The crystal structure described by Ba2GaAsSe5 crystallizes in the orthorhombic Pnma space group. Ba(1) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. Ga(1) is bonded in a tetrahedral geometry to one Se(2), one Se(3), and two equivalent Se(1) atoms. As(1) is bonded in a distorted T-shaped geometry to one Se(4) and two equivalent Se(1) atoms. There are four inequivalent Se sites. In the first Se site, Se(4) is bonded to four equivalent Ba(1) and one As(1) atom to form SeBa4As square pyramids that share corners with four equivalent Se(4)Ba4As square pyramids, corners with four equivalent Se(2)Ba4Ga square pyramids, corners with six equivalent Se(1)Ba2GaAs trigonal pyramids, edges with two equivalent Se(2)Ba4Ga square pyramids, edges with four equivalent Se(3)Ba4Ga square pyramids, and edges with two equivalent Se(1)Ba2GaAs trigonal pyramids. In the second Se site, Se(1) is bonded to two equivalent Ba(1), one Ga(1), and one As(1) atom to form distorted SeBa2GaAs trigonal pyramids that share corners with three equivalent Se(4)Ba4As square pyramids, corners with three equivalent Se(2)Ba4Ga square pyramids, corners with three equivalent Se(3)Ba4Ga square pyramids, corners with two equivalent Se(1)Ba2GaAs trigonal pyramids,  an edgeedge with one Se(4)Ba4As square pyramid,  an edgeedge with one Se(2)Ba4Ga square pyramid,  an edgeedge with one Se(3)Ba4Ga square pyramid, and  an edgeedge with one Se(1)Ba2GaAs trigonal pyramid. In the third Se site, Se(2) is bonded to four equivalent Ba(1) and one Ga(1) atom to form distorted SeBa4Ga square pyramids that share corners with four equivalent Se(4)Ba4As square pyramids, corners with four equivalent Se(3)Ba4Ga square pyramids, corners with six equivalent Se(1)Ba2GaAs trigonal pyramids,  an edgeedge with one Se(3)Ba4Ga square pyramid, edges with two equivalent Se(4)Ba4As square pyramids, edges with two equivalent Se(2)Ba4Ga square pyramids, edges with two equivalent Se(1)Ba2GaAs trigonal pyramids, and  a faceface with one Se(3)Ba4Ga square pyramid. In the fourth Se site, Se(3) is bonded to four equivalent Ba(1) and one Ga(1) atom to form distorted SeBa4Ga square pyramids that share corners with four equivalent Se(2)Ba4Ga square pyramids, corners with four equivalent Se(3)Ba4Ga square pyramids, corners with six equivalent Se(1)Ba2GaAs trigonal pyramids,  an edgeedge with one Se(2)Ba4Ga square pyramid, edges with four equivalent Se(4)Ba4As square pyramids, edges with two equivalent Se(1)Ba2GaAs trigonal pyramids, and  a faceface with one Se(2)Ba4Ga square pyramid. is represented by the CIF card [CIF]
data_Ba2GaAsSe5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.145
_cell_length_b   9.389
_cell_length_c   12.800
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1099.011
_cell_formula_units_Z   4
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  0.994  0.132  0.674  1.0
  Ba  Ba1  1  0.506  0.368  0.174  1.0
  Ba  Ba2  1  0.494  0.868  0.326  1.0
  Ba  Ba3  1  0.006  0.632  0.826  1.0
  Ba  Ba4  1  0.006  0.868  0.326  1.0
  Ba  Ba5  1  0.494  0.632  0.826  1.0
  Ba  Ba6  1  0.506  0.132  0.674  1.0
  Ba  Ba7  1  0.994  0.368  0.174  1.0
  Ga  Ga8  1  0.250  0.836  0.597  1.0
  Ga  Ga9  1  0.250  0.664  0.097  1.0
  Ga  Ga10  1  0.750  0.164  0.403  1.0
  Ga  Ga11  1  0.750  0.336  0.903  1.0
  As  As12  1  0.250  0.495  0.536  1.0
  As  As13  1  0.250  0.005  0.036  1.0
  As  As14  1  0.750  0.505  0.464  1.0
  As  As15  1  0.750  0.995  0.964  1.0
  Se  Se16  1  0.047  0.670  0.557  1.0
  Se  Se17  1  0.453  0.830  0.057  1.0
  Se  Se18  1  0.547  0.330  0.443  1.0
  Se  Se19  1  0.953  0.170  0.943  1.0
  Se  Se20  1  0.953  0.330  0.443  1.0
  Se  Se21  1  0.547  0.170  0.943  1.0
  Se  Se22  1  0.453  0.670  0.557  1.0
  Se  Se23  1  0.047  0.830  0.057  1.0
  Se  Se24  1  0.750  0.958  0.512  1.0
  Se  Se25  1  0.750  0.542  0.012  1.0
  Se  Se26  1  0.250  0.042  0.488  1.0
  Se  Se27  1  0.250  0.458  0.988  1.0
  Se  Se28  1  0.250  0.901  0.778  1.0
  Se  Se29  1  0.250  0.599  0.278  1.0
  Se  Se30  1  0.750  0.099  0.222  1.0
  Se  Se31  1  0.750  0.401  0.722  1.0
  Se  Se32  1  0.250  0.398  0.713  1.0
  Se  Se33  1  0.250  0.102  0.213  1.0
  Se  Se34  1  0.750  0.602  0.287  1.0
  Se  Se35  1  0.750  0.898  0.787  1.0
[/CIF]
.
The crystal structure described by Ba2GaAsSe5 crystallizes in the orthorhombic Pnma space group. Ba(1) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. Ga(1) is bonded in a tetrahedral geometry to one Se(2), one Se(3), and two equivalent Se(1) atoms. As(1) is bonded in a distorted T-shaped geometry to one Se(4) and two equivalent Se(1) atoms. There are four inequivalent Se sites. In the first Se site, Se(4) is bonded to four equivalent Ba(1) and one As(1) atom to form SeBa4As square pyramids that share corners with four equivalent Se(4)Ba4As square pyramids, corners with four equivalent Se(2)Ba4Ga square pyramids, corners with six equivalent Se(1)Ba2GaAs trigonal pyramids, edges with two equivalent Se(2)Ba4Ga square pyramids, edges with four equivalent Se(3)Ba4Ga square pyramids, and edges with two equivalent Se(1)Ba2GaAs trigonal pyramids. In the second Se site, Se(1) is bonded to two equivalent Ba(1), one Ga(1), and one As(1) atom to form distorted SeBa2GaAs trigonal pyramids that share corners with three equivalent Se(4)Ba4As square pyramids, corners with three equivalent Se(2)Ba4Ga square pyramids, corners with three equivalent Se(3)Ba4Ga square pyramids, corners with two equivalent Se(1)Ba2GaAs trigonal pyramids,  an edgeedge with one Se(4)Ba4As square pyramid,  an edgeedge with one Se(2)Ba4Ga square pyramid,  an edgeedge with one Se(3)Ba4Ga square pyramid, and  an edgeedge with one Se(1)Ba2GaAs trigonal pyramid. In the third Se site, Se(2) is bonded to four equivalent Ba(1) and one Ga(1) atom to form distorted SeBa4Ga square pyramids that share corners with four equivalent Se(4)Ba4As square pyramids, corners with four equivalent Se(3)Ba4Ga square pyramids, corners with six equivalent Se(1)Ba2GaAs trigonal pyramids,  an edgeedge with one Se(3)Ba4Ga square pyramid, edges with two equivalent Se(4)Ba4As square pyramids, edges with two equivalent Se(2)Ba4Ga square pyramids, edges with two equivalent Se(1)Ba2GaAs trigonal pyramids, and  a faceface with one Se(3)Ba4Ga square pyramid. In the fourth Se site, Se(3) is bonded to four equivalent Ba(1) and one Ga(1) atom to form distorted SeBa4Ga square pyramids that share corners with four equivalent Se(2)Ba4Ga square pyramids, corners with four equivalent Se(3)Ba4Ga square pyramids, corners with six equivalent Se(1)Ba2GaAs trigonal pyramids,  an edgeedge with one Se(2)Ba4Ga square pyramid, edges with four equivalent Se(4)Ba4As square pyramids, edges with two equivalent Se(1)Ba2GaAs trigonal pyramids, and  a faceface with one Se(2)Ba4Ga square pyramid. is represented by the CIF card [CIF]
data_Ba2GaAsSe5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.145
_cell_length_b   9.389
_cell_length_c   12.800
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1099.011
_cell_formula_units_Z   4
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  0.994  0.132  0.674  1.0
  Ba  Ba1  1  0.506  0.368  0.174  1.0
  Ba  Ba2  1  0.494  0.868  0.326  1.0
  Ba  Ba3  1  0.006  0.632  0.826  1.0
  Ba  Ba4  1  0.006  0.868  0.326  1.0
  Ba  Ba5  1  0.494  0.632  0.826  1.0
  Ba  Ba6  1  0.506  0.132  0.674  1.0
  Ba  Ba7  1  0.994  0.368  0.174  1.0
  Ga  Ga8  1  0.250  0.836  0.597  1.0
  Ga  Ga9  1  0.250  0.664  0.097  1.0
  Ga  Ga10  1  0.750  0.164  0.403  1.0
  Ga  Ga11  1  0.750  0.336  0.903  1.0
  As  As12  1  0.250  0.495  0.536  1.0
  As  As13  1  0.250  0.005  0.036  1.0
  As  As14  1  0.750  0.505  0.464  1.0
  As  As15  1  0.750  0.995  0.964  1.0
  Se  Se16  1  0.047  0.670  0.557  1.0
  Se  Se17  1  0.453  0.830  0.057  1.0
  Se  Se18  1  0.547  0.330  0.443  1.0
  Se  Se19  1  0.953  0.170  0.943  1.0
  Se  Se20  1  0.953  0.330  0.443  1.0
  Se  Se21  1  0.547  0.170  0.943  1.0
  Se  Se22  1  0.453  0.670  0.557  1.0
  Se  Se23  1  0.047  0.830  0.057  1.0
  Se  Se24  1  0.750  0.958  0.512  1.0
  Se  Se25  1  0.750  0.542  0.012  1.0
  Se  Se26  1  0.250  0.042  0.488  1.0
  Se  Se27  1  0.250  0.458  0.988  1.0
  Se  Se28  1  0.250  0.901  0.778  1.0
  Se  Se29  1  0.250  0.599  0.278  1.0
  Se  Se30  1  0.750  0.099  0.222  1.0
  Se  Se31  1  0.750  0.401  0.722  1.0
  Se  Se32  1  0.250  0.398  0.713  1.0
  Se  Se33  1  0.250  0.102  0.213  1.0
  Se  Se34  1  0.750  0.602  0.287  1.0
  Se  Se35  1  0.750  0.898  0.787  1.0
[/CIF]
.