The structure described by Sr2YI7 crystallizes in the monoclinic P2_1 space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 7-coordinate geometry to one I(1), one I(11), one I(12), one I(14), one I(3), one I(8), and one I(9) atom. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one I(10), one I(13), one I(3), one I(4), one I(6), one I(7), and one I(9) atom. In the third Sr site, Sr(3) is bonded in a 8-coordinate geometry to one I(1), one I(10), one I(14), one I(2), one I(4), one I(6), one I(8), and one I(9) atom. In the fourth Sr site, Sr(4) is bonded to one I(10), one I(11), one I(12), one I(13), one I(5), and one I(7) atom to form distorted SrI6 pentagonal pyramids that share  a cornercorner with one Y(1)I6 octahedra,  a cornercorner with one Y(2)I6 octahedra, and  a faceface with one Y(1)I6 octahedra. The corner-sharing octahedral tilt angles range from 60-63°. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to one I(11), one I(13), one I(3), one I(5), one I(6), and one I(7) atom to form YI6 octahedra that share  a cornercorner with one Sr(4)I6 pentagonal pyramid and  a faceface with one Sr(4)I6 pentagonal pyramid. In the second Y site, Y(2) is bonded to one I(1), one I(12), one I(14), one I(2), one I(4), and one I(8) atom to form YI6 octahedra that share  a cornercorner with one Sr(4)I6 pentagonal pyramid. There are fourteen inequivalent I sites. In the first I site, I(1) is bonded in a distorted L-shaped geometry to one Sr(1), one Sr(3), and one Y(2) atom. In the second I site, I(2) is bonded in an L-shaped geometry to one Sr(3) and one Y(2) atom. In the third I site, I(3) is bonded in a 3-coordinate geometry to one Sr(1), one Sr(2), and one Y(1) atom. In the fourth I site, I(4) is bonded in a distorted trigonal planar geometry to one Sr(2), one Sr(3), and one Y(2) atom. In the fifth I site, I(5) is bonded in a bent 120 degrees geometry to one Sr(4) and one Y(1) atom. In the sixth I site, I(6) is bonded in a distorted trigonal non-coplanar geometry to one Sr(2), one Sr(3), and one Y(1) atom. In the seventh I site, I(7) is bonded in a 3-coordinate geometry to one Sr(2), one Sr(4), and one Y(1) atom. In the eighth I site, I(8) is bonded in a distorted T-shaped geometry to one Sr(1), one Sr(3), and one Y(2) atom. In the ninth I site, I(9) is bonded in a trigonal non-coplanar geometry to one Sr(1), one Sr(2), and one Sr(3) atom. In the tenth I site, I(10) is bonded in a T-shaped geometry to one Sr(2), one Sr(3), and one Sr(4) atom. In the eleventh I site, I(11) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one Sr(4), and one Y(1) atom. In the twelfth I site, I(12) is bonded in a distorted bent 120 degrees geometry to one Sr(1), one Sr(4), and one Y(2) atom. In the thirteenth I site, I(13) is bonded in a distorted T-shaped geometry to one Sr(2), one Sr(4), and one Y(1) atom. In the fourteenth I site, I(14) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one Sr(3), and one Y(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr2YI7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.610
_cell_length_b   8.311
_cell_length_c   14.912
_cell_angle_alpha   79.379
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1779.617
_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  0.538  0.751  0.772  1.0
  Sr  Sr1  1  0.128  0.758  0.655  1.0
  Sr  Sr2  1  0.797  0.771  0.158  1.0
  Sr  Sr3  1  0.369  0.621  0.267  1.0
  Sr  Sr4  1  0.869  0.379  0.733  1.0
  Sr  Sr5  1  0.297  0.229  0.842  1.0
  Sr  Sr6  1  0.628  0.242  0.345  1.0
  Sr  Sr7  1  0.038  0.249  0.228  1.0
  Y  Y8  1  0.846  0.852  0.554  1.0
  Y  Y9  1  0.075  0.843  0.054  1.0
  Y  Y10  1  0.575  0.157  0.946  1.0
  Y  Y11  1  0.346  0.148  0.446  1.0
  I  I12  1  0.695  0.886  0.904  1.0
  I  I13  1  0.419  0.926  0.997  1.0
  I  I14  1  0.512  0.955  0.512  1.0
  I  I15  1  0.164  0.884  0.866  1.0
  I  I16  1  0.253  0.845  0.404  1.0
  I  I17  1  0.750  0.880  0.371  1.0
  I  I18  1  0.918  0.792  0.750  1.0
  I  I19  1  0.003  0.835  0.251  1.0
  I  I20  1  0.340  0.607  0.701  1.0
  I  I21  1  0.588  0.604  0.200  1.0
  I  I22  1  0.690  0.615  0.627  1.0
  I  I23  1  0.716  0.422  0.888  1.0
  I  I24  1  0.967  0.551  0.540  1.0
  I  I25  1  0.445  0.444  0.953  1.0
  I  I26  1  0.945  0.556  0.047  1.0
  I  I27  1  0.467  0.449  0.460  1.0
  I  I28  1  0.216  0.578  0.112  1.0
  I  I29  1  0.190  0.385  0.373  1.0
  I  I30  1  0.088  0.396  0.800  1.0
  I  I31  1  0.840  0.393  0.299  1.0
  I  I32  1  0.503  0.165  0.749  1.0
  I  I33  1  0.418  0.208  0.250  1.0
  I  I34  1  0.250  0.120  0.629  1.0
  I  I35  1  0.753  0.155  0.596  1.0
  I  I36  1  0.664  0.116  0.134  1.0
  I  I37  1  0.012  0.045  0.488  1.0
  I  I38  1  0.919  0.074  0.003  1.0
  I  I39  1  0.195  0.114  0.096  1.0
[/CIF]
.
The structure described by Sr2YI7 crystallizes in the monoclinic P2_1 space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 7-coordinate geometry to one I(1), one I(11), one I(12), one I(14), one I(3), one I(8), and one I(9) atom. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one I(10), one I(13), one I(3), one I(4), one I(6), one I(7), and one I(9) atom. In the third Sr site, Sr(3) is bonded in a 8-coordinate geometry to one I(1), one I(10), one I(14), one I(2), one I(4), one I(6), one I(8), and one I(9) atom. In the fourth Sr site, Sr(4) is bonded to one I(10), one I(11), one I(12), one I(13), one I(5), and one I(7) atom to form distorted SrI6 pentagonal pyramids that share  a cornercorner with one Y(1)I6 octahedra,  a cornercorner with one Y(2)I6 octahedra, and  a faceface with one Y(1)I6 octahedra. The corner-sharing octahedral tilt angles range from 60-63°. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to one I(11), one I(13), one I(3), one I(5), one I(6), and one I(7) atom to form YI6 octahedra that share  a cornercorner with one Sr(4)I6 pentagonal pyramid and  a faceface with one Sr(4)I6 pentagonal pyramid. In the second Y site, Y(2) is bonded to one I(1), one I(12), one I(14), one I(2), one I(4), and one I(8) atom to form YI6 octahedra that share  a cornercorner with one Sr(4)I6 pentagonal pyramid. There are fourteen inequivalent I sites. In the first I site, I(1) is bonded in a distorted L-shaped geometry to one Sr(1), one Sr(3), and one Y(2) atom. In the second I site, I(2) is bonded in an L-shaped geometry to one Sr(3) and one Y(2) atom. In the third I site, I(3) is bonded in a 3-coordinate geometry to one Sr(1), one Sr(2), and one Y(1) atom. In the fourth I site, I(4) is bonded in a distorted trigonal planar geometry to one Sr(2), one Sr(3), and one Y(2) atom. In the fifth I site, I(5) is bonded in a bent 120 degrees geometry to one Sr(4) and one Y(1) atom. In the sixth I site, I(6) is bonded in a distorted trigonal non-coplanar geometry to one Sr(2), one Sr(3), and one Y(1) atom. In the seventh I site, I(7) is bonded in a 3-coordinate geometry to one Sr(2), one Sr(4), and one Y(1) atom. In the eighth I site, I(8) is bonded in a distorted T-shaped geometry to one Sr(1), one Sr(3), and one Y(2) atom. In the ninth I site, I(9) is bonded in a trigonal non-coplanar geometry to one Sr(1), one Sr(2), and one Sr(3) atom. In the tenth I site, I(10) is bonded in a T-shaped geometry to one Sr(2), one Sr(3), and one Sr(4) atom. In the eleventh I site, I(11) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one Sr(4), and one Y(1) atom. In the twelfth I site, I(12) is bonded in a distorted bent 120 degrees geometry to one Sr(1), one Sr(4), and one Y(2) atom. In the thirteenth I site, I(13) is bonded in a distorted T-shaped geometry to one Sr(2), one Sr(4), and one Y(1) atom. In the fourteenth I site, I(14) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one Sr(3), and one Y(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr2YI7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.610
_cell_length_b   8.311
_cell_length_c   14.912
_cell_angle_alpha   79.379
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1779.617
_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  0.538  0.751  0.772  1.0
  Sr  Sr1  1  0.128  0.758  0.655  1.0
  Sr  Sr2  1  0.797  0.771  0.158  1.0
  Sr  Sr3  1  0.369  0.621  0.267  1.0
  Sr  Sr4  1  0.869  0.379  0.733  1.0
  Sr  Sr5  1  0.297  0.229  0.842  1.0
  Sr  Sr6  1  0.628  0.242  0.345  1.0
  Sr  Sr7  1  0.038  0.249  0.228  1.0
  Y  Y8  1  0.846  0.852  0.554  1.0
  Y  Y9  1  0.075  0.843  0.054  1.0
  Y  Y10  1  0.575  0.157  0.946  1.0
  Y  Y11  1  0.346  0.148  0.446  1.0
  I  I12  1  0.695  0.886  0.904  1.0
  I  I13  1  0.419  0.926  0.997  1.0
  I  I14  1  0.512  0.955  0.512  1.0
  I  I15  1  0.164  0.884  0.866  1.0
  I  I16  1  0.253  0.845  0.404  1.0
  I  I17  1  0.750  0.880  0.371  1.0
  I  I18  1  0.918  0.792  0.750  1.0
  I  I19  1  0.003  0.835  0.251  1.0
  I  I20  1  0.340  0.607  0.701  1.0
  I  I21  1  0.588  0.604  0.200  1.0
  I  I22  1  0.690  0.615  0.627  1.0
  I  I23  1  0.716  0.422  0.888  1.0
  I  I24  1  0.967  0.551  0.540  1.0
  I  I25  1  0.445  0.444  0.953  1.0
  I  I26  1  0.945  0.556  0.047  1.0
  I  I27  1  0.467  0.449  0.460  1.0
  I  I28  1  0.216  0.578  0.112  1.0
  I  I29  1  0.190  0.385  0.373  1.0
  I  I30  1  0.088  0.396  0.800  1.0
  I  I31  1  0.840  0.393  0.299  1.0
  I  I32  1  0.503  0.165  0.749  1.0
  I  I33  1  0.418  0.208  0.250  1.0
  I  I34  1  0.250  0.120  0.629  1.0
  I  I35  1  0.753  0.155  0.596  1.0
  I  I36  1  0.664  0.116  0.134  1.0
  I  I37  1  0.012  0.045  0.488  1.0
  I  I38  1  0.919  0.074  0.003  1.0
  I  I39  1  0.195  0.114  0.096  1.0
[/CIF]
.