The material described by Ba2GdGaSe5 crystallizes in the triclinic P-1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 8-coordinate geometry to one Se(1), one Se(4), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(5) atoms. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one Se(2), one Se(3), two equivalent Se(1), two equivalent Se(4), and two equivalent Se(5) atoms. Gd(1) is bonded to one Se(1), one Se(2), two equivalent Se(3), and two equivalent Se(4) atoms to form GdSe6 octahedra that share edges with two equivalent Gd(1)Se6 octahedra and edges with two equivalent Ga(1)Se4 tetrahedra. Ga(1) is bonded to one Se(1), one Se(2), one Se(3), and one Se(5) atom to form GaSe4 tetrahedra that share edges with two equivalent Gd(1)Se6 octahedra. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded to one Ba(1), two equivalent Ba(2), one Gd(1), and one Ga(1) atom to form distorted SeBa3GdGa trigonal bipyramids that share  a cornercorner with one Se(3)Ba3Gd2Ga octahedra, corners with three equivalent Se(5)Ba4Ga square pyramids, corners with five equivalent Se(4)Ba3Gd2 trigonal bipyramids, edges with three equivalent Se(3)Ba3Gd2Ga octahedra, edges with two equivalent Se(5)Ba4Ga square pyramids,  an edgeedge with one Se(4)Ba3Gd2 trigonal bipyramid, and  an edgeedge with one Se(1)Ba3GdGa trigonal bipyramid. The corner-sharing octahedral tilt angles are 44°. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to one Ba(2), two equivalent Ba(1), one Gd(1), and one Ga(1) atom. In the third Se site, Se(3) is bonded to one Ba(2), two equivalent Ba(1), two equivalent Gd(1), and one Ga(1) atom to form distorted SeBa3Gd2Ga octahedra that share corners with four equivalent Se(5)Ba4Ga square pyramids,  a cornercorner with one Se(1)Ba3GdGa trigonal bipyramid, corners with two equivalent Se(4)Ba3Gd2 trigonal bipyramids, edges with two equivalent Se(3)Ba3Gd2Ga octahedra, edges with three equivalent Se(4)Ba3Gd2 trigonal bipyramids, edges with three equivalent Se(1)Ba3GdGa trigonal bipyramids, and  a faceface with one Se(5)Ba4Ga square pyramid. In the fourth Se site, Se(4) is bonded to one Ba(1), two equivalent Ba(2), and two equivalent Gd(1) atoms to form distorted SeBa3Gd2 trigonal bipyramids that share corners with two equivalent Se(3)Ba3Gd2Ga octahedra, corners with four equivalent Se(5)Ba4Ga square pyramids, corners with five equivalent Se(1)Ba3GdGa trigonal bipyramids, edges with three equivalent Se(3)Ba3Gd2Ga octahedra,  an edgeedge with one Se(5)Ba4Ga square pyramid,  an edgeedge with one Se(1)Ba3GdGa trigonal bipyramid, and edges with two equivalent Se(4)Ba3Gd2 trigonal bipyramids. The corner-sharing octahedral tilt angles are 6°. In the fifth Se site, Se(5) is bonded to two equivalent Ba(1), two equivalent Ba(2), and one Ga(1) atom to form SeBa4Ga square pyramids that share corners with four equivalent Se(3)Ba3Gd2Ga octahedra, corners with three equivalent Se(1)Ba3GdGa trigonal bipyramids, corners with four equivalent Se(4)Ba3Gd2 trigonal bipyramids, edges with two equivalent Se(5)Ba4Ga square pyramids,  an edgeedge with one Se(4)Ba3Gd2 trigonal bipyramid, edges with two equivalent Se(1)Ba3GdGa trigonal bipyramids, and  a faceface with one Se(3)Ba3Gd2Ga octahedra. The corner-sharing octahedral tilt angles range from 45-67°. is represented by the CIF file [CIF]
data_Ba2GdGaSe5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.407
_cell_length_b   8.822
_cell_length_c   9.561
_cell_angle_alpha   103.627
_cell_angle_beta   103.082
_cell_angle_gamma   107.473
_symmetry_Int_Tables_number   1
_cell_volume   548.589
_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
  Ba  Ba0  1  0.634  0.978  0.291  1.0
  Ba  Ba1  1  0.366  0.022  0.709  1.0
  Ba  Ba2  1  0.342  0.510  0.706  1.0
  Ba  Ba3  1  0.658  0.490  0.294  1.0
  Gd  Gd4  1  0.998  0.731  0.998  1.0
  Gd  Gd5  1  0.002  0.269  0.002  1.0
  Ga  Ga6  1  0.805  0.871  0.687  1.0
  Ga  Ga7  1  0.195  0.129  0.313  1.0
  Se  Se8  1  0.988  0.684  0.683  1.0
  Se  Se9  1  0.012  0.316  0.317  1.0
  Se  Se10  1  0.983  0.152  0.686  1.0
  Se  Se11  1  0.017  0.848  0.314  1.0
  Se  Se12  1  0.710  0.908  0.925  1.0
  Se  Se13  1  0.290  0.092  0.075  1.0
  Se  Se14  1  0.705  0.410  0.945  1.0
  Se  Se15  1  0.295  0.590  0.055  1.0
  Se  Se16  1  0.488  0.741  0.492  1.0
  Se  Se17  1  0.512  0.259  0.508  1.0
[/CIF]
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The material described by Ba2GdGaSe5 crystallizes in the triclinic P-1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 8-coordinate geometry to one Se(1), one Se(4), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(5) atoms. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one Se(2), one Se(3), two equivalent Se(1), two equivalent Se(4), and two equivalent Se(5) atoms. Gd(1) is bonded to one Se(1), one Se(2), two equivalent Se(3), and two equivalent Se(4) atoms to form GdSe6 octahedra that share edges with two equivalent Gd(1)Se6 octahedra and edges with two equivalent Ga(1)Se4 tetrahedra. Ga(1) is bonded to one Se(1), one Se(2), one Se(3), and one Se(5) atom to form GaSe4 tetrahedra that share edges with two equivalent Gd(1)Se6 octahedra. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded to one Ba(1), two equivalent Ba(2), one Gd(1), and one Ga(1) atom to form distorted SeBa3GdGa trigonal bipyramids that share  a cornercorner with one Se(3)Ba3Gd2Ga octahedra, corners with three equivalent Se(5)Ba4Ga square pyramids, corners with five equivalent Se(4)Ba3Gd2 trigonal bipyramids, edges with three equivalent Se(3)Ba3Gd2Ga octahedra, edges with two equivalent Se(5)Ba4Ga square pyramids,  an edgeedge with one Se(4)Ba3Gd2 trigonal bipyramid, and  an edgeedge with one Se(1)Ba3GdGa trigonal bipyramid. The corner-sharing octahedral tilt angles are 44°. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to one Ba(2), two equivalent Ba(1), one Gd(1), and one Ga(1) atom. In the third Se site, Se(3) is bonded to one Ba(2), two equivalent Ba(1), two equivalent Gd(1), and one Ga(1) atom to form distorted SeBa3Gd2Ga octahedra that share corners with four equivalent Se(5)Ba4Ga square pyramids,  a cornercorner with one Se(1)Ba3GdGa trigonal bipyramid, corners with two equivalent Se(4)Ba3Gd2 trigonal bipyramids, edges with two equivalent Se(3)Ba3Gd2Ga octahedra, edges with three equivalent Se(4)Ba3Gd2 trigonal bipyramids, edges with three equivalent Se(1)Ba3GdGa trigonal bipyramids, and  a faceface with one Se(5)Ba4Ga square pyramid. In the fourth Se site, Se(4) is bonded to one Ba(1), two equivalent Ba(2), and two equivalent Gd(1) atoms to form distorted SeBa3Gd2 trigonal bipyramids that share corners with two equivalent Se(3)Ba3Gd2Ga octahedra, corners with four equivalent Se(5)Ba4Ga square pyramids, corners with five equivalent Se(1)Ba3GdGa trigonal bipyramids, edges with three equivalent Se(3)Ba3Gd2Ga octahedra,  an edgeedge with one Se(5)Ba4Ga square pyramid,  an edgeedge with one Se(1)Ba3GdGa trigonal bipyramid, and edges with two equivalent Se(4)Ba3Gd2 trigonal bipyramids. The corner-sharing octahedral tilt angles are 6°. In the fifth Se site, Se(5) is bonded to two equivalent Ba(1), two equivalent Ba(2), and one Ga(1) atom to form SeBa4Ga square pyramids that share corners with four equivalent Se(3)Ba3Gd2Ga octahedra, corners with three equivalent Se(1)Ba3GdGa trigonal bipyramids, corners with four equivalent Se(4)Ba3Gd2 trigonal bipyramids, edges with two equivalent Se(5)Ba4Ga square pyramids,  an edgeedge with one Se(4)Ba3Gd2 trigonal bipyramid, edges with two equivalent Se(1)Ba3GdGa trigonal bipyramids, and  a faceface with one Se(3)Ba3Gd2Ga octahedra. The corner-sharing octahedral tilt angles range from 45-67°. is represented by the CIF file [CIF]
data_Ba2GdGaSe5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.407
_cell_length_b   8.822
_cell_length_c   9.561
_cell_angle_alpha   103.627
_cell_angle_beta   103.082
_cell_angle_gamma   107.473
_symmetry_Int_Tables_number   1
_cell_volume   548.589
_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
  Ba  Ba0  1  0.634  0.978  0.291  1.0
  Ba  Ba1  1  0.366  0.022  0.709  1.0
  Ba  Ba2  1  0.342  0.510  0.706  1.0
  Ba  Ba3  1  0.658  0.490  0.294  1.0
  Gd  Gd4  1  0.998  0.731  0.998  1.0
  Gd  Gd5  1  0.002  0.269  0.002  1.0
  Ga  Ga6  1  0.805  0.871  0.687  1.0
  Ga  Ga7  1  0.195  0.129  0.313  1.0
  Se  Se8  1  0.988  0.684  0.683  1.0
  Se  Se9  1  0.012  0.316  0.317  1.0
  Se  Se10  1  0.983  0.152  0.686  1.0
  Se  Se11  1  0.017  0.848  0.314  1.0
  Se  Se12  1  0.710  0.908  0.925  1.0
  Se  Se13  1  0.290  0.092  0.075  1.0
  Se  Se14  1  0.705  0.410  0.945  1.0
  Se  Se15  1  0.295  0.590  0.055  1.0
  Se  Se16  1  0.488  0.741  0.492  1.0
  Se  Se17  1  0.512  0.259  0.508  1.0
[/CIF]
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