The material structure described by Sr2LaI7 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to one I(1), one I(3), one I(4), one I(5), one I(7), two equivalent I(2), and two equivalent I(6) atoms. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one I(1), one I(2), one I(3), one I(4), one I(5), one I(6), and two equivalent I(7) atoms. La(1) is bonded in a distorted pentagonal bipyramidal geometry to one I(1), one I(2), one I(3), one I(4), one I(5), one I(6), and one I(7) atom. There are seven inequivalent I sites. In the first I site, I(1) is bonded in a trigonal non-coplanar geometry to one Sr(1), one Sr(2), and one La(1) atom. In the second I site, I(2) is bonded to one Sr(2), two equivalent Sr(1), and one La(1) atom to form a mixture of distorted corner and edge-sharing ISr3La tetrahedra. In the third I site, I(3) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one Sr(2), and one La(1) atom. In the fourth I site, I(4) is bonded in a 3-coordinate geometry to one Sr(1), one Sr(2), and one La(1) atom. In the fifth I site, I(5) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one Sr(2), and one La(1) atom. In the sixth I site, I(6) is bonded to one Sr(2), two equivalent Sr(1), and one La(1) atom to form a mixture of corner and edge-sharing ISr3La tetrahedra. In the seventh I site, I(7) is bonded to one Sr(1), two equivalent Sr(2), and one La(1) atom to form a mixture of corner and edge-sharing ISr3La tetrahedra. is represented by the CIF file [CIF]
data_Sr2LaI7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   17.598
_cell_length_b   7.901
_cell_length_c   11.956
_cell_angle_alpha   89.738
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1662.398
_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  0.560  0.284  0.677  1.0
  Sr  Sr1  1  0.218  0.294  0.553  1.0
  Sr  Sr2  1  0.940  0.284  0.177  1.0
  Sr  Sr3  1  0.282  0.294  0.053  1.0
  Sr  Sr4  1  0.718  0.706  0.947  1.0
  Sr  Sr5  1  0.060  0.716  0.823  1.0
  Sr  Sr6  1  0.782  0.706  0.447  1.0
  Sr  Sr7  1  0.440  0.716  0.323  1.0
  La  La8  1  0.869  0.216  0.724  1.0
  La  La9  1  0.631  0.216  0.224  1.0
  La  La10  1  0.369  0.784  0.776  1.0
  La  La11  1  0.131  0.784  0.276  1.0
  I  I12  1  0.214  0.000  0.777  1.0
  I  I13  1  0.397  0.002  0.556  1.0
  I  I14  1  0.286  0.000  0.277  1.0
  I  I15  1  0.103  0.002  0.056  1.0
  I  I16  1  0.426  0.148  0.877  1.0
  I  I17  1  0.074  0.148  0.377  1.0
  I  I18  1  0.642  0.307  0.963  1.0
  I  I19  1  0.858  0.307  0.463  1.0
  I  I20  1  0.043  0.320  0.709  1.0
  I  I21  1  0.457  0.320  0.209  1.0
  I  I22  1  0.895  0.502  0.928  1.0
  I  I23  1  0.739  0.506  0.696  1.0
  I  I24  1  0.605  0.502  0.428  1.0
  I  I25  1  0.761  0.506  0.196  1.0
  I  I26  1  0.239  0.494  0.804  1.0
  I  I27  1  0.395  0.498  0.572  1.0
  I  I28  1  0.261  0.494  0.304  1.0
  I  I29  1  0.105  0.498  0.072  1.0
  I  I30  1  0.543  0.680  0.791  1.0
  I  I31  1  0.957  0.680  0.291  1.0
  I  I32  1  0.142  0.693  0.537  1.0
  I  I33  1  0.358  0.693  0.037  1.0
  I  I34  1  0.926  0.852  0.623  1.0
  I  I35  1  0.574  0.852  0.123  1.0
  I  I36  1  0.897  0.998  0.944  1.0
  I  I37  1  0.714  1.000  0.723  1.0
  I  I38  1  0.603  0.998  0.444  1.0
  I  I39  1  0.786  1.000  0.223  1.0
[/CIF]
.
The material structure described by Sr2LaI7 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to one I(1), one I(3), one I(4), one I(5), one I(7), two equivalent I(2), and two equivalent I(6) atoms. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one I(1), one I(2), one I(3), one I(4), one I(5), one I(6), and two equivalent I(7) atoms. La(1) is bonded in a distorted pentagonal bipyramidal geometry to one I(1), one I(2), one I(3), one I(4), one I(5), one I(6), and one I(7) atom. There are seven inequivalent I sites. In the first I site, I(1) is bonded in a trigonal non-coplanar geometry to one Sr(1), one Sr(2), and one La(1) atom. In the second I site, I(2) is bonded to one Sr(2), two equivalent Sr(1), and one La(1) atom to form a mixture of distorted corner and edge-sharing ISr3La tetrahedra. In the third I site, I(3) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one Sr(2), and one La(1) atom. In the fourth I site, I(4) is bonded in a 3-coordinate geometry to one Sr(1), one Sr(2), and one La(1) atom. In the fifth I site, I(5) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one Sr(2), and one La(1) atom. In the sixth I site, I(6) is bonded to one Sr(2), two equivalent Sr(1), and one La(1) atom to form a mixture of corner and edge-sharing ISr3La tetrahedra. In the seventh I site, I(7) is bonded to one Sr(1), two equivalent Sr(2), and one La(1) atom to form a mixture of corner and edge-sharing ISr3La tetrahedra. is represented by the CIF file [CIF]
data_Sr2LaI7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   17.598
_cell_length_b   7.901
_cell_length_c   11.956
_cell_angle_alpha   89.738
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1662.398
_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  0.560  0.284  0.677  1.0
  Sr  Sr1  1  0.218  0.294  0.553  1.0
  Sr  Sr2  1  0.940  0.284  0.177  1.0
  Sr  Sr3  1  0.282  0.294  0.053  1.0
  Sr  Sr4  1  0.718  0.706  0.947  1.0
  Sr  Sr5  1  0.060  0.716  0.823  1.0
  Sr  Sr6  1  0.782  0.706  0.447  1.0
  Sr  Sr7  1  0.440  0.716  0.323  1.0
  La  La8  1  0.869  0.216  0.724  1.0
  La  La9  1  0.631  0.216  0.224  1.0
  La  La10  1  0.369  0.784  0.776  1.0
  La  La11  1  0.131  0.784  0.276  1.0
  I  I12  1  0.214  0.000  0.777  1.0
  I  I13  1  0.397  0.002  0.556  1.0
  I  I14  1  0.286  0.000  0.277  1.0
  I  I15  1  0.103  0.002  0.056  1.0
  I  I16  1  0.426  0.148  0.877  1.0
  I  I17  1  0.074  0.148  0.377  1.0
  I  I18  1  0.642  0.307  0.963  1.0
  I  I19  1  0.858  0.307  0.463  1.0
  I  I20  1  0.043  0.320  0.709  1.0
  I  I21  1  0.457  0.320  0.209  1.0
  I  I22  1  0.895  0.502  0.928  1.0
  I  I23  1  0.739  0.506  0.696  1.0
  I  I24  1  0.605  0.502  0.428  1.0
  I  I25  1  0.761  0.506  0.196  1.0
  I  I26  1  0.239  0.494  0.804  1.0
  I  I27  1  0.395  0.498  0.572  1.0
  I  I28  1  0.261  0.494  0.304  1.0
  I  I29  1  0.105  0.498  0.072  1.0
  I  I30  1  0.543  0.680  0.791  1.0
  I  I31  1  0.957  0.680  0.291  1.0
  I  I32  1  0.142  0.693  0.537  1.0
  I  I33  1  0.358  0.693  0.037  1.0
  I  I34  1  0.926  0.852  0.623  1.0
  I  I35  1  0.574  0.852  0.123  1.0
  I  I36  1  0.897  0.998  0.944  1.0
  I  I37  1  0.714  1.000  0.723  1.0
  I  I38  1  0.603  0.998  0.444  1.0
  I  I39  1  0.786  1.000  0.223  1.0
[/CIF]
.