  0.657  1.0
  As  As10  1  0.250  0.188  0.530  1.0
  As  As11  1  0.750  0.812  0.470  1.0
  As  As12  1  0.250  0.746  0.182  1.0
  As  As13  1  0.750  0.254  0.818  1.0
  As  As14  1  0.250  0.847  0.748  1.0
  As  As15  1  0.750  0.153  0.252  1.0
[/CIF]
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