The compound described by Sr3Ga2As4 crystallizes in the monoclinic C2/c space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 6-coordinate geometry to two equivalent As(2) and four equivalent As(1) atoms. In the second Sr site, Sr(2) is bonded to two equivalent As(1) and four equivalent As(2) atoms to form distorted SrAs6 octahedra that share corners with four equivalent Ga(1)As4 tetrahedra, edges with two equivalent Sr(2)As6 octahedra, and edges with four equivalent Ga(1)As4 tetrahedra. Ga(1) is bonded to two equivalent As(1) and two equivalent As(2) atoms to form distorted GaAs4 tetrahedra that share corners with two equivalent Sr(2)As6 octahedra, corners with two equivalent Ga(1)As4 tetrahedra, edges with two equivalent Sr(2)As6 octahedra, and  an edgeedge with one Ga(1)As4 tetrahedra. The corner-sharing octahedral tilt angles range from 31-56°. There are two inequivalent As sites. In the first As site, As(1) is bonded to one Sr(2), four equivalent Sr(1), and two equivalent Ga(1) atoms to form distorted AsSr5Ga2 pentagonal bipyramids that share corners with two equivalent As(1)Sr5Ga2 pentagonal bipyramids, corners with four equivalent As(2)Sr4Ga2 pentagonal pyramids, edges with five equivalent As(1)Sr5Ga2 pentagonal bipyramids, edges with six equivalent As(2)Sr4Ga2 pentagonal pyramids, and  a faceface with one As(1)Sr5Ga2 pentagonal bipyramid. In the second As site, As(2) is bonded to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Ga(1) atoms to form distorted AsSr4Ga2 pentagonal pyramids that share corners with four equivalent As(1)Sr5Ga2 pentagonal bipyramids, corners with two equivalent As(2)Sr4Ga2 pentagonal pyramids, edges with six equivalent As(1)Sr5Ga2 pentagonal bipyramids, and edges with four equivalent As(2)Sr4Ga2 pentagonal pyramids. is represented by the CIF card [CIF]
data_Sr3(GaAs2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.583
_cell_length_b   8.583
_cell_length_c   6.832
_cell_angle_alpha   89.839
_cell_angle_beta   89.839
_cell_angle_gamma   75.626
_symmetry_Int_Tables_number   1
_cell_volume   487.590
_cell_formula_units_Z   2
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  0.749  0.004  0.965  1.0
  Sr  Sr1  1  0.996  0.251  0.535  1.0
  Sr  Sr2  1  0.251  0.996  0.035  1.0
  Sr  Sr3  1  0.004  0.749  0.465  1.0
  Sr  Sr4  1  0.600  0.400  0.250  1.0
  Sr  Sr5  1  0.400  0.600  0.750  1.0
  Ga  Ga6  1  0.583  0.825  0.417  1.0
  Ga  Ga7  1  0.175  0.417  0.083  1.0
  Ga  Ga8  1  0.417  0.175  0.583  1.0
  Ga  Ga9  1  0.825  0.583  0.917  1.0
  As  As10  1  0.707  0.058  0.477  1.0
  As  As11  1  0.942  0.293  0.023  1.0
  As  As12  1  0.293  0.942  0.523  1.0
  As  As13  1  0.058  0.707  0.977  1.0
  As  As14  1  0.572  0.741  0.072  1.0
  As  As15  1  0.259  0.428  0.428  1.0
  As  As16  1  0.428  0.259  0.928  1.0
  As  As17  1  0.741  0.572  0.572  1.0
[/CIF]
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The compound described by Sr3Ga2As4 crystallizes in the monoclinic C2/c space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 6-coordinate geometry to two equivalent As(2) and four equivalent As(1) atoms. In the second Sr site, Sr(2) is bonded to two equivalent As(1) and four equivalent As(2) atoms to form distorted SrAs6 octahedra that share corners with four equivalent Ga(1)As4 tetrahedra, edges with two equivalent Sr(2)As6 octahedra, and edges with four equivalent Ga(1)As4 tetrahedra. Ga(1) is bonded to two equivalent As(1) and two equivalent As(2) atoms to form distorted GaAs4 tetrahedra that share corners with two equivalent Sr(2)As6 octahedra, corners with two equivalent Ga(1)As4 tetrahedra, edges with two equivalent Sr(2)As6 octahedra, and  an edgeedge with one Ga(1)As4 tetrahedra. The corner-sharing octahedral tilt angles range from 31-56°. There are two inequivalent As sites. In the first As site, As(1) is bonded to one Sr(2), four equivalent Sr(1), and two equivalent Ga(1) atoms to form distorted AsSr5Ga2 pentagonal bipyramids that share corners with two equivalent As(1)Sr5Ga2 pentagonal bipyramids, corners with four equivalent As(2)Sr4Ga2 pentagonal pyramids, edges with five equivalent As(1)Sr5Ga2 pentagonal bipyramids, edges with six equivalent As(2)Sr4Ga2 pentagonal pyramids, and  a faceface with one As(1)Sr5Ga2 pentagonal bipyramid. In the second As site, As(2) is bonded to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Ga(1) atoms to form distorted AsSr4Ga2 pentagonal pyramids that share corners with four equivalent As(1)Sr5Ga2 pentagonal bipyramids, corners with two equivalent As(2)Sr4Ga2 pentagonal pyramids, edges with six equivalent As(1)Sr5Ga2 pentagonal bipyramids, and edges with four equivalent As(2)Sr4Ga2 pentagonal pyramids. is represented by the CIF card [CIF]
data_Sr3(GaAs2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.583
_cell_length_b   8.583
_cell_length_c   6.832
_cell_angle_alpha   89.839
_cell_angle_beta   89.839
_cell_angle_gamma   75.626
_symmetry_Int_Tables_number   1
_cell_volume   487.590
_cell_formula_units_Z   2
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  0.749  0.004  0.965  1.0
  Sr  Sr1  1  0.996  0.251  0.535  1.0
  Sr  Sr2  1  0.251  0.996  0.035  1.0
  Sr  Sr3  1  0.004  0.749  0.465  1.0
  Sr  Sr4  1  0.600  0.400  0.250  1.0
  Sr  Sr5  1  0.400  0.600  0.750  1.0
  Ga  Ga6  1  0.583  0.825  0.417  1.0
  Ga  Ga7  1  0.175  0.417  0.083  1.0
  Ga  Ga8  1  0.417  0.175  0.583  1.0
  Ga  Ga9  1  0.825  0.583  0.917  1.0
  As  As10  1  0.707  0.058  0.477  1.0
  As  As11  1  0.942  0.293  0.023  1.0
  As  As12  1  0.293  0.942  0.523  1.0
  As  As13  1  0.058  0.707  0.977  1.0
  As  As14  1  0.572  0.741  0.072  1.0
  As  As15  1  0.259  0.428  0.428  1.0
  As  As16  1  0.428  0.259  0.928  1.0
  As  As17  1  0.741  0.572  0.572  1.0
[/CIF]
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