The compound described by CaSnP2O7 crystallizes in the triclinic P-1 space group. Ca(1) is bonded to one O(2), one O(3), one O(4), one O(6), one O(7), and two equivalent O(5) atoms to form distorted CaO7 pentagonal bipyramids that share corners with two equivalent Sn(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, edges with two equivalent Sn(1)O6 octahedra,  an edgeedge with one Ca(1)O7 pentagonal bipyramid, and  an edgeedge with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 64-78°. Sn(1) is bonded to one O(2), one O(3), one O(4), one O(7), and two equivalent O(6) atoms to form distorted SnO6 octahedra that share corners with two equivalent Ca(1)O7 pentagonal bipyramids, corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra,  an edgeedge with one Sn(1)O6 octahedra, 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(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Sn(1)O6 octahedra, corners with two equivalent Ca(1)O7 pentagonal bipyramids,  a cornercorner with one P(2)O4 tetrahedra, and  an edgeedge with one Ca(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 44-69°. In the second P site, P(2) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Sn(1)O6 octahedra, corners with three equivalent Ca(1)O7 pentagonal bipyramids, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 61-66°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ca(1), one Sn(1), and one P(1) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Ca(1), one Sn(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ca(1), one Sn(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to two equivalent Ca(1) and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Ca(1), two equivalent Sn(1), and one P(1) atom. In the seventh O site, O(7) is bonded in a distorted single-bond 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   6.874
_cell_length_b   6.947
_cell_length_c   7.033
_cell_angle_alpha   85.811
_cell_angle_beta   65.119
_cell_angle_gamma   84.581
_symmetry_Int_Tables_number   1
_cell_volume   303.105
_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  0.730  0.138  0.837  1.0
  Ca  Ca1  1  0.270  0.862  0.163  1.0
  Sn  Sn2  1  0.888  0.336  0.254  1.0
  Sn  Sn3  1  0.112  0.664  0.746  1.0
  P  P4  1  0.764  0.847  0.259  1.0
  P  P5  1  0.236  0.153  0.741  1.0
  P  P6  1  0.354  0.349  0.306  1.0
  P  P7  1  0.646  0.651  0.694  1.0
  O  O8  1  0.376  0.271  0.526  1.0
  O  O9  1  0.624  0.729  0.474  1.0
  O  O10  1  0.874  0.006  0.312  1.0
  O  O11  1  0.126  0.994  0.688  1.0
  O  O12  1  0.746  0.443  0.656  1.0
  O  O13  1  0.254  0.557  0.344  1.0
  O  O14  1  0.415  0.668  0.862  1.0
  O  O15  1  0.585  0.332  0.138  1.0
  O  O16  1  0.392  0.085  0.837  1.0
  O  O17  1  0.608  0.915  0.163  1.0
  O  O18  1  0.046  0.292  0.883  1.0
  O  O19  1  0.954  0.708  0.117  1.0
  O  O20  1  0.790  0.790  0.726  1.0
  O  O21  1  0.210  0.210  0.274  1.0
[/CIF]
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The compound described by CaSnP2O7 crystallizes in the triclinic P-1 space group. Ca(1) is bonded to one O(2), one O(3), one O(4), one O(6), one O(7), and two equivalent O(5) atoms to form distorted CaO7 pentagonal bipyramids that share corners with two equivalent Sn(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, edges with two equivalent Sn(1)O6 octahedra,  an edgeedge with one Ca(1)O7 pentagonal bipyramid, and  an edgeedge with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 64-78°. Sn(1) is bonded to one O(2), one O(3), one O(4), one O(7), and two equivalent O(6) atoms to form distorted SnO6 octahedra that share corners with two equivalent Ca(1)O7 pentagonal bipyramids, corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra,  an edgeedge with one Sn(1)O6 octahedra, 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(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Sn(1)O6 octahedra, corners with two equivalent Ca(1)O7 pentagonal bipyramids,  a cornercorner with one P(2)O4 tetrahedra, and  an edgeedge with one Ca(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 44-69°. In the second P site, P(2) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Sn(1)O6 octahedra, corners with three equivalent Ca(1)O7 pentagonal bipyramids, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 61-66°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ca(1), one Sn(1), and one P(1) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Ca(1), one Sn(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ca(1), one Sn(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to two equivalent Ca(1) and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Ca(1), two equivalent Sn(1), and one P(1) atom. In the seventh O site, O(7) is bonded in a distorted single-bond 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   6.874
_cell_length_b   6.947
_cell_length_c   7.033
_cell_angle_alpha   85.811
_cell_angle_beta   65.119
_cell_angle_gamma   84.581
_symmetry_Int_Tables_number   1
_cell_volume   303.105
_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  0.730  0.138  0.837  1.0
  Ca  Ca1  1  0.270  0.862  0.163  1.0
  Sn  Sn2  1  0.888  0.336  0.254  1.0
  Sn  Sn3  1  0.112  0.664  0.746  1.0
  P  P4  1  0.764  0.847  0.259  1.0
  P  P5  1  0.236  0.153  0.741  1.0
  P  P6  1  0.354  0.349  0.306  1.0
  P  P7  1  0.646  0.651  0.694  1.0
  O  O8  1  0.376  0.271  0.526  1.0
  O  O9  1  0.624  0.729  0.474  1.0
  O  O10  1  0.874  0.006  0.312  1.0
  O  O11  1  0.126  0.994  0.688  1.0
  O  O12  1  0.746  0.443  0.656  1.0
  O  O13  1  0.254  0.557  0.344  1.0
  O  O14  1  0.415  0.668  0.862  1.0
  O  O15  1  0.585  0.332  0.138  1.0
  O  O16  1  0.392  0.085  0.837  1.0
  O  O17  1  0.608  0.915  0.163  1.0
  O  O18  1  0.046  0.292  0.883  1.0
  O  O19  1  0.954  0.708  0.117  1.0
  O  O20  1  0.790  0.790  0.726  1.0
  O  O21  1  0.210  0.210  0.274  1.0
[/CIF]
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