The material described by K4Sr2SnAs4 crystallizes in the monoclinic Cc space group. There are four inequivalent K sites. In the first K site, K(1) is bonded in a 3-coordinate geometry to one As(1), one As(2), one As(3), and two equivalent As(4) atoms. In the second K site, K(2) is bonded in a 4-coordinate geometry to one As(1), one As(4), and two equivalent As(3) atoms. In the third K site, K(3) is bonded in a 4-coordinate geometry to one As(1), one As(4), and two equivalent As(2) atoms. In the fourth K site, K(4) is bonded in a 4-coordinate geometry to one As(1), one As(2), one As(3), and one As(4) atom. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 3-coordinate geometry to one As(1), one As(2), one As(3), and two equivalent As(4) atoms. In the second Sr site, Sr(2) is bonded in a 3-coordinate geometry to one As(1), two equivalent As(2), and two equivalent As(3) atoms. Sn(1) is bonded in a distorted tetrahedral geometry to one As(1), one As(2), one As(3), and one As(4) atom. There are four inequivalent As sites. In the first As site, As(4) is bonded in a 8-coordinate geometry to one K(2), one K(3), one K(4), two equivalent K(1), two equivalent Sr(1), and one Sn(1) atom. In the second As site, As(1) is bonded in a 7-coordinate geometry to one K(1), one K(2), one K(3), one K(4), one Sr(1), one Sr(2), and one Sn(1) atom. In the third As site, As(2) is bonded in a 8-coordinate geometry to one K(1), one K(4), two equivalent K(3), one Sr(1), two equivalent Sr(2), and one Sn(1) atom. In the fourth As site, As(3) is bonded in a 8-coordinate geometry to one K(1), one K(4), two equivalent K(2), one Sr(1), two equivalent Sr(2), and one Sn(1) atom. is represented by the CIF file [CIF]
data_K4Sr2SnAs4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.546
_cell_length_b   10.546
_cell_length_c   7.768
_cell_angle_alpha   88.691
_cell_angle_beta   88.691
_cell_angle_gamma   119.462
_symmetry_Int_Tables_number   1
_cell_volume   751.484
_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  0.477  0.950  0.381  1.0
  K  K1  1  0.950  0.477  0.881  1.0
  K  K2  1  0.860  0.716  0.181  1.0
  K  K3  1  0.285  0.137  0.211  1.0
  K  K4  1  0.851  0.140  0.194  1.0
  K  K5  1  0.137  0.285  0.711  1.0
  K  K6  1  0.716  0.860  0.681  1.0
  K  K7  1  0.140  0.851  0.694  1.0
  Sr  Sr8  1  0.060  0.530  0.382  1.0
  Sr  Sr9  1  0.477  0.529  0.380  1.0
  Sr  Sr10  1  0.530  0.060  0.882  1.0
  Sr  Sr11  1  0.529  0.477  0.880  1.0
  Sn  Sn12  1  0.664  0.332  0.497  1.0
  Sn  Sn13  1  0.332  0.664  0.997  1.0
  As  As14  1  0.655  0.333  0.151  1.0
  As  As15  1  0.333  0.655  0.651  1.0
  As  As16  1  0.204  0.392  0.135  1.0
  As  As17  1  0.608  0.796  0.092  1.0
  As  As18  1  0.198  0.806  0.109  1.0
  As  As19  1  0.796  0.608  0.592  1.0
  As  As20  1  0.392  0.204  0.635  1.0
  As  As21  1  0.806  0.198  0.609  1.0
[/CIF]
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The material described by K4Sr2SnAs4 crystallizes in the monoclinic Cc space group. There are four inequivalent K sites. In the first K site, K(1) is bonded in a 3-coordinate geometry to one As(1), one As(2), one As(3), and two equivalent As(4) atoms. In the second K site, K(2) is bonded in a 4-coordinate geometry to one As(1), one As(4), and two equivalent As(3) atoms. In the third K site, K(3) is bonded in a 4-coordinate geometry to one As(1), one As(4), and two equivalent As(2) atoms. In the fourth K site, K(4) is bonded in a 4-coordinate geometry to one As(1), one As(2), one As(3), and one As(4) atom. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 3-coordinate geometry to one As(1), one As(2), one As(3), and two equivalent As(4) atoms. In the second Sr site, Sr(2) is bonded in a 3-coordinate geometry to one As(1), two equivalent As(2), and two equivalent As(3) atoms. Sn(1) is bonded in a distorted tetrahedral geometry to one As(1), one As(2), one As(3), and one As(4) atom. There are four inequivalent As sites. In the first As site, As(4) is bonded in a 8-coordinate geometry to one K(2), one K(3), one K(4), two equivalent K(1), two equivalent Sr(1), and one Sn(1) atom. In the second As site, As(1) is bonded in a 7-coordinate geometry to one K(1), one K(2), one K(3), one K(4), one Sr(1), one Sr(2), and one Sn(1) atom. In the third As site, As(2) is bonded in a 8-coordinate geometry to one K(1), one K(4), two equivalent K(3), one Sr(1), two equivalent Sr(2), and one Sn(1) atom. In the fourth As site, As(3) is bonded in a 8-coordinate geometry to one K(1), one K(4), two equivalent K(2), one Sr(1), two equivalent Sr(2), and one Sn(1) atom. is represented by the CIF file [CIF]
data_K4Sr2SnAs4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.546
_cell_length_b   10.546
_cell_length_c   7.768
_cell_angle_alpha   88.691
_cell_angle_beta   88.691
_cell_angle_gamma   119.462
_symmetry_Int_Tables_number   1
_cell_volume   751.484
_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  0.477  0.950  0.381  1.0
  K  K1  1  0.950  0.477  0.881  1.0
  K  K2  1  0.860  0.716  0.181  1.0
  K  K3  1  0.285  0.137  0.211  1.0
  K  K4  1  0.851  0.140  0.194  1.0
  K  K5  1  0.137  0.285  0.711  1.0
  K  K6  1  0.716  0.860  0.681  1.0
  K  K7  1  0.140  0.851  0.694  1.0
  Sr  Sr8  1  0.060  0.530  0.382  1.0
  Sr  Sr9  1  0.477  0.529  0.380  1.0
  Sr  Sr10  1  0.530  0.060  0.882  1.0
  Sr  Sr11  1  0.529  0.477  0.880  1.0
  Sn  Sn12  1  0.664  0.332  0.497  1.0
  Sn  Sn13  1  0.332  0.664  0.997  1.0
  As  As14  1  0.655  0.333  0.151  1.0
  As  As15  1  0.333  0.655  0.651  1.0
  As  As16  1  0.204  0.392  0.135  1.0
  As  As17  1  0.608  0.796  0.092  1.0
  As  As18  1  0.198  0.806  0.109  1.0
  As  As19  1  0.796  0.608  0.592  1.0
  As  As20  1  0.392  0.204  0.635  1.0
  As  As21  1  0.806  0.198  0.609  1.0
[/CIF]
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