The compound described by Al2Si2Sr3 crystallizes in the orthorhombic Immm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to eight equivalent Al(1) and four equivalent Si(1) atoms to form a mixture of face and edge-sharing SrAl8Si4 cuboctahedra. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to two equivalent Al(1) and five equivalent Si(1) atoms. Al(1) is bonded in a 9-coordinate geometry to two equivalent Sr(2), four equivalent Sr(1), one Al(1), and two equivalent Si(1) atoms. Si(1) is bonded in a 9-coordinate geometry to two equivalent Sr(1), five equivalent Sr(2), and two equivalent Al(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr3(AlSi)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.206
_cell_length_b   4.850
_cell_length_c   10.115
_cell_angle_alpha   103.865
_cell_angle_beta   102.012
_cell_angle_gamma   89.999
_symmetry_Int_Tables_number   1
_cell_volume   195.683
_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  0.500  0.000  0.000  1.0
  Sr  Sr1  1  0.815  0.815  0.630  1.0
  Sr  Sr2  1  0.185  0.185  0.370  1.0
  Al  Al3  1  0.067  0.567  0.134  1.0
  Al  Al4  1  0.933  0.433  0.866  1.0
  Si  Si5  1  0.639  0.639  0.277  1.0
  Si  Si6  1  0.361  0.361  0.723  1.0
[/CIF]
.
The compound described by Al2Si2Sr3 crystallizes in the orthorhombic Immm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to eight equivalent Al(1) and four equivalent Si(1) atoms to form a mixture of face and edge-sharing SrAl8Si4 cuboctahedra. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to two equivalent Al(1) and five equivalent Si(1) atoms. Al(1) is bonded in a 9-coordinate geometry to two equivalent Sr(2), four equivalent Sr(1), one Al(1), and two equivalent Si(1) atoms. Si(1) is bonded in a 9-coordinate geometry to two equivalent Sr(1), five equivalent Sr(2), and two equivalent Al(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr3(AlSi)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.206
_cell_length_b   4.850
_cell_length_c   10.115
_cell_angle_alpha   103.865
_cell_angle_beta   102.012
_cell_angle_gamma   89.999
_symmetry_Int_Tables_number   1
_cell_volume   195.683
_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  0.500  0.000  0.000  1.0
  Sr  Sr1  1  0.815  0.815  0.630  1.0
  Sr  Sr2  1  0.185  0.185  0.370  1.0
  Al  Al3  1  0.067  0.567  0.134  1.0
  Al  Al4  1  0.933  0.433  0.866  1.0
  Si  Si5  1  0.639  0.639  0.277  1.0
  Si  Si6  1  0.361  0.361  0.723  1.0
[/CIF]
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