The material described by K2MnSnSe4 crystallizes in the tetragonal P-4n2 space group. There are three inequivalent K sites. In the first K site, K(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. In the second K site, K(2) is bonded in a distorted square co-planar geometry to four equivalent Se(2) atoms. In the third K site, K(3) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to four equivalent Se(1) atoms to form distorted MnSe4 trigonal pyramids that share corners with four equivalent Sn(1)Se4 tetrahedra. In the second Mn site, Mn(2) is bonded to four equivalent Se(2) atoms to form distorted MnSe4 tetrahedra that share edges with two equivalent Sn(1)Se4 tetrahedra. Sn(1) is bonded to two equivalent Se(1) and two equivalent Se(2) atoms to form SnSe4 tetrahedra that share corners with two equivalent Mn(1)Se4 trigonal pyramids and  an edgeedge with one Mn(2)Se4 tetrahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to one K(3), two equivalent K(1), one Mn(1), and one Sn(1) atom. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to one K(2), one K(3), two equivalent K(1), one Mn(2), and one Sn(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K2MnSnSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.658
_cell_length_b   10.658
_cell_length_c   8.356
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   949.227
_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  0.253  0.753  0.750  1.0
  K  K1  1  0.500  0.500  0.500  1.0
  K  K2  1  0.000  0.000  0.000  1.0
  K  K3  1  0.747  0.247  0.750  1.0
  K  K4  1  0.000  0.500  0.250  1.0
  K  K5  1  0.500  0.000  0.750  1.0
  K  K6  1  0.247  0.253  0.250  1.0
  K  K7  1  0.753  0.747  0.250  1.0
  Mn  Mn8  1  0.500  0.500  0.000  1.0
  Mn  Mn9  1  0.000  0.000  0.500  1.0
  Mn  Mn10  1  0.000  0.500  0.750  1.0
  Mn  Mn11  1  0.500  0.000  0.250  1.0
  Sn  Sn12  1  0.279  0.779  0.250  1.0
  Sn  Sn13  1  0.721  0.221  0.250  1.0
  Sn  Sn14  1  0.221  0.279  0.750  1.0
  Sn  Sn15  1  0.779  0.721  0.750  1.0
  Se  Se16  1  0.288  0.568  0.109  1.0
  Se  Se17  1  0.971  0.695  0.929  1.0
  Se  Se18  1  0.471  0.805  0.429  1.0
  Se  Se19  1  0.712  0.432  0.109  1.0
  Se  Se20  1  0.029  0.305  0.929  1.0
  Se  Se21  1  0.695  0.029  0.071  1.0
  Se  Se22  1  0.529  0.195  0.429  1.0
  Se  Se23  1  0.805  0.529  0.571  1.0
  Se  Se24  1  0.212  0.068  0.609  1.0
  Se  Se25  1  0.788  0.932  0.609  1.0
  Se  Se26  1  0.195  0.471  0.571  1.0
  Se  Se27  1  0.568  0.712  0.891  1.0
  Se  Se28  1  0.432  0.288  0.891  1.0
  Se  Se29  1  0.932  0.212  0.391  1.0
  Se  Se30  1  0.305  0.971  0.071  1.0
  Se  Se31  1  0.068  0.788  0.391  1.0
[/CIF]
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The material described by K2MnSnSe4 crystallizes in the tetragonal P-4n2 space group. There are three inequivalent K sites. In the first K site, K(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. In the second K site, K(2) is bonded in a distorted square co-planar geometry to four equivalent Se(2) atoms. In the third K site, K(3) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to four equivalent Se(1) atoms to form distorted MnSe4 trigonal pyramids that share corners with four equivalent Sn(1)Se4 tetrahedra. In the second Mn site, Mn(2) is bonded to four equivalent Se(2) atoms to form distorted MnSe4 tetrahedra that share edges with two equivalent Sn(1)Se4 tetrahedra. Sn(1) is bonded to two equivalent Se(1) and two equivalent Se(2) atoms to form SnSe4 tetrahedra that share corners with two equivalent Mn(1)Se4 trigonal pyramids and  an edgeedge with one Mn(2)Se4 tetrahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to one K(3), two equivalent K(1), one Mn(1), and one Sn(1) atom. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to one K(2), one K(3), two equivalent K(1), one Mn(2), and one Sn(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K2MnSnSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.658
_cell_length_b   10.658
_cell_length_c   8.356
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   949.227
_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  0.253  0.753  0.750  1.0
  K  K1  1  0.500  0.500  0.500  1.0
  K  K2  1  0.000  0.000  0.000  1.0
  K  K3  1  0.747  0.247  0.750  1.0
  K  K4  1  0.000  0.500  0.250  1.0
  K  K5  1  0.500  0.000  0.750  1.0
  K  K6  1  0.247  0.253  0.250  1.0
  K  K7  1  0.753  0.747  0.250  1.0
  Mn  Mn8  1  0.500  0.500  0.000  1.0
  Mn  Mn9  1  0.000  0.000  0.500  1.0
  Mn  Mn10  1  0.000  0.500  0.750  1.0
  Mn  Mn11  1  0.500  0.000  0.250  1.0
  Sn  Sn12  1  0.279  0.779  0.250  1.0
  Sn  Sn13  1  0.721  0.221  0.250  1.0
  Sn  Sn14  1  0.221  0.279  0.750  1.0
  Sn  Sn15  1  0.779  0.721  0.750  1.0
  Se  Se16  1  0.288  0.568  0.109  1.0
  Se  Se17  1  0.971  0.695  0.929  1.0
  Se  Se18  1  0.471  0.805  0.429  1.0
  Se  Se19  1  0.712  0.432  0.109  1.0
  Se  Se20  1  0.029  0.305  0.929  1.0
  Se  Se21  1  0.695  0.029  0.071  1.0
  Se  Se22  1  0.529  0.195  0.429  1.0
  Se  Se23  1  0.805  0.529  0.571  1.0
  Se  Se24  1  0.212  0.068  0.609  1.0
  Se  Se25  1  0.788  0.932  0.609  1.0
  Se  Se26  1  0.195  0.471  0.571  1.0
  Se  Se27  1  0.568  0.712  0.891  1.0
  Se  Se28  1  0.432  0.288  0.891  1.0
  Se  Se29  1  0.932  0.212  0.391  1.0
  Se  Se30  1  0.305  0.971  0.071  1.0
  Se  Se31  1  0.068  0.788  0.391  1.0
[/CIF]
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