The material described by Sr2P7I crystallizes in the cubic P2_13 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 13-coordinate geometry to six equivalent P(2), six equivalent P(3), and one I(1) atom. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one P(1), three equivalent P(2), and three equivalent I(1) atoms. There are three inequivalent P sites. In the first P site, P(1) is bonded to one Sr(2) and three equivalent P(2) atoms to form PSrP3 tetrahedra that share corners with three equivalent P(2)Sr3P2 square pyramids and corners with three equivalent I(1)Sr4 trigonal pyramids. In the second P site, P(2) is bonded to one Sr(2), two equivalent Sr(1), one P(1), and one P(3) atom to form distorted PSr3P2 square pyramids that share corners with six equivalent P(2)Sr3P2 square pyramids,  a cornercorner with one P(1)SrP3 tetrahedra, corners with three equivalent I(1)Sr4 trigonal pyramids, edges with four equivalent P(2)Sr3P2 square pyramids, and  an edgeedge with one I(1)Sr4 trigonal pyramid. In the third P site, P(3) is bonded in a 5-coordinate geometry to two equivalent Sr(1), one P(2), and two equivalent P(3) atoms. I(1) is bonded to one Sr(1) and three equivalent Sr(2) atoms to form ISr4 trigonal pyramids that share corners with nine equivalent P(2)Sr3P2 square pyramids, corners with three equivalent P(1)SrP3 tetrahedra, corners with six equivalent I(1)Sr4 trigonal pyramids, and edges with three equivalent P(2)Sr3P2 square pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr2P7I
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.037
_cell_length_b   10.037
_cell_length_c   10.037
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1010.993
_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
  Sr  Sr0  1  0.154  0.654  0.846  1.0
  Sr  Sr1  1  0.654  0.846  0.154  1.0
  Sr  Sr2  1  0.846  0.154  0.654  1.0
  Sr  Sr3  1  0.346  0.346  0.346  1.0
  Sr  Sr4  1  0.902  0.402  0.098  1.0
  Sr  Sr5  1  0.402  0.098  0.902  1.0
  Sr  Sr6  1  0.098  0.902  0.402  1.0
  Sr  Sr7  1  0.598  0.598  0.598  1.0
  P  P8  1  0.719  0.219  0.281  1.0
  P  P9  1  0.219  0.281  0.719  1.0
  P  P10  1  0.281  0.719  0.219  1.0
  P  P11  1  0.781  0.781  0.781  1.0
  P  P12  1  0.308  0.463  0.643  1.0
  P  P13  1  0.357  0.808  0.037  1.0
  P  P14  1  0.963  0.857  0.692  1.0
  P  P15  1  0.808  0.037  0.357  1.0
  P  P16  1  0.857  0.692  0.963  1.0
  P  P17  1  0.463  0.643  0.308  1.0
  P  P18  1  0.692  0.963  0.857  1.0
  P  P19  1  0.643  0.308  0.463  1.0
  P  P20  1  0.037  0.357  0.808  1.0
  P  P21  1  0.192  0.537  0.143  1.0
  P  P22  1  0.143  0.192  0.537  1.0
  P  P23  1  0.537  0.143  0.192  1.0
  P  P24  1  0.358  0.459  0.030  1.0
  P  P25  1  0.970  0.858  0.041  1.0
  P  P26  1  0.959  0.470  0.642  1.0
  P  P27  1  0.858  0.041  0.970  1.0
  P  P28  1  0.470  0.642  0.959  1.0
  P  P29  1  0.459  0.030  0.358  1.0
  P  P30  1  0.642  0.959  0.470  1.0
  P  P31  1  0.030  0.358  0.459  1.0
  P  P32  1  0.041  0.970  0.858  1.0
  P  P33  1  0.142  0.541  0.530  1.0
  P  P34  1  0.530  0.142  0.541  1.0
  P  P35  1  0.541  0.530  0.142  1.0
  I  I36  1  0.348  0.848  0.652  1.0
  I  I37  1  0.848  0.652  0.348  1.0
  I  I38  1  0.652  0.348  0.848  1.0
  I  I39  1  0.152  0.152  0.152  1.0
[/CIF]
.
The material described by Sr2P7I crystallizes in the cubic P2_13 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 13-coordinate geometry to six equivalent P(2), six equivalent P(3), and one I(1) atom. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one P(1), three equivalent P(2), and three equivalent I(1) atoms. There are three inequivalent P sites. In the first P site, P(1) is bonded to one Sr(2) and three equivalent P(2) atoms to form PSrP3 tetrahedra that share corners with three equivalent P(2)Sr3P2 square pyramids and corners with three equivalent I(1)Sr4 trigonal pyramids. In the second P site, P(2) is bonded to one Sr(2), two equivalent Sr(1), one P(1), and one P(3) atom to form distorted PSr3P2 square pyramids that share corners with six equivalent P(2)Sr3P2 square pyramids,  a cornercorner with one P(1)SrP3 tetrahedra, corners with three equivalent I(1)Sr4 trigonal pyramids, edges with four equivalent P(2)Sr3P2 square pyramids, and  an edgeedge with one I(1)Sr4 trigonal pyramid. In the third P site, P(3) is bonded in a 5-coordinate geometry to two equivalent Sr(1), one P(2), and two equivalent P(3) atoms. I(1) is bonded to one Sr(1) and three equivalent Sr(2) atoms to form ISr4 trigonal pyramids that share corners with nine equivalent P(2)Sr3P2 square pyramids, corners with three equivalent P(1)SrP3 tetrahedra, corners with six equivalent I(1)Sr4 trigonal pyramids, and edges with three equivalent P(2)Sr3P2 square pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr2P7I
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.037
_cell_length_b   10.037
_cell_length_c   10.037
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1010.993
_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
  Sr  Sr0  1  0.154  0.654  0.846  1.0
  Sr  Sr1  1  0.654  0.846  0.154  1.0
  Sr  Sr2  1  0.846  0.154  0.654  1.0
  Sr  Sr3  1  0.346  0.346  0.346  1.0
  Sr  Sr4  1  0.902  0.402  0.098  1.0
  Sr  Sr5  1  0.402  0.098  0.902  1.0
  Sr  Sr6  1  0.098  0.902  0.402  1.0
  Sr  Sr7  1  0.598  0.598  0.598  1.0
  P  P8  1  0.719  0.219  0.281  1.0
  P  P9  1  0.219  0.281  0.719  1.0
  P  P10  1  0.281  0.719  0.219  1.0
  P  P11  1  0.781  0.781  0.781  1.0
  P  P12  1  0.308  0.463  0.643  1.0
  P  P13  1  0.357  0.808  0.037  1.0
  P  P14  1  0.963  0.857  0.692  1.0
  P  P15  1  0.808  0.037  0.357  1.0
  P  P16  1  0.857  0.692  0.963  1.0
  P  P17  1  0.463  0.643  0.308  1.0
  P  P18  1  0.692  0.963  0.857  1.0
  P  P19  1  0.643  0.308  0.463  1.0
  P  P20  1  0.037  0.357  0.808  1.0
  P  P21  1  0.192  0.537  0.143  1.0
  P  P22  1  0.143  0.192  0.537  1.0
  P  P23  1  0.537  0.143  0.192  1.0
  P  P24  1  0.358  0.459  0.030  1.0
  P  P25  1  0.970  0.858  0.041  1.0
  P  P26  1  0.959  0.470  0.642  1.0
  P  P27  1  0.858  0.041  0.970  1.0
  P  P28  1  0.470  0.642  0.959  1.0
  P  P29  1  0.459  0.030  0.358  1.0
  P  P30  1  0.642  0.959  0.470  1.0
  P  P31  1  0.030  0.358  0.459  1.0
  P  P32  1  0.041  0.970  0.858  1.0
  P  P33  1  0.142  0.541  0.530  1.0
  P  P34  1  0.530  0.142  0.541  1.0
  P  P35  1  0.541  0.530  0.142  1.0
  I  I36  1  0.348  0.848  0.652  1.0
  I  I37  1  0.848  0.652  0.348  1.0
  I  I38  1  0.652  0.348  0.848  1.0
  I  I39  1  0.152  0.152  0.152  1.0
[/CIF]
.