The material structure described by SnPSe3 crystallizes in the monoclinic Pc space group. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded to one Se(1), one Se(2), one Se(4), one Se(5), and one Se(6) atom to form distorted SnSe5 square pyramids that share  a cornercorner with one P(2)PSe3 tetrahedra, corners with two equivalent P(1)PSe3 tetrahedra, and  an edgeedge with one P(2)PSe3 tetrahedra. In the second Sn site, Sn(2) is bonded in a 5-coordinate geometry to one Se(2), one Se(3), one Se(4), one Se(5), and one Se(6) atom. There are two inequivalent P sites. In the first P site, P(1) is bonded to one P(2), one Se(3), one Se(4), and one Se(5) atom to form distorted PPSe3 tetrahedra that share corners with two equivalent Sn(1)Se5 square pyramids. In the second P site, P(2) is bonded to one P(1), one Se(1), one Se(2), and one Se(6) atom to form distorted PPSe3 tetrahedra that share  a cornercorner with one Sn(1)Se5 square pyramid and  an edgeedge with one Sn(1)Se5 square pyramid. There are six inequivalent Se sites. In the first Se site, Se(1) is bonded in an L-shaped geometry to one Sn(1) and one P(2) atom. In the second Se site, Se(2) is bonded in a 3-coordinate geometry to one Sn(1), one Sn(2), and one P(2) atom. In the third Se site, Se(3) is bonded in an L-shaped geometry to one Sn(2) and one P(1) atom. In the fourth Se site, Se(4) is bonded in a 3-coordinate geometry to one Sn(1), one Sn(2), and one P(1) atom. In the fifth Se site, Se(5) is bonded in a 3-coordinate geometry to one Sn(1), one Sn(2), and one P(1) atom. In the sixth Se site, Se(6) is bonded in a 3-coordinate geometry to one Sn(1), one Sn(2), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_SnPSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.879
_cell_length_b   6.920
_cell_length_c   12.236
_cell_angle_alpha   55.614
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   550.523
_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
  Sn  Sn0  1  0.891  0.797  0.208  1.0
  Sn  Sn1  1  0.364  0.259  0.196  1.0
  Sn  Sn2  1  0.109  0.797  0.708  1.0
  Sn  Sn3  1  0.636  0.259  0.696  1.0
  P  P4  1  0.641  0.877  0.568  1.0
  P  P5  1  0.359  0.877  0.068  1.0
  P  P6  1  0.149  0.122  0.939  1.0
  P  P7  1  0.851  0.122  0.439  1.0
  Se  Se8  1  0.944  0.895  0.955  1.0
  Se  Se9  1  0.751  0.364  0.241  1.0
  Se  Se10  1  0.452  0.703  0.975  1.0
  Se  Se11  1  0.243  0.634  0.262  1.0
  Se  Se12  1  0.056  0.895  0.455  1.0
  Se  Se13  1  0.553  0.112  0.058  1.0
  Se  Se14  1  0.062  0.281  0.044  1.0
  Se  Se15  1  0.249  0.364  0.741  1.0
  Se  Se16  1  0.938  0.281  0.544  1.0
  Se  Se17  1  0.548  0.703  0.475  1.0
  Se  Se18  1  0.447  0.112  0.558  1.0
  Se  Se19  1  0.757  0.634  0.762  1.0
[/CIF]
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The material structure described by SnPSe3 crystallizes in the monoclinic Pc space group. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded to one Se(1), one Se(2), one Se(4), one Se(5), and one Se(6) atom to form distorted SnSe5 square pyramids that share  a cornercorner with one P(2)PSe3 tetrahedra, corners with two equivalent P(1)PSe3 tetrahedra, and  an edgeedge with one P(2)PSe3 tetrahedra. In the second Sn site, Sn(2) is bonded in a 5-coordinate geometry to one Se(2), one Se(3), one Se(4), one Se(5), and one Se(6) atom. There are two inequivalent P sites. In the first P site, P(1) is bonded to one P(2), one Se(3), one Se(4), and one Se(5) atom to form distorted PPSe3 tetrahedra that share corners with two equivalent Sn(1)Se5 square pyramids. In the second P site, P(2) is bonded to one P(1), one Se(1), one Se(2), and one Se(6) atom to form distorted PPSe3 tetrahedra that share  a cornercorner with one Sn(1)Se5 square pyramid and  an edgeedge with one Sn(1)Se5 square pyramid. There are six inequivalent Se sites. In the first Se site, Se(1) is bonded in an L-shaped geometry to one Sn(1) and one P(2) atom. In the second Se site, Se(2) is bonded in a 3-coordinate geometry to one Sn(1), one Sn(2), and one P(2) atom. In the third Se site, Se(3) is bonded in an L-shaped geometry to one Sn(2) and one P(1) atom. In the fourth Se site, Se(4) is bonded in a 3-coordinate geometry to one Sn(1), one Sn(2), and one P(1) atom. In the fifth Se site, Se(5) is bonded in a 3-coordinate geometry to one Sn(1), one Sn(2), and one P(1) atom. In the sixth Se site, Se(6) is bonded in a 3-coordinate geometry to one Sn(1), one Sn(2), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_SnPSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.879
_cell_length_b   6.920
_cell_length_c   12.236
_cell_angle_alpha   55.614
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   550.523
_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
  Sn  Sn0  1  0.891  0.797  0.208  1.0
  Sn  Sn1  1  0.364  0.259  0.196  1.0
  Sn  Sn2  1  0.109  0.797  0.708  1.0
  Sn  Sn3  1  0.636  0.259  0.696  1.0
  P  P4  1  0.641  0.877  0.568  1.0
  P  P5  1  0.359  0.877  0.068  1.0
  P  P6  1  0.149  0.122  0.939  1.0
  P  P7  1  0.851  0.122  0.439  1.0
  Se  Se8  1  0.944  0.895  0.955  1.0
  Se  Se9  1  0.751  0.364  0.241  1.0
  Se  Se10  1  0.452  0.703  0.975  1.0
  Se  Se11  1  0.243  0.634  0.262  1.0
  Se  Se12  1  0.056  0.895  0.455  1.0
  Se  Se13  1  0.553  0.112  0.058  1.0
  Se  Se14  1  0.062  0.281  0.044  1.0
  Se  Se15  1  0.249  0.364  0.741  1.0
  Se  Se16  1  0.938  0.281  0.544  1.0
  Se  Se17  1  0.548  0.703  0.475  1.0
  Se  Se18  1  0.447  0.112  0.558  1.0
  Se  Se19  1  0.757  0.634  0.762  1.0
[/CIF]
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