The structure described by Sr2Cr2GaAlO7 crystallizes in the triclinic P1 space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 8-coordinate geometry to one O(1), one O(11), one O(13), one O(14), one O(3), one O(7), and two equivalent O(12) atoms. In the second Sr site, Sr(2) is bonded in a 5-coordinate geometry to one O(2), one O(4), one O(5), one O(8), and two equivalent O(10) atoms. In the third Sr site, Sr(3) is bonded in a 8-coordinate geometry to one O(1), one O(12), one O(13), one O(14), one O(2), one O(3), and two equivalent O(11) atoms. In the fourth Sr site, Sr(4) is bonded in a 6-coordinate geometry to one O(10), one O(6), one O(7), one O(9), and two equivalent O(4) atoms. There are four inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(10), one O(5), one O(6), one O(8), and one O(9) atom to form distorted CrO5 square pyramids that share corners with four equivalent Cr(3)O5 square pyramids and  a cornercorner with one Ga(1)O4 tetrahedra. In the second Cr site, Cr(2) is bonded to one O(1), one O(11), one O(13), one O(14), and one O(3) atom to form distorted CrO5 square pyramids that share corners with four equivalent Cr(4)O5 square pyramids and  a cornercorner with one Ga(1)O4 tetrahedra. In the third Cr site, Cr(3) is bonded to one O(4), one O(5), one O(6), one O(8), and one O(9) atom to form distorted CrO5 square pyramids that share corners with four equivalent Cr(1)O5 square pyramids and  a cornercorner with one Ga(2)O4 tetrahedra. In the fourth Cr site, Cr(4) is bonded to one O(1), one O(12), one O(13), one O(14), and one O(3) atom to form distorted CrO5 square pyramids that share corners with four equivalent Cr(2)O5 square pyramids and  a cornercorner with one Ga(2)O4 tetrahedra. There are two inequivalent Ga sites. In the first Ga site, Ga(1) is bonded to one O(10), one O(11), one O(2), and one O(7) atom to form GaO4 tetrahedra that share  a cornercorner with one Cr(1)O5 square pyramid,  a cornercorner with one Cr(2)O5 square pyramid, and corners with two equivalent Ga(2)O4 tetrahedra. In the second Ga site, Ga(2) is bonded to one O(12), one O(2), one O(4), and one O(7) atom to form GaO4 tetrahedra that share  a cornercorner with one Cr(3)O5 square pyramid,  a cornercorner with one Cr(4)O5 square pyramid, and corners with two equivalent Ga(1)O4 tetrahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a distorted see-saw-like geometry to one O(1), one O(3), one O(6), and one O(9) atom. In the second Al site, Al(2) is bonded in a distorted see-saw-like geometry to one O(13), one O(14), one O(5), and one O(8) atom. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Sr(1), one Sr(3), one Cr(2), one Cr(4), and one Al(1) atom. In the second O site, O(2) is bonded to one Sr(2), one Sr(3), one Ga(1), and one Ga(2) atom to form distorted OSr2Ga2 tetrahedra that share corners with two equivalent O(7)Sr2Ga2 tetrahedra and  a cornercorner with one O(8)SrAlCr2 trigonal pyramid. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(3), one Cr(2), one Cr(4), and one Al(1) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Sr(2), two equivalent Sr(4), one Cr(3), and one Ga(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Sr(2), one Cr(1), one Cr(3), and one Al(2) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Sr(4), one Cr(1), one Cr(3), and one Al(1) atom. In the seventh O site, O(7) is bonded to one Sr(1), one Sr(4), one Ga(1), and one Ga(2) atom to form distorted corner-sharing OSr2Ga2 tetrahedra. In the eighth O site, O(8) is bonded to one Sr(2), one Cr(1), one Cr(3), and one Al(2) atom to form distorted corner-sharing OSrAlCr2 trigonal pyramids. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Sr(4), one Cr(1), one Cr(3), and one Al(1) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Sr(4), two equivalent Sr(2), one Cr(1), and one Ga(1) atom. In the eleventh O site, O(11) is bonded in a 5-coordinate geometry to one Sr(1), two equivalent Sr(3), one Cr(2), and one Ga(1) atom. In the twelfth O site, O(12) is bonded in a 5-coordinate geometry to one Sr(3), two equivalent Sr(1), one Cr(4), and one Ga(2) atom. In the thirteenth O site, O(13) is bonded in a 3-coordinate geometry to one Sr(1), one Sr(3), one Cr(2), one Cr(4), and one Al(2) atom. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(3), one Cr(2), one Cr(4), and one Al(2) atom. is represented by the CIF card [CIF]
data_Sr2AlCr2GaO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.470
_cell_length_b   5.878
_cell_length_c   11.506
_cell_angle_alpha   99.077
_cell_angle_beta   103.162
_cell_angle_gamma   89.926
_symmetry_Int_Tables_number   1
_cell_volume   355.522
_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  0.143  0.219  0.298  1.0
  Sr  Sr1  1  0.826  0.787  0.697  1.0
  Sr  Sr2  1  0.656  0.664  0.296  1.0
  Sr  Sr3  1  0.328  0.345  0.692  1.0
  Al  Al4  1  0.516  0.406  0.992  1.0
  Al  Al5  1  0.977  0.934  0.001  1.0
  Cr  Cr6  1  0.426  0.875  0.879  1.0
  Cr  Cr7  1  0.077  0.628  0.140  1.0
  Cr  Cr8  1  0.939  0.377  0.878  1.0
  Cr  Cr9  1  0.571  0.126  0.145  1.0
  Ga  Ga10  1  0.213  0.825  0.499  1.0
  Ga  Ga11  1  0.715  0.181  0.499  1.0
  O  O12  1  0.819  0.352  0.102  1.0
  O  O13  1  0.869  0.891  0.498  1.0
  O  O14  1  0.371  0.431  0.120  1.0
  O  O15  1  0.842  0.358  0.649  1.0
  O  O16  1  0.764  0.059  0.886  1.0
  O  O17  1  0.276  0.203  0.887  1.0
  O  O18  1  0.368  0.115  0.496  1.0
  O  O19  1  0.100  0.711  0.897  1.0
  O  O20  1  0.605  0.555  0.883  1.0
  O  O21  1  0.343  0.747  0.650  1.0
  O  O22  1  0.204  0.646  0.350  1.0
  O  O23  1  0.710  0.266  0.351  1.0
  O  O24  1  0.792  0.856  0.109  1.0
  O  O25  1  0.252  0.945  0.129  1.0
[/CIF]
.
The structure described by Sr2Cr2GaAlO7 crystallizes in the triclinic P1 space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 8-coordinate geometry to one O(1), one O(11), one O(13), one O(14), one O(3), one O(7), and two equivalent O(12) atoms. In the second Sr site, Sr(2) is bonded in a 5-coordinate geometry to one O(2), one O(4), one O(5), one O(8), and two equivalent O(10) atoms. In the third Sr site, Sr(3) is bonded in a 8-coordinate geometry to one O(1), one O(12), one O(13), one O(14), one O(2), one O(3), and two equivalent O(11) atoms. In the fourth Sr site, Sr(4) is bonded in a 6-coordinate geometry to one O(10), one O(6), one O(7), one O(9), and two equivalent O(4) atoms. There are four inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(10), one O(5), one O(6), one O(8), and one O(9) atom to form distorted CrO5 square pyramids that share corners with four equivalent Cr(3)O5 square pyramids and  a cornercorner with one Ga(1)O4 tetrahedra. In the second Cr site, Cr(2) is bonded to one O(1), one O(11), one O(13), one O(14), and one O(3) atom to form distorted CrO5 square pyramids that share corners with four equivalent Cr(4)O5 square pyramids and  a cornercorner with one Ga(1)O4 tetrahedra. In the third Cr site, Cr(3) is bonded to one O(4), one O(5), one O(6), one O(8), and one O(9) atom to form distorted CrO5 square pyramids that share corners with four equivalent Cr(1)O5 square pyramids and  a cornercorner with one Ga(2)O4 tetrahedra. In the fourth Cr site, Cr(4) is bonded to one O(1), one O(12), one O(13), one O(14), and one O(3) atom to form distorted CrO5 square pyramids that share corners with four equivalent Cr(2)O5 square pyramids and  a cornercorner with one Ga(2)O4 tetrahedra. There are two inequivalent Ga sites. In the first Ga site, Ga(1) is bonded to one O(10), one O(11), one O(2), and one O(7) atom to form GaO4 tetrahedra that share  a cornercorner with one Cr(1)O5 square pyramid,  a cornercorner with one Cr(2)O5 square pyramid, and corners with two equivalent Ga(2)O4 tetrahedra. In the second Ga site, Ga(2) is bonded to one O(12), one O(2), one O(4), and one O(7) atom to form GaO4 tetrahedra that share  a cornercorner with one Cr(3)O5 square pyramid,  a cornercorner with one Cr(4)O5 square pyramid, and corners with two equivalent Ga(1)O4 tetrahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a distorted see-saw-like geometry to one O(1), one O(3), one O(6), and one O(9) atom. In the second Al site, Al(2) is bonded in a distorted see-saw-like geometry to one O(13), one O(14), one O(5), and one O(8) atom. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Sr(1), one Sr(3), one Cr(2), one Cr(4), and one Al(1) atom. In the second O site, O(2) is bonded to one Sr(2), one Sr(3), one Ga(1), and one Ga(2) atom to form distorted OSr2Ga2 tetrahedra that share corners with two equivalent O(7)Sr2Ga2 tetrahedra and  a cornercorner with one O(8)SrAlCr2 trigonal pyramid. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(3), one Cr(2), one Cr(4), and one Al(1) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Sr(2), two equivalent Sr(4), one Cr(3), and one Ga(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Sr(2), one Cr(1), one Cr(3), and one Al(2) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Sr(4), one Cr(1), one Cr(3), and one Al(1) atom. In the seventh O site, O(7) is bonded to one Sr(1), one Sr(4), one Ga(1), and one Ga(2) atom to form distorted corner-sharing OSr2Ga2 tetrahedra. In the eighth O site, O(8) is bonded to one Sr(2), one Cr(1), one Cr(3), and one Al(2) atom to form distorted corner-sharing OSrAlCr2 trigonal pyramids. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Sr(4), one Cr(1), one Cr(3), and one Al(1) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Sr(4), two equivalent Sr(2), one Cr(1), and one Ga(1) atom. In the eleventh O site, O(11) is bonded in a 5-coordinate geometry to one Sr(1), two equivalent Sr(3), one Cr(2), and one Ga(1) atom. In the twelfth O site, O(12) is bonded in a 5-coordinate geometry to one Sr(3), two equivalent Sr(1), one Cr(4), and one Ga(2) atom. In the thirteenth O site, O(13) is bonded in a 3-coordinate geometry to one Sr(1), one Sr(3), one Cr(2), one Cr(4), and one Al(2) atom. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(3), one Cr(2), one Cr(4), and one Al(2) atom. is represented by the CIF card [CIF]
data_Sr2AlCr2GaO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.470
_cell_length_b   5.878
_cell_length_c   11.506
_cell_angle_alpha   99.077
_cell_angle_beta   103.162
_cell_angle_gamma   89.926
_symmetry_Int_Tables_number   1
_cell_volume   355.522
_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  0.143  0.219  0.298  1.0
  Sr  Sr1  1  0.826  0.787  0.697  1.0
  Sr  Sr2  1  0.656  0.664  0.296  1.0
  Sr  Sr3  1  0.328  0.345  0.692  1.0
  Al  Al4  1  0.516  0.406  0.992  1.0
  Al  Al5  1  0.977  0.934  0.001  1.0
  Cr  Cr6  1  0.426  0.875  0.879  1.0
  Cr  Cr7  1  0.077  0.628  0.140  1.0
  Cr  Cr8  1  0.939  0.377  0.878  1.0
  Cr  Cr9  1  0.571  0.126  0.145  1.0
  Ga  Ga10  1  0.213  0.825  0.499  1.0
  Ga  Ga11  1  0.715  0.181  0.499  1.0
  O  O12  1  0.819  0.352  0.102  1.0
  O  O13  1  0.869  0.891  0.498  1.0
  O  O14  1  0.371  0.431  0.120  1.0
  O  O15  1  0.842  0.358  0.649  1.0
  O  O16  1  0.764  0.059  0.886  1.0
  O  O17  1  0.276  0.203  0.887  1.0
  O  O18  1  0.368  0.115  0.496  1.0
  O  O19  1  0.100  0.711  0.897  1.0
  O  O20  1  0.605  0.555  0.883  1.0
  O  O21  1  0.343  0.747  0.650  1.0
  O  O22  1  0.204  0.646  0.350  1.0
  O  O23  1  0.710  0.266  0.351  1.0
  O  O24  1  0.792  0.856  0.109  1.0
  O  O25  1  0.252  0.945  0.129  1.0
[/CIF]
.