The crystal structure described by CaSnO2 crystallizes in the triclinic P-1 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted CaO6 pentagonal pyramids that share corners with four equivalent Ca(2)O5 trigonal bipyramids,  an edgeedge with one Ca(2)O5 trigonal bipyramid, and faces with two equivalent Ca(1)O6 pentagonal pyramids. In the second Ca site, Ca(2) is bonded to one O(3), two equivalent O(2), and two equivalent O(4) atoms to form distorted CaO5 trigonal bipyramids that share corners with four equivalent Ca(1)O6 pentagonal pyramids,  an edgeedge with one Ca(1)O6 pentagonal pyramid, and edges with two equivalent Ca(2)O5 trigonal bipyramids. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a T-shaped geometry to one O(1), one O(2), and one O(3) atom. In the second Sn site, Sn(2) is bonded in a 3-coordinate geometry to one O(1), one O(2), and one O(4) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Ca(1), one Sn(1), and one Sn(2) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to two equivalent Ca(2), one Sn(1), and one Sn(2) atom. In the third O site, O(3) is bonded to one Ca(2), two equivalent Ca(1), and one Sn(1) atom to form OCa3Sn tetrahedra that share corners with four equivalent O(4)Ca4Sn square pyramids, corners with two equivalent O(3)Ca3Sn tetrahedra, and  an edgeedge with one O(4)Ca4Sn square pyramid. In the fourth O site, O(4) is bonded to two equivalent Ca(1), two equivalent Ca(2), and one Sn(2) atom to form OCa4Sn square pyramids that share corners with four equivalent O(3)Ca3Sn tetrahedra, edges with two equivalent O(4)Ca4Sn square pyramids, and  an edgeedge with one O(3)Ca3Sn tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaSnO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.294
_cell_length_b   9.102
_cell_length_c   9.449
_cell_angle_alpha   78.727
_cell_angle_beta   80.418
_cell_angle_gamma   80.909
_symmetry_Int_Tables_number   1
_cell_volume   271.652
_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
  Ca  Ca0  1  0.994  0.933  0.236  1.0
  Ca  Ca1  1  0.006  0.067  0.764  1.0
  Ca  Ca2  1  0.149  0.237  0.400  1.0
  Ca  Ca3  1  0.851  0.763  0.600  1.0
  Sn  Sn4  1  0.389  0.688  0.949  1.0
  Sn  Sn5  1  0.662  0.612  0.326  1.0
  Sn  Sn6  1  0.338  0.388  0.674  1.0
  Sn  Sn7  1  0.611  0.312  0.051  1.0
  O  O8  1  0.394  0.229  0.868  1.0
  O  O9  1  0.381  0.600  0.723  1.0
  O  O10  1  0.619  0.400  0.277  1.0
  O  O11  1  0.606  0.771  0.132  1.0
  O  O12  1  0.569  0.877  0.806  1.0
  O  O13  1  0.400  0.836  0.424  1.0
  O  O14  1  0.431  0.123  0.194  1.0
  O  O15  1  0.600  0.164  0.576  1.0
[/CIF]
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The crystal structure described by CaSnO2 crystallizes in the triclinic P-1 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted CaO6 pentagonal pyramids that share corners with four equivalent Ca(2)O5 trigonal bipyramids,  an edgeedge with one Ca(2)O5 trigonal bipyramid, and faces with two equivalent Ca(1)O6 pentagonal pyramids. In the second Ca site, Ca(2) is bonded to one O(3), two equivalent O(2), and two equivalent O(4) atoms to form distorted CaO5 trigonal bipyramids that share corners with four equivalent Ca(1)O6 pentagonal pyramids,  an edgeedge with one Ca(1)O6 pentagonal pyramid, and edges with two equivalent Ca(2)O5 trigonal bipyramids. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a T-shaped geometry to one O(1), one O(2), and one O(3) atom. In the second Sn site, Sn(2) is bonded in a 3-coordinate geometry to one O(1), one O(2), and one O(4) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Ca(1), one Sn(1), and one Sn(2) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to two equivalent Ca(2), one Sn(1), and one Sn(2) atom. In the third O site, O(3) is bonded to one Ca(2), two equivalent Ca(1), and one Sn(1) atom to form OCa3Sn tetrahedra that share corners with four equivalent O(4)Ca4Sn square pyramids, corners with two equivalent O(3)Ca3Sn tetrahedra, and  an edgeedge with one O(4)Ca4Sn square pyramid. In the fourth O site, O(4) is bonded to two equivalent Ca(1), two equivalent Ca(2), and one Sn(2) atom to form OCa4Sn square pyramids that share corners with four equivalent O(3)Ca3Sn tetrahedra, edges with two equivalent O(4)Ca4Sn square pyramids, and  an edgeedge with one O(3)Ca3Sn tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaSnO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.294
_cell_length_b   9.102
_cell_length_c   9.449
_cell_angle_alpha   78.727
_cell_angle_beta   80.418
_cell_angle_gamma   80.909
_symmetry_Int_Tables_number   1
_cell_volume   271.652
_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
  Ca  Ca0  1  0.994  0.933  0.236  1.0
  Ca  Ca1  1  0.006  0.067  0.764  1.0
  Ca  Ca2  1  0.149  0.237  0.400  1.0
  Ca  Ca3  1  0.851  0.763  0.600  1.0
  Sn  Sn4  1  0.389  0.688  0.949  1.0
  Sn  Sn5  1  0.662  0.612  0.326  1.0
  Sn  Sn6  1  0.338  0.388  0.674  1.0
  Sn  Sn7  1  0.611  0.312  0.051  1.0
  O  O8  1  0.394  0.229  0.868  1.0
  O  O9  1  0.381  0.600  0.723  1.0
  O  O10  1  0.619  0.400  0.277  1.0
  O  O11  1  0.606  0.771  0.132  1.0
  O  O12  1  0.569  0.877  0.806  1.0
  O  O13  1  0.400  0.836  0.424  1.0
  O  O14  1  0.431  0.123  0.194  1.0
  O  O15  1  0.600  0.164  0.576  1.0
[/CIF]
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