The structure described by Sn2P2O7 crystallizes in the triclinic P-1 space group. There are four inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 4-coordinate geometry to one O(1), one O(12), one O(3), and one O(9) atom. In the second Sn site, Sn(2) is bonded to one O(13), one O(4), one O(6), one O(7), and one O(8) atom to form SnO5 square pyramids that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, and corners with three equivalent P(3)O4 tetrahedra. In the third Sn site, Sn(3) is bonded in a 5-coordinate geometry to one O(1), one O(12), one O(14), one O(6), and one O(9) atom. In the fourth Sn site, Sn(4) is bonded in a 4-coordinate geometry to one O(2), one O(8), and two equivalent O(11) atoms. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(10), one O(3), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Sn(2)O5 square pyramid and  a cornercorner with one P(4)O4 tetrahedra. In the second P site, P(2) is bonded to one O(11), one O(2), one O(5), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Sn(2)O5 square pyramid and  a cornercorner with one P(3)O4 tetrahedra. In the third P site, P(3) is bonded to one O(13), one O(4), one O(5), and one O(8) atom to form PO4 tetrahedra that share corners with three equivalent Sn(2)O5 square pyramids and  a cornercorner with one P(2)O4 tetrahedra. In the fourth P site, P(4) is bonded to one O(10), one O(12), one O(14), and one O(9) atom to form corner-sharing PO4 tetrahedra. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Sn(1), one Sn(3), and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Sn(4) and one P(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Sn(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Sn(2) and one P(3) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one P(2) and one P(3) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Sn(2), one Sn(3), and one P(1) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one Sn(2) and one P(2) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Sn(2), one Sn(4), and one P(3) atom. In the ninth O site, O(9) is bonded in a 1-coordinate geometry to one Sn(1), one Sn(3), and one P(4) atom. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to one P(1) and one P(4) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to two equivalent Sn(4) and one P(2) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Sn(1), one Sn(3), and one P(4) atom. In the thirteenth O site, O(13) is bonded in a distorted single-bond geometry to one Sn(2) and one P(3) atom. In the fourteenth O site, O(14) is bonded in a single-bond geometry to one Sn(3) and one P(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sn2P2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.986
_cell_length_b   7.044
_cell_length_c   13.018
_cell_angle_alpha   83.333
_cell_angle_beta   89.970
_cell_angle_gamma   89.993
_symmetry_Int_Tables_number   1
_cell_volume   636.262
_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  0.910  0.209  0.864  1.0
  Sn  Sn1  1  0.745  0.821  0.650  1.0
  Sn  Sn2  1  0.667  0.197  0.138  1.0
  Sn  Sn3  1  0.661  0.619  0.377  1.0
  Sn  Sn4  1  0.339  0.381  0.623  1.0
  Sn  Sn5  1  0.333  0.803  0.862  1.0
  Sn  Sn6  1  0.255  0.179  0.350  1.0
  Sn  Sn7  1  0.090  0.791  0.136  1.0
  P  P8  1  0.833  0.697  0.915  1.0
  P  P9  1  0.816  0.299  0.588  1.0
  P  P10  1  0.768  0.099  0.400  1.0
  P  P11  1  0.576  0.708  0.100  1.0
  P  P12  1  0.424  0.292  0.900  1.0
  P  P13  1  0.232  0.901  0.600  1.0
  P  P14  1  0.184  0.701  0.412  1.0
  P  P15  1  0.167  0.303  0.085  1.0
  O  O16  1  0.998  0.813  0.959  1.0
  O  O17  1  0.992  0.367  0.641  1.0
  O  O18  1  0.912  0.527  0.866  1.0
  O  O19  1  0.913  0.078  0.315  1.0
  O  O20  1  0.889  0.210  0.485  1.0
  O  O21  1  0.699  0.829  0.845  1.0
  O  O22  1  0.701  0.142  0.654  1.0
  O  O23  1  0.701  0.908  0.461  1.0
  O  O24  1  0.704  0.864  0.139  1.0
  O  O25  1  0.705  0.609  0.014  1.0
  O  O26  1  0.678  0.466  0.548  1.0
  O  O27  1  0.603  0.204  0.959  1.0
  O  O28  1  0.599  0.230  0.362  1.0
  O  O29  1  0.530  0.543  0.181  1.0
  O  O30  1  0.470  0.457  0.819  1.0
  O  O31  1  0.401  0.770  0.638  1.0
  O  O32  1  0.397  0.796  0.041  1.0
  O  O33  1  0.322  0.534  0.452  1.0
  O  O34  1  0.295  0.391  0.986  1.0
  O  O35  1  0.296  0.136  0.861  1.0
  O  O36  1  0.299  0.092  0.539  1.0
  O  O37  1  0.299  0.858  0.346  1.0
  O  O38  1  0.301  0.171  0.155  1.0
  O  O39  1  0.111  0.790  0.515  1.0
  O  O40  1  0.087  0.922  0.685  1.0
  O  O41  1  0.088  0.473  0.134  1.0
  O  O42  1  0.008  0.632  0.359  1.0
  O  O43  1  0.002  0.187  0.041  1.0
[/CIF]
.
The structure described by Sn2P2O7 crystallizes in the triclinic P-1 space group. There are four inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 4-coordinate geometry to one O(1), one O(12), one O(3), and one O(9) atom. In the second Sn site, Sn(2) is bonded to one O(13), one O(4), one O(6), one O(7), and one O(8) atom to form SnO5 square pyramids that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, and corners with three equivalent P(3)O4 tetrahedra. In the third Sn site, Sn(3) is bonded in a 5-coordinate geometry to one O(1), one O(12), one O(14), one O(6), and one O(9) atom. In the fourth Sn site, Sn(4) is bonded in a 4-coordinate geometry to one O(2), one O(8), and two equivalent O(11) atoms. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(10), one O(3), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Sn(2)O5 square pyramid and  a cornercorner with one P(4)O4 tetrahedra. In the second P site, P(2) is bonded to one O(11), one O(2), one O(5), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Sn(2)O5 square pyramid and  a cornercorner with one P(3)O4 tetrahedra. In the third P site, P(3) is bonded to one O(13), one O(4), one O(5), and one O(8) atom to form PO4 tetrahedra that share corners with three equivalent Sn(2)O5 square pyramids and  a cornercorner with one P(2)O4 tetrahedra. In the fourth P site, P(4) is bonded to one O(10), one O(12), one O(14), and one O(9) atom to form corner-sharing PO4 tetrahedra. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Sn(1), one Sn(3), and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Sn(4) and one P(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Sn(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Sn(2) and one P(3) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one P(2) and one P(3) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Sn(2), one Sn(3), and one P(1) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one Sn(2) and one P(2) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Sn(2), one Sn(4), and one P(3) atom. In the ninth O site, O(9) is bonded in a 1-coordinate geometry to one Sn(1), one Sn(3), and one P(4) atom. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to one P(1) and one P(4) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to two equivalent Sn(4) and one P(2) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Sn(1), one Sn(3), and one P(4) atom. In the thirteenth O site, O(13) is bonded in a distorted single-bond geometry to one Sn(2) and one P(3) atom. In the fourteenth O site, O(14) is bonded in a single-bond geometry to one Sn(3) and one P(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sn2P2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.986
_cell_length_b   7.044
_cell_length_c   13.018
_cell_angle_alpha   83.333
_cell_angle_beta   89.970
_cell_angle_gamma   89.993
_symmetry_Int_Tables_number   1
_cell_volume   636.262
_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  0.910  0.209  0.864  1.0
  Sn  Sn1  1  0.745  0.821  0.650  1.0
  Sn  Sn2  1  0.667  0.197  0.138  1.0
  Sn  Sn3  1  0.661  0.619  0.377  1.0
  Sn  Sn4  1  0.339  0.381  0.623  1.0
  Sn  Sn5  1  0.333  0.803  0.862  1.0
  Sn  Sn6  1  0.255  0.179  0.350  1.0
  Sn  Sn7  1  0.090  0.791  0.136  1.0
  P  P8  1  0.833  0.697  0.915  1.0
  P  P9  1  0.816  0.299  0.588  1.0
  P  P10  1  0.768  0.099  0.400  1.0
  P  P11  1  0.576  0.708  0.100  1.0
  P  P12  1  0.424  0.292  0.900  1.0
  P  P13  1  0.232  0.901  0.600  1.0
  P  P14  1  0.184  0.701  0.412  1.0
  P  P15  1  0.167  0.303  0.085  1.0
  O  O16  1  0.998  0.813  0.959  1.0
  O  O17  1  0.992  0.367  0.641  1.0
  O  O18  1  0.912  0.527  0.866  1.0
  O  O19  1  0.913  0.078  0.315  1.0
  O  O20  1  0.889  0.210  0.485  1.0
  O  O21  1  0.699  0.829  0.845  1.0
  O  O22  1  0.701  0.142  0.654  1.0
  O  O23  1  0.701  0.908  0.461  1.0
  O  O24  1  0.704  0.864  0.139  1.0
  O  O25  1  0.705  0.609  0.014  1.0
  O  O26  1  0.678  0.466  0.548  1.0
  O  O27  1  0.603  0.204  0.959  1.0
  O  O28  1  0.599  0.230  0.362  1.0
  O  O29  1  0.530  0.543  0.181  1.0
  O  O30  1  0.470  0.457  0.819  1.0
  O  O31  1  0.401  0.770  0.638  1.0
  O  O32  1  0.397  0.796  0.041  1.0
  O  O33  1  0.322  0.534  0.452  1.0
  O  O34  1  0.295  0.391  0.986  1.0
  O  O35  1  0.296  0.136  0.861  1.0
  O  O36  1  0.299  0.092  0.539  1.0
  O  O37  1  0.299  0.858  0.346  1.0
  O  O38  1  0.301  0.171  0.155  1.0
  O  O39  1  0.111  0.790  0.515  1.0
  O  O40  1  0.087  0.922  0.685  1.0
  O  O41  1  0.088  0.473  0.134  1.0
  O  O42  1  0.008  0.632  0.359  1.0
  O  O43  1  0.002  0.187  0.041  1.0
[/CIF]
.