The material structure described by Sr8MgP4(O4I)4 crystallizes in the triclinic P1 space group. There are eight inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(13), one O(15), one O(4), one O(5), and one I(4) atom. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one O(14), one O(16), one O(2), one O(3), one O(6), one O(7), one O(9), and one I(3) atom. In the third Sr site, Sr(3) is bonded in a 8-coordinate geometry to one O(12), one O(13), one O(15), one O(2), one O(3), one O(6), one O(7), and one I(1) atom. In the fourth Sr site, Sr(4) is bonded in a 6-coordinate geometry to one O(11), one O(14), one O(16), one O(4), one O(5), one O(8), and one I(2) atom. In the fifth Sr site, Sr(5) is bonded in a 8-coordinate geometry to one O(10), one O(11), one O(16), one O(2), one O(8), one I(2), one I(3), and one I(4) atom. In the sixth Sr site, Sr(6) is bonded in a 8-coordinate geometry to one O(1), one O(12), one O(15), one O(7), one O(9), one I(1), one I(3), and one I(4) atom. In the seventh Sr site, Sr(7) is bonded in a 8-coordinate geometry to one O(12), one O(14), one O(4), one O(6), one O(9), one I(1), one I(2), and one I(4) atom. In the eighth Sr site, Sr(8) is bonded in a 8-coordinate geometry to one Mg(1), one O(10), one O(11), one O(13), one O(3), one O(5), one I(1), and one I(2) atom. Mg(1) is bonded in a single-bond geometry to one Sr(8), one O(1), one I(1), and one I(3) atom. There are four inequivalent P sites. In the first P site, P(1) is bonded in a tetrahedral geometry to one O(1), one O(10), one O(16), and one O(7) atom. In the second P site, P(2) is bonded in a tetrahedral geometry to one O(15), one O(2), one O(8), and one O(9) atom. In the third P site, P(3) is bonded in a tetrahedral geometry to one O(12), one O(14), one O(3), and one O(5) atom. In the fourth P site, P(4) is bonded in a tetrahedral geometry to one O(11), one O(13), one O(4), and one O(6) atom. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(6), one Mg(1), and one P(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Sr(2), one Sr(3), one Sr(5), and one P(2) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to one Sr(2), one Sr(3), one Sr(8), and one P(3) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(4), one Sr(7), and one P(4) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one Sr(1), one Sr(4), one Sr(8), and one P(3) atom. In the sixth O site, O(6) is bonded in a 1-coordinate geometry to one Sr(2), one Sr(3), one Sr(7), and one P(4) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Sr(2), one Sr(3), one Sr(6), and one P(1) atom. In the eighth O site, O(8) is bonded in a 1-coordinate geometry to one Sr(4), one Sr(5), and one P(2) atom. In the ninth O site, O(9) is bonded in a distorted single-bond geometry to one Sr(2), one Sr(6), one Sr(7), and one P(2) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(5), one Sr(8), and one P(1) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Sr(4), one Sr(5), one Sr(8), and one P(4) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Sr(3), one Sr(6), one Sr(7), and one P(3) atom. In the thirteenth O site, O(13) is bonded in a distorted single-bond geometry to one Sr(1), one Sr(3), one Sr(8), and one P(4) atom. In the fourteenth O site, O(14) is bonded in a distorted single-bond geometry to one Sr(2), one Sr(4), one Sr(7), and one P(3) atom. In the fifteenth O site, O(15) is bonded in a distorted tetrahedral geometry to one Sr(1), one Sr(3), one Sr(6), and one P(2) atom. In the sixteenth O site, O(16) is bonded in a distorted single-bond geometry to one Sr(2), one Sr(4), one Sr(5), and one P(1) atom. There are four inequivalent I sites. In the first I site, I(1) is bonded in a 5-coordinate geometry to one Sr(3), one Sr(6), one Sr(7), one Sr(8), and one Mg(1) atom. In the second I site, I(2) is bonded in a 4-coordinate geometry to one Sr(4), one Sr(5), one Sr(7), and one Sr(8) atom. In the third I site, I(3) is bonded in a distorted see-saw-like geometry to one Sr(2), one Sr(5), one Sr(6), and one Mg(1) atom. In the fourth I site, I(4) is bonded in a distorted see-saw-like geometry to one Sr(1), one Sr(5), one Sr(6), and one Sr(7) atom. is represented by the CIF file [CIF]
data_Sr8MgP4(IO4)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.908
_cell_length_b   8.962
_cell_length_c   9.723
_cell_angle_alpha   89.579
_cell_angle_beta   115.820
_cell_angle_gamma   89.122
_symmetry_Int_Tables_number   1
_cell_volume   698.544
_cell_formula_units_Z   1
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  0.943  0.832  0.869  1.0
  Sr  Sr1  1  0.542  0.316  0.139  1.0
  Sr  Sr2  1  0.056  0.202  0.147  1.0
  Sr  Sr3  1  0.480  0.710  0.858  1.0
  Sr  Sr4  1  0.477  0.820  0.238  1.0
  Sr  Sr5  1  0.024  0.314  0.756  1.0
  Sr  Sr6  1  0.538  0.180  0.759  1.0
  Sr  Sr7  1  0.987  0.674  0.243  1.0
  Mg  Mg8  1  0.036  0.681  0.607  1.0
  P  P9  1  0.227  0.562  0.019  1.0
  P  P10  1  0.278  0.058  0.967  1.0
  P  P11  1  0.766  0.451  0.957  1.0
  P  P12  1  0.752  0.956  0.062  1.0
  I  I13  1  0.198  0.362  0.497  1.0
  I  I14  1  0.320  0.891  0.494  1.0
  I  I15  1  0.660  0.506  0.474  1.0
  I  I16  1  0.757  0.052  0.538  1.0
  O  O17  1  0.120  0.588  0.841  1.0
  O  O18  1  0.370  0.086  0.143  1.0
  O  O19  1  0.859  0.428  0.134  1.0
  O  O20  1  0.666  0.934  0.883  1.0
  O  O21  1  0.787  0.615  0.918  1.0
  O  O22  1  0.719  0.117  0.095  1.0
  O  O23  1  0.207  0.398  0.058  1.0
  O  O24  1  0.311  0.895  0.936  1.0
  O  O25  1  0.331  0.176  0.880  1.0
  O  O26  1  0.170  0.679  0.106  1.0
  O  O27  1  0.693  0.830  0.137  1.0
  O  O28  1  0.830  0.329  0.881  1.0
  O  O29  1  0.944  0.931  0.116  1.0
  O  O30  1  0.575  0.425  0.902  1.0
  O  O31  1  0.087  0.083  0.918  1.0
  O  O32  1  0.415  0.589  0.064  1.0
[/CIF]
.
The material structure described by Sr8MgP4(O4I)4 crystallizes in the triclinic P1 space group. There are eight inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(13), one O(15), one O(4), one O(5), and one I(4) atom. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one O(14), one O(16), one O(2), one O(3), one O(6), one O(7), one O(9), and one I(3) atom. In the third Sr site, Sr(3) is bonded in a 8-coordinate geometry to one O(12), one O(13), one O(15), one O(2), one O(3), one O(6), one O(7), and one I(1) atom. In the fourth Sr site, Sr(4) is bonded in a 6-coordinate geometry to one O(11), one O(14), one O(16), one O(4), one O(5), one O(8), and one I(2) atom. In the fifth Sr site, Sr(5) is bonded in a 8-coordinate geometry to one O(10), one O(11), one O(16), one O(2), one O(8), one I(2), one I(3), and one I(4) atom. In the sixth Sr site, Sr(6) is bonded in a 8-coordinate geometry to one O(1), one O(12), one O(15), one O(7), one O(9), one I(1), one I(3), and one I(4) atom. In the seventh Sr site, Sr(7) is bonded in a 8-coordinate geometry to one O(12), one O(14), one O(4), one O(6), one O(9), one I(1), one I(2), and one I(4) atom. In the eighth Sr site, Sr(8) is bonded in a 8-coordinate geometry to one Mg(1), one O(10), one O(11), one O(13), one O(3), one O(5), one I(1), and one I(2) atom. Mg(1) is bonded in a single-bond geometry to one Sr(8), one O(1), one I(1), and one I(3) atom. There are four inequivalent P sites. In the first P site, P(1) is bonded in a tetrahedral geometry to one O(1), one O(10), one O(16), and one O(7) atom. In the second P site, P(2) is bonded in a tetrahedral geometry to one O(15), one O(2), one O(8), and one O(9) atom. In the third P site, P(3) is bonded in a tetrahedral geometry to one O(12), one O(14), one O(3), and one O(5) atom. In the fourth P site, P(4) is bonded in a tetrahedral geometry to one O(11), one O(13), one O(4), and one O(6) atom. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(6), one Mg(1), and one P(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Sr(2), one Sr(3), one Sr(5), and one P(2) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to one Sr(2), one Sr(3), one Sr(8), and one P(3) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(4), one Sr(7), and one P(4) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one Sr(1), one Sr(4), one Sr(8), and one P(3) atom. In the sixth O site, O(6) is bonded in a 1-coordinate geometry to one Sr(2), one Sr(3), one Sr(7), and one P(4) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Sr(2), one Sr(3), one Sr(6), and one P(1) atom. In the eighth O site, O(8) is bonded in a 1-coordinate geometry to one Sr(4), one Sr(5), and one P(2) atom. In the ninth O site, O(9) is bonded in a distorted single-bond geometry to one Sr(2), one Sr(6), one Sr(7), and one P(2) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(5), one Sr(8), and one P(1) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Sr(4), one Sr(5), one Sr(8), and one P(4) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Sr(3), one Sr(6), one Sr(7), and one P(3) atom. In the thirteenth O site, O(13) is bonded in a distorted single-bond geometry to one Sr(1), one Sr(3), one Sr(8), and one P(4) atom. In the fourteenth O site, O(14) is bonded in a distorted single-bond geometry to one Sr(2), one Sr(4), one Sr(7), and one P(3) atom. In the fifteenth O site, O(15) is bonded in a distorted tetrahedral geometry to one Sr(1), one Sr(3), one Sr(6), and one P(2) atom. In the sixteenth O site, O(16) is bonded in a distorted single-bond geometry to one Sr(2), one Sr(4), one Sr(5), and one P(1) atom. There are four inequivalent I sites. In the first I site, I(1) is bonded in a 5-coordinate geometry to one Sr(3), one Sr(6), one Sr(7), one Sr(8), and one Mg(1) atom. In the second I site, I(2) is bonded in a 4-coordinate geometry to one Sr(4), one Sr(5), one Sr(7), and one Sr(8) atom. In the third I site, I(3) is bonded in a distorted see-saw-like geometry to one Sr(2), one Sr(5), one Sr(6), and one Mg(1) atom. In the fourth I site, I(4) is bonded in a distorted see-saw-like geometry to one Sr(1), one Sr(5), one Sr(6), and one Sr(7) atom. is represented by the CIF file [CIF]
data_Sr8MgP4(IO4)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.908
_cell_length_b   8.962
_cell_length_c   9.723
_cell_angle_alpha   89.579
_cell_angle_beta   115.820
_cell_angle_gamma   89.122
_symmetry_Int_Tables_number   1
_cell_volume   698.544
_cell_formula_units_Z   1
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  0.943  0.832  0.869  1.0
  Sr  Sr1  1  0.542  0.316  0.139  1.0
  Sr  Sr2  1  0.056  0.202  0.147  1.0
  Sr  Sr3  1  0.480  0.710  0.858  1.0
  Sr  Sr4  1  0.477  0.820  0.238  1.0
  Sr  Sr5  1  0.024  0.314  0.756  1.0
  Sr  Sr6  1  0.538  0.180  0.759  1.0
  Sr  Sr7  1  0.987  0.674  0.243  1.0
  Mg  Mg8  1  0.036  0.681  0.607  1.0
  P  P9  1  0.227  0.562  0.019  1.0
  P  P10  1  0.278  0.058  0.967  1.0
  P  P11  1  0.766  0.451  0.957  1.0
  P  P12  1  0.752  0.956  0.062  1.0
  I  I13  1  0.198  0.362  0.497  1.0
  I  I14  1  0.320  0.891  0.494  1.0
  I  I15  1  0.660  0.506  0.474  1.0
  I  I16  1  0.757  0.052  0.538  1.0
  O  O17  1  0.120  0.588  0.841  1.0
  O  O18  1  0.370  0.086  0.143  1.0
  O  O19  1  0.859  0.428  0.134  1.0
  O  O20  1  0.666  0.934  0.883  1.0
  O  O21  1  0.787  0.615  0.918  1.0
  O  O22  1  0.719  0.117  0.095  1.0
  O  O23  1  0.207  0.398  0.058  1.0
  O  O24  1  0.311  0.895  0.936  1.0
  O  O25  1  0.331  0.176  0.880  1.0
  O  O26  1  0.170  0.679  0.106  1.0
  O  O27  1  0.693  0.830  0.137  1.0
  O  O28  1  0.830  0.329  0.881  1.0
  O  O29  1  0.944  0.931  0.116  1.0
  O  O30  1  0.575  0.425  0.902  1.0
  O  O31  1  0.087  0.083  0.918  1.0
  O  O32  1  0.415  0.589  0.064  1.0
[/CIF]
.