The material structure described by Sr2Ti2GaAlO7 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(14), one O(3), one O(7), two equivalent O(11), and two equivalent O(12) atoms. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one O(2), one O(6), one O(8), two equivalent O(10), and two equivalent O(4) atoms. In the third Sr site, Sr(3) is bonded in a 8-coordinate geometry to one O(13), one O(14), one O(2), one O(3), two equivalent O(11), and two equivalent O(12) atoms. In the fourth Sr site, Sr(4) is bonded in a 7-coordinate geometry to one O(6), one O(7), one O(8), two equivalent O(10), and two equivalent O(4) atoms. There are four inequivalent Ti sites. In the first Ti site, Ti(1) is bonded in a 4-coordinate geometry to one O(5), one O(6), one O(8), and one O(9) atom. In the second Ti site, Ti(2) is bonded in a 4-coordinate geometry to one O(1), one O(13), one O(14), and one O(3) atom. In the third Ti site, Ti(3) is bonded in a 4-coordinate geometry to one O(5), one O(6), one O(8), and one O(9) atom. In the fourth Ti site, Ti(4) is bonded in a 4-coordinate geometry to one O(1), one O(13), one O(14), and one O(3) atom. 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 corner-sharing GaO4 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 corner-sharing GaO4 tetrahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a distorted T-shaped geometry to one O(13), one O(5), and one O(9) atom. In the second Al site, Al(2) is bonded in a distorted T-shaped geometry to one O(1), one O(5), and one O(9) atom. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Sr(1), one Ti(2), one Ti(4), and one Al(2) 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  a cornercorner with one O(8)Sr2Ti2 tetrahedra and corners with two equivalent O(7)Sr2Ga2 tetrahedra. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(3), one Ti(2), and one Ti(4) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to two equivalent Sr(2), two equivalent Sr(4), and one Ga(2) atom. In the fifth O site, O(5) is bonded in a see-saw-like geometry to one Ti(1), one Ti(3), one Al(1), and one Al(2) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Sr(2), one Sr(4), one Ti(1), and one Ti(3) 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 OSr2Ga2 tetrahedra that share  a cornercorner with one O(8)Sr2Ti2 tetrahedra and corners with two equivalent O(2)Sr2Ga2 tetrahedra. In the eighth O site, O(8) is bonded to one Sr(2), one Sr(4), one Ti(1), and one Ti(3) atom to form distorted corner-sharing OSr2Ti2 tetrahedra. In the ninth O site, O(9) is bonded in a see-saw-like geometry to one Ti(1), one Ti(3), one Al(1), and one Al(2) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to two equivalent Sr(2), two equivalent Sr(4), and one Ga(1) atom. In the eleventh O site, O(11) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(3), and one Ga(1) atom. In the twelfth O site, O(12) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(3), and one Ga(2) atom. In the thirteenth O site, O(13) is bonded in a 3-coordinate geometry to one Sr(3), one Ti(2), one Ti(4), and one Al(1) atom. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(3), one Ti(2), and one Ti(4) atom. is represented by the CIF file [CIF]
data_Sr2Ti2AlGaO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.161
_cell_length_b   5.334
_cell_length_c   13.624
_cell_angle_alpha   100.507
_cell_angle_beta   100.788
_cell_angle_gamma   90.245
_symmetry_Int_Tables_number   1
_cell_volume   361.956
_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  0.149  0.139  0.316  1.0
  Sr  Sr1  1  0.826  0.834  0.676  1.0
  Sr  Sr2  1  0.660  0.664  0.318  1.0
  Sr  Sr3  1  0.345  0.308  0.674  1.0
  Ti  Ti4  1  0.518  0.931  0.896  1.0
  Ti  Ti5  1  0.993  0.570  0.112  1.0
  Ti  Ti6  1  0.861  0.428  0.896  1.0
  Ti  Ti7  1  0.605  0.074  0.113  1.0
  Al  Al8  1  0.411  0.470  0.987  1.0
  Al  Al9  1  0.079  0.988  0.995  1.0
  Ga  Ga10  1  0.294  0.670  0.496  1.0
  Ga  Ga11  1  0.796  0.307  0.497  1.0
  O  O12  1  0.258  0.918  0.115  1.0
  O  O13  1  0.667  0.644  0.500  1.0
  O  O14  1  0.801  0.841  0.175  1.0
  O  O15  1  0.808  0.272  0.632  1.0
  O  O16  1  0.199  0.690  0.915  1.0
  O  O17  1  0.652  0.641  0.822  1.0
  O  O18  1  0.167  0.333  0.496  1.0
  O  O19  1  0.653  0.140  0.820  1.0
  O  O20  1  0.195  0.184  0.906  1.0
  O  O21  1  0.288  0.828  0.630  1.0
  O  O22  1  0.172  0.706  0.363  1.0
  O  O23  1  0.657  0.149  0.365  1.0
  O  O24  1  0.331  0.406  0.104  1.0
  O  O25  1  0.858  0.347  0.180  1.0
[/CIF]
.
The material structure described by Sr2Ti2GaAlO7 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(14), one O(3), one O(7), two equivalent O(11), and two equivalent O(12) atoms. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one O(2), one O(6), one O(8), two equivalent O(10), and two equivalent O(4) atoms. In the third Sr site, Sr(3) is bonded in a 8-coordinate geometry to one O(13), one O(14), one O(2), one O(3), two equivalent O(11), and two equivalent O(12) atoms. In the fourth Sr site, Sr(4) is bonded in a 7-coordinate geometry to one O(6), one O(7), one O(8), two equivalent O(10), and two equivalent O(4) atoms. There are four inequivalent Ti sites. In the first Ti site, Ti(1) is bonded in a 4-coordinate geometry to one O(5), one O(6), one O(8), and one O(9) atom. In the second Ti site, Ti(2) is bonded in a 4-coordinate geometry to one O(1), one O(13), one O(14), and one O(3) atom. In the third Ti site, Ti(3) is bonded in a 4-coordinate geometry to one O(5), one O(6), one O(8), and one O(9) atom. In the fourth Ti site, Ti(4) is bonded in a 4-coordinate geometry to one O(1), one O(13), one O(14), and one O(3) atom. 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 corner-sharing GaO4 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 corner-sharing GaO4 tetrahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a distorted T-shaped geometry to one O(13), one O(5), and one O(9) atom. In the second Al site, Al(2) is bonded in a distorted T-shaped geometry to one O(1), one O(5), and one O(9) atom. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Sr(1), one Ti(2), one Ti(4), and one Al(2) 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  a cornercorner with one O(8)Sr2Ti2 tetrahedra and corners with two equivalent O(7)Sr2Ga2 tetrahedra. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(3), one Ti(2), and one Ti(4) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to two equivalent Sr(2), two equivalent Sr(4), and one Ga(2) atom. In the fifth O site, O(5) is bonded in a see-saw-like geometry to one Ti(1), one Ti(3), one Al(1), and one Al(2) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Sr(2), one Sr(4), one Ti(1), and one Ti(3) 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 OSr2Ga2 tetrahedra that share  a cornercorner with one O(8)Sr2Ti2 tetrahedra and corners with two equivalent O(2)Sr2Ga2 tetrahedra. In the eighth O site, O(8) is bonded to one Sr(2), one Sr(4), one Ti(1), and one Ti(3) atom to form distorted corner-sharing OSr2Ti2 tetrahedra. In the ninth O site, O(9) is bonded in a see-saw-like geometry to one Ti(1), one Ti(3), one Al(1), and one Al(2) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to two equivalent Sr(2), two equivalent Sr(4), and one Ga(1) atom. In the eleventh O site, O(11) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(3), and one Ga(1) atom. In the twelfth O site, O(12) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(3), and one Ga(2) atom. In the thirteenth O site, O(13) is bonded in a 3-coordinate geometry to one Sr(3), one Ti(2), one Ti(4), and one Al(1) atom. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(3), one Ti(2), and one Ti(4) atom. is represented by the CIF file [CIF]
data_Sr2Ti2AlGaO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.161
_cell_length_b   5.334
_cell_length_c   13.624
_cell_angle_alpha   100.507
_cell_angle_beta   100.788
_cell_angle_gamma   90.245
_symmetry_Int_Tables_number   1
_cell_volume   361.956
_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  0.149  0.139  0.316  1.0
  Sr  Sr1  1  0.826  0.834  0.676  1.0
  Sr  Sr2  1  0.660  0.664  0.318  1.0
  Sr  Sr3  1  0.345  0.308  0.674  1.0
  Ti  Ti4  1  0.518  0.931  0.896  1.0
  Ti  Ti5  1  0.993  0.570  0.112  1.0
  Ti  Ti6  1  0.861  0.428  0.896  1.0
  Ti  Ti7  1  0.605  0.074  0.113  1.0
  Al  Al8  1  0.411  0.470  0.987  1.0
  Al  Al9  1  0.079  0.988  0.995  1.0
  Ga  Ga10  1  0.294  0.670  0.496  1.0
  Ga  Ga11  1  0.796  0.307  0.497  1.0
  O  O12  1  0.258  0.918  0.115  1.0
  O  O13  1  0.667  0.644  0.500  1.0
  O  O14  1  0.801  0.841  0.175  1.0
  O  O15  1  0.808  0.272  0.632  1.0
  O  O16  1  0.199  0.690  0.915  1.0
  O  O17  1  0.652  0.641  0.822  1.0
  O  O18  1  0.167  0.333  0.496  1.0
  O  O19  1  0.653  0.140  0.820  1.0
  O  O20  1  0.195  0.184  0.906  1.0
  O  O21  1  0.288  0.828  0.630  1.0
  O  O22  1  0.172  0.706  0.363  1.0
  O  O23  1  0.657  0.149  0.365  1.0
  O  O24  1  0.331  0.406  0.104  1.0
  O  O25  1  0.858  0.347  0.180  1.0
[/CIF]
.