The material described by Sr2TiP2O9 crystallizes in the monoclinic Cc space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 11-coordinate geometry to one O(1), one O(2), one O(3), two equivalent O(4), two equivalent O(5), two equivalent O(8), and two equivalent O(9) atoms. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(6), one O(7), one O(8), and one O(9) atom. Ti(1) is bonded to one O(2), one O(3), one O(6), one O(7), and two equivalent O(1) atoms to form TiO6 octahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 43°. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form PO4 tetrahedra that share corners with two equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-51°. In the second P site, P(2) is bonded to one O(6), one O(7), one O(8), and one O(9) atom to form PO4 tetrahedra that share corners with two equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 37-44°. There are nine inequivalent O sites. In the first O site, O(8) is bonded in a distorted single-bond geometry to one Sr(2), two equivalent Sr(1), and one P(2) atom. In the second O site, O(9) is bonded in a distorted single-bond geometry to one Sr(2), two equivalent Sr(1), and one P(2) atom. In the third O site, O(1) is bonded in a 3-coordinate geometry to one Sr(1) and two equivalent Ti(1) atoms. In the fourth O site, O(2) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(2), one Ti(1), and one P(1) atom. In the fifth O site, O(3) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(2), one Ti(1), and one P(1) atom. In the sixth O site, O(4) is bonded in a distorted single-bond geometry to one Sr(2), two equivalent Sr(1), and one P(1) atom. In the seventh O site, O(5) is bonded in a distorted single-bond geometry to one Sr(2), two equivalent Sr(1), and one P(1) atom. In the eighth O site, O(6) is bonded in a 3-coordinate geometry to one Sr(2), one Ti(1), and one P(2) atom. In the ninth O site, O(7) is bonded in a 3-coordinate geometry to one Sr(2), one Ti(1), and one P(2) atom. is represented by the CIF card [CIF]
data_Sr2TiP2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.854
_cell_length_b   7.130
_cell_length_c   8.828
_cell_angle_alpha   76.396
_cell_angle_beta   77.716
_cell_angle_gamma   115.747
_symmetry_Int_Tables_number   1
_cell_volume   352.419
_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
  Sr  Sr0  1  0.207  0.956  0.086  1.0
  Sr  Sr1  1  0.793  0.043  0.914  1.0
  Sr  Sr2  1  0.627  0.377  0.248  1.0
  Sr  Sr3  1  0.375  0.625  0.752  1.0
  Ti  Ti4  1  0.002  0.984  0.494  1.0
  Ti  Ti5  1  0.996  0.478  0.506  1.0
  P  P6  1  0.827  0.577  0.846  1.0
  P  P7  1  0.173  0.422  0.154  1.0
  P  P8  1  0.587  0.837  0.326  1.0
  P  P9  1  0.413  0.163  0.674  1.0
  O  O10  1  0.043  0.796  0.413  1.0
  O  O11  1  0.956  0.209  0.587  1.0
  O  O12  1  0.020  0.483  0.273  1.0
  O  O13  1  0.209  0.245  0.271  1.0
  O  O14  1  0.980  0.516  0.729  1.0
  O  O15  1  0.793  0.755  0.727  1.0
  O  O16  1  0.402  0.640  0.048  1.0
  O  O17  1  0.050  0.312  0.047  1.0
  O  O18  1  0.598  0.359  0.953  1.0
  O  O19  1  0.949  0.688  0.952  1.0
  O  O20  1  0.348  0.622  0.446  1.0
  O  O21  1  0.708  0.932  0.446  1.0
  O  O22  1  0.653  0.378  0.554  1.0
  O  O23  1  0.294  0.067  0.554  1.0
  O  O24  1  0.743  0.782  0.214  1.0
  O  O25  1  0.542  0.004  0.215  1.0
  O  O26  1  0.257  0.218  0.785  1.0
  O  O27  1  0.458  0.996  0.786  1.0
[/CIF]
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The material described by Sr2TiP2O9 crystallizes in the monoclinic Cc space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 11-coordinate geometry to one O(1), one O(2), one O(3), two equivalent O(4), two equivalent O(5), two equivalent O(8), and two equivalent O(9) atoms. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(6), one O(7), one O(8), and one O(9) atom. Ti(1) is bonded to one O(2), one O(3), one O(6), one O(7), and two equivalent O(1) atoms to form TiO6 octahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 43°. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form PO4 tetrahedra that share corners with two equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-51°. In the second P site, P(2) is bonded to one O(6), one O(7), one O(8), and one O(9) atom to form PO4 tetrahedra that share corners with two equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 37-44°. There are nine inequivalent O sites. In the first O site, O(8) is bonded in a distorted single-bond geometry to one Sr(2), two equivalent Sr(1), and one P(2) atom. In the second O site, O(9) is bonded in a distorted single-bond geometry to one Sr(2), two equivalent Sr(1), and one P(2) atom. In the third O site, O(1) is bonded in a 3-coordinate geometry to one Sr(1) and two equivalent Ti(1) atoms. In the fourth O site, O(2) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(2), one Ti(1), and one P(1) atom. In the fifth O site, O(3) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(2), one Ti(1), and one P(1) atom. In the sixth O site, O(4) is bonded in a distorted single-bond geometry to one Sr(2), two equivalent Sr(1), and one P(1) atom. In the seventh O site, O(5) is bonded in a distorted single-bond geometry to one Sr(2), two equivalent Sr(1), and one P(1) atom. In the eighth O site, O(6) is bonded in a 3-coordinate geometry to one Sr(2), one Ti(1), and one P(2) atom. In the ninth O site, O(7) is bonded in a 3-coordinate geometry to one Sr(2), one Ti(1), and one P(2) atom. is represented by the CIF card [CIF]
data_Sr2TiP2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.854
_cell_length_b   7.130
_cell_length_c   8.828
_cell_angle_alpha   76.396
_cell_angle_beta   77.716
_cell_angle_gamma   115.747
_symmetry_Int_Tables_number   1
_cell_volume   352.419
_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
  Sr  Sr0  1  0.207  0.956  0.086  1.0
  Sr  Sr1  1  0.793  0.043  0.914  1.0
  Sr  Sr2  1  0.627  0.377  0.248  1.0
  Sr  Sr3  1  0.375  0.625  0.752  1.0
  Ti  Ti4  1  0.002  0.984  0.494  1.0
  Ti  Ti5  1  0.996  0.478  0.506  1.0
  P  P6  1  0.827  0.577  0.846  1.0
  P  P7  1  0.173  0.422  0.154  1.0
  P  P8  1  0.587  0.837  0.326  1.0
  P  P9  1  0.413  0.163  0.674  1.0
  O  O10  1  0.043  0.796  0.413  1.0
  O  O11  1  0.956  0.209  0.587  1.0
  O  O12  1  0.020  0.483  0.273  1.0
  O  O13  1  0.209  0.245  0.271  1.0
  O  O14  1  0.980  0.516  0.729  1.0
  O  O15  1  0.793  0.755  0.727  1.0
  O  O16  1  0.402  0.640  0.048  1.0
  O  O17  1  0.050  0.312  0.047  1.0
  O  O18  1  0.598  0.359  0.953  1.0
  O  O19  1  0.949  0.688  0.952  1.0
  O  O20  1  0.348  0.622  0.446  1.0
  O  O21  1  0.708  0.932  0.446  1.0
  O  O22  1  0.653  0.378  0.554  1.0
  O  O23  1  0.294  0.067  0.554  1.0
  O  O24  1  0.743  0.782  0.214  1.0
  O  O25  1  0.542  0.004  0.215  1.0
  O  O26  1  0.257  0.218  0.785  1.0
  O  O27  1  0.458  0.996  0.786  1.0
[/CIF]
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