The compound described by Sr3As4 crystallizes in the triclinic P1 space group. There are six inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 8-coordinate geometry to one As(1), one As(2), one As(3), one As(4), one As(5), one As(8), and two equivalent As(6) atoms. In the second Sr site, Sr(2) is bonded to one As(1), one As(2), one As(3), one As(4), one As(6), one As(7), and two equivalent As(5) atoms to form a mixture of corner and edge-sharing SrAs8 hexagonal bipyramids. In the third Sr site, Sr(3) is bonded in a 8-coordinate geometry to one As(1), one As(2), one As(3), one As(4), one As(5), one As(8), and two equivalent As(7) atoms. In the fourth Sr site, Sr(4) is bonded to one As(1), one As(2), one As(3), one As(4), one As(6), one As(7), and two equivalent As(8) atoms to form a mixture of corner and edge-sharing SrAs8 hexagonal bipyramids. In the fifth Sr site, Sr(5) is bonded in a 8-coordinate geometry to one As(5), one As(6), one As(7), one As(8), two equivalent As(1), and two equivalent As(2) atoms. In the sixth Sr site, Sr(6) is bonded in a 8-coordinate geometry to one As(5), one As(6), one As(7), one As(8), two equivalent As(3), and two equivalent As(4) atoms. There are eight inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Sr(4), two equivalent Sr(5), one As(2), and one As(6) atom. In the second As site, As(2) is bonded in a 8-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Sr(4), two equivalent Sr(5), one As(1), and one As(5) atom. In the third As site, As(3) is bonded in a 8-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Sr(4), two equivalent Sr(6), one As(4), and one As(7) atom. In the fourth As site, As(4) is bonded in a 8-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Sr(4), two equivalent Sr(6), one As(3), and one As(8) atom. In the fifth As site, As(5) is bonded in a 7-coordinate geometry to one Sr(1), one Sr(3), one Sr(5), one Sr(6), two equivalent Sr(2), and one As(2) atom. In the sixth As site, As(6) is bonded in a 7-coordinate geometry to one Sr(2), one Sr(4), one Sr(5), one Sr(6), two equivalent Sr(1), and one As(1) atom. In the seventh As site, As(7) is bonded in a 7-coordinate geometry to one Sr(2), one Sr(4), one Sr(5), one Sr(6), two equivalent Sr(3), and one As(3) atom. In the eighth As site, As(8) is bonded in a 7-coordinate geometry to one Sr(1), one Sr(3), one Sr(5), one Sr(6), two equivalent Sr(4), and one As(4) atom. is represented by the CIF file [CIF]
data_Sr3As4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.744
_cell_length_b   9.525
_cell_length_c   8.090
_cell_angle_alpha   83.197
_cell_angle_beta   53.645
_cell_angle_gamma   43.158
_symmetry_Int_Tables_number   1
_cell_volume   409.671
_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  0.894  0.445  0.101  1.0
  Sr  Sr1  1  0.555  0.114  0.453  1.0
  Sr  Sr2  1  0.136  0.693  0.368  1.0
  Sr  Sr3  1  0.807  0.357  0.684  1.0
  Sr  Sr4  1  0.513  0.988  0.991  1.0
  Sr  Sr5  1  0.252  0.743  0.746  1.0
  As  As6  1  0.924  0.584  0.400  1.0
  As  As7  1  0.088  0.405  0.591  1.0
  As  As8  1  0.846  0.155  0.326  1.0
  As  As9  1  0.666  0.334  0.163  1.0
  As  As10  1  0.969  0.687  0.862  1.0
  As  As11  1  0.488  0.851  0.677  1.0
  As  As12  1  0.566  0.279  0.766  1.0
  As  As13  1  0.388  0.771  0.281  1.0
[/CIF]
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The compound described by Sr3As4 crystallizes in the triclinic P1 space group. There are six inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 8-coordinate geometry to one As(1), one As(2), one As(3), one As(4), one As(5), one As(8), and two equivalent As(6) atoms. In the second Sr site, Sr(2) is bonded to one As(1), one As(2), one As(3), one As(4), one As(6), one As(7), and two equivalent As(5) atoms to form a mixture of corner and edge-sharing SrAs8 hexagonal bipyramids. In the third Sr site, Sr(3) is bonded in a 8-coordinate geometry to one As(1), one As(2), one As(3), one As(4), one As(5), one As(8), and two equivalent As(7) atoms. In the fourth Sr site, Sr(4) is bonded to one As(1), one As(2), one As(3), one As(4), one As(6), one As(7), and two equivalent As(8) atoms to form a mixture of corner and edge-sharing SrAs8 hexagonal bipyramids. In the fifth Sr site, Sr(5) is bonded in a 8-coordinate geometry to one As(5), one As(6), one As(7), one As(8), two equivalent As(1), and two equivalent As(2) atoms. In the sixth Sr site, Sr(6) is bonded in a 8-coordinate geometry to one As(5), one As(6), one As(7), one As(8), two equivalent As(3), and two equivalent As(4) atoms. There are eight inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Sr(4), two equivalent Sr(5), one As(2), and one As(6) atom. In the second As site, As(2) is bonded in a 8-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Sr(4), two equivalent Sr(5), one As(1), and one As(5) atom. In the third As site, As(3) is bonded in a 8-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Sr(4), two equivalent Sr(6), one As(4), and one As(7) atom. In the fourth As site, As(4) is bonded in a 8-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Sr(4), two equivalent Sr(6), one As(3), and one As(8) atom. In the fifth As site, As(5) is bonded in a 7-coordinate geometry to one Sr(1), one Sr(3), one Sr(5), one Sr(6), two equivalent Sr(2), and one As(2) atom. In the sixth As site, As(6) is bonded in a 7-coordinate geometry to one Sr(2), one Sr(4), one Sr(5), one Sr(6), two equivalent Sr(1), and one As(1) atom. In the seventh As site, As(7) is bonded in a 7-coordinate geometry to one Sr(2), one Sr(4), one Sr(5), one Sr(6), two equivalent Sr(3), and one As(3) atom. In the eighth As site, As(8) is bonded in a 7-coordinate geometry to one Sr(1), one Sr(3), one Sr(5), one Sr(6), two equivalent Sr(4), and one As(4) atom. is represented by the CIF file [CIF]
data_Sr3As4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.744
_cell_length_b   9.525
_cell_length_c   8.090
_cell_angle_alpha   83.197
_cell_angle_beta   53.645
_cell_angle_gamma   43.158
_symmetry_Int_Tables_number   1
_cell_volume   409.671
_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  0.894  0.445  0.101  1.0
  Sr  Sr1  1  0.555  0.114  0.453  1.0
  Sr  Sr2  1  0.136  0.693  0.368  1.0
  Sr  Sr3  1  0.807  0.357  0.684  1.0
  Sr  Sr4  1  0.513  0.988  0.991  1.0
  Sr  Sr5  1  0.252  0.743  0.746  1.0
  As  As6  1  0.924  0.584  0.400  1.0
  As  As7  1  0.088  0.405  0.591  1.0
  As  As8  1  0.846  0.155  0.326  1.0
  As  As9  1  0.666  0.334  0.163  1.0
  As  As10  1  0.969  0.687  0.862  1.0
  As  As11  1  0.488  0.851  0.677  1.0
  As  As12  1  0.566  0.279  0.766  1.0
  As  As13  1  0.388  0.771  0.281  1.0
[/CIF]
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