The crystal structure described by CaSnP2O7 crystallizes in the triclinic P-1 space group. Ca(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(7), and two equivalent O(4) atoms to form CaO7 pentagonal bipyramids that share  a cornercorner with one Sn(1)O5 square pyramid, corners with three equivalent P(1)O4 tetrahedra, corners with four equivalent P(2)O4 tetrahedra,  an edgeedge with one Ca(1)O7 pentagonal bipyramid, and edges with two equivalent Sn(1)O5 square pyramids. Sn(1) is bonded to one O(1), one O(2), one O(3), one O(5), and one O(7) atom to form distorted SnO5 square pyramids that share  a cornercorner with one Ca(1)O7 pentagonal bipyramid, corners with two equivalent P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, and edges with two equivalent Ca(1)O7 pentagonal bipyramids. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Ca(1)O7 pentagonal bipyramids, corners with three equivalent Sn(1)O5 square pyramids, and  a cornercorner with one P(2)O4 tetrahedra. In the second P site, P(2) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share corners with four equivalent Ca(1)O7 pentagonal bipyramids, corners with two equivalent Sn(1)O5 square pyramids, and  a cornercorner with one P(1)O4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Ca(1), one Sn(1), and one P(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ca(1), one Sn(1), and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ca(1), one Sn(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Ca(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Ca(1), one Sn(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Ca(1), one Sn(1), and one P(2) atom. is represented by the CIF file [CIF]
data_CaSnP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.561
_cell_length_b   7.030
_cell_length_c   7.058
_cell_angle_alpha   86.484
_cell_angle_beta   88.302
_cell_angle_gamma   67.356
_symmetry_Int_Tables_number   1
_cell_volume   299.912
_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
  Ca  Ca0  1  0.312  0.705  0.633  1.0
  Ca  Ca1  1  0.688  0.295  0.367  1.0
  Sn  Sn2  1  0.262  0.116  0.150  1.0
  Sn  Sn3  1  0.738  0.884  0.850  1.0
  P  P4  1  0.183  0.660  0.147  1.0
  P  P5  1  0.817  0.340  0.853  1.0
  P  P6  1  0.222  0.233  0.604  1.0
  P  P7  1  0.778  0.767  0.396  1.0
  O  O8  1  0.125  0.738  0.938  1.0
  O  O9  1  0.875  0.262  0.062  1.0
  O  O10  1  0.229  0.815  0.266  1.0
  O  O11  1  0.771  0.185  0.734  1.0
  O  O12  1  0.358  0.442  0.167  1.0
  O  O13  1  0.642  0.558  0.833  1.0
  O  O14  1  0.647  0.631  0.436  1.0
  O  O15  1  0.353  0.369  0.564  1.0
  O  O16  1  0.091  0.217  0.428  1.0
  O  O17  1  0.909  0.783  0.572  1.0
  O  O18  1  0.044  0.353  0.763  1.0
  O  O19  1  0.641  0.986  0.315  1.0
  O  O20  1  0.359  0.014  0.685  1.0
  O  O21  1  0.956  0.647  0.237  1.0
[/CIF]
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The crystal structure described by CaSnP2O7 crystallizes in the triclinic P-1 space group. Ca(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(7), and two equivalent O(4) atoms to form CaO7 pentagonal bipyramids that share  a cornercorner with one Sn(1)O5 square pyramid, corners with three equivalent P(1)O4 tetrahedra, corners with four equivalent P(2)O4 tetrahedra,  an edgeedge with one Ca(1)O7 pentagonal bipyramid, and edges with two equivalent Sn(1)O5 square pyramids. Sn(1) is bonded to one O(1), one O(2), one O(3), one O(5), and one O(7) atom to form distorted SnO5 square pyramids that share  a cornercorner with one Ca(1)O7 pentagonal bipyramid, corners with two equivalent P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, and edges with two equivalent Ca(1)O7 pentagonal bipyramids. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Ca(1)O7 pentagonal bipyramids, corners with three equivalent Sn(1)O5 square pyramids, and  a cornercorner with one P(2)O4 tetrahedra. In the second P site, P(2) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share corners with four equivalent Ca(1)O7 pentagonal bipyramids, corners with two equivalent Sn(1)O5 square pyramids, and  a cornercorner with one P(1)O4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Ca(1), one Sn(1), and one P(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ca(1), one Sn(1), and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ca(1), one Sn(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Ca(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Ca(1), one Sn(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Ca(1), one Sn(1), and one P(2) atom. is represented by the CIF file [CIF]
data_CaSnP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.561
_cell_length_b   7.030
_cell_length_c   7.058
_cell_angle_alpha   86.484
_cell_angle_beta   88.302
_cell_angle_gamma   67.356
_symmetry_Int_Tables_number   1
_cell_volume   299.912
_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
  Ca  Ca0  1  0.312  0.705  0.633  1.0
  Ca  Ca1  1  0.688  0.295  0.367  1.0
  Sn  Sn2  1  0.262  0.116  0.150  1.0
  Sn  Sn3  1  0.738  0.884  0.850  1.0
  P  P4  1  0.183  0.660  0.147  1.0
  P  P5  1  0.817  0.340  0.853  1.0
  P  P6  1  0.222  0.233  0.604  1.0
  P  P7  1  0.778  0.767  0.396  1.0
  O  O8  1  0.125  0.738  0.938  1.0
  O  O9  1  0.875  0.262  0.062  1.0
  O  O10  1  0.229  0.815  0.266  1.0
  O  O11  1  0.771  0.185  0.734  1.0
  O  O12  1  0.358  0.442  0.167  1.0
  O  O13  1  0.642  0.558  0.833  1.0
  O  O14  1  0.647  0.631  0.436  1.0
  O  O15  1  0.353  0.369  0.564  1.0
  O  O16  1  0.091  0.217  0.428  1.0
  O  O17  1  0.909  0.783  0.572  1.0
  O  O18  1  0.044  0.353  0.763  1.0
  O  O19  1  0.641  0.986  0.315  1.0
  O  O20  1  0.359  0.014  0.685  1.0
  O  O21  1  0.956  0.647  0.237  1.0
[/CIF]
.