The compound described by BaAl4Se7 crystallizes in the monoclinic Pc space group. Ba(1) is bonded in a 6-coordinate geometry to one Se(2), one Se(3), one Se(5), one Se(6), and two equivalent Se(1) atoms. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded to one Se(1), one Se(4), one Se(5), and one Se(7) atom to form corner-sharing AlSe4 tetrahedra. In the second Al site, Al(2) is bonded to one Se(1), one Se(2), one Se(3), and one Se(7) atom to form corner-sharing AlSe4 tetrahedra. In the third Al site, Al(3) is bonded to one Se(3), one Se(4), one Se(6), and one Se(7) atom to form corner-sharing AlSe4 tetrahedra. In the fourth Al site, Al(4) is bonded to one Se(2), one Se(4), one Se(5), and one Se(6) atom to form corner-sharing AlSe4 tetrahedra. There are seven inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted water-like geometry to two equivalent Ba(1), one Al(1), and one Al(2) atom. In the second Se site, Se(2) is bonded in a 3-coordinate geometry to one Ba(1), one Al(2), and one Al(4) atom. In the third Se site, Se(3) is bonded in a distorted water-like geometry to one Ba(1), one Al(2), and one Al(3) atom. In the fourth Se site, Se(4) is bonded in a trigonal non-coplanar geometry to one Al(1), one Al(3), and one Al(4) atom. In the fifth Se site, Se(5) is bonded in a distorted water-like geometry to one Ba(1), one Al(1), and one Al(4) atom. In the sixth Se site, Se(6) is bonded in a distorted water-like geometry to one Ba(1), one Al(3), and one Al(4) atom. In the seventh Se site, Se(7) is bonded in a trigonal non-coplanar geometry to one Al(1), one Al(2), and one Al(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaAl4Se7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.579
_cell_length_b   7.685
_cell_length_c   14.816
_cell_angle_alpha   58.938
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   641.701
_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  0.642  0.435  0.546  1.0
  Ba  Ba1  1  0.358  0.435  0.046  1.0
  Al  Al2  1  0.840  0.992  0.241  1.0
  Al  Al3  1  0.160  0.992  0.741  1.0
  Al  Al4  1  0.986  0.998  0.503  1.0
  Al  Al5  1  0.014  0.998  0.003  1.0
  Al  Al6  1  0.847  0.508  0.228  1.0
  Al  Al7  1  0.153  0.508  0.728  1.0
  Al  Al8  1  0.634  0.764  0.725  1.0
  Al  Al9  1  0.366  0.764  0.225  1.0
  Se  Se10  1  0.855  0.209  0.057  1.0
  Se  Se11  1  0.145  0.209  0.557  1.0
  Se  Se12  1  0.637  0.991  0.541  1.0
  Se  Se13  1  0.363  0.991  0.041  1.0
  Se  Se14  1  0.897  0.673  0.046  1.0
  Se  Se15  1  0.103  0.673  0.546  1.0
  Se  Se16  1  0.976  0.675  0.806  1.0
  Se  Se17  1  0.024  0.675  0.306  1.0
  Se  Se18  1  0.485  0.904  0.819  1.0
  Se  Se19  1  0.515  0.904  0.319  1.0
  Se  Se20  1  0.497  0.440  0.778  1.0
  Se  Se21  1  0.503  0.440  0.278  1.0
  Se  Se22  1  0.979  0.180  0.808  1.0
  Se  Se23  1  0.021  0.180  0.308  1.0
[/CIF]
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The compound described by BaAl4Se7 crystallizes in the monoclinic Pc space group. Ba(1) is bonded in a 6-coordinate geometry to one Se(2), one Se(3), one Se(5), one Se(6), and two equivalent Se(1) atoms. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded to one Se(1), one Se(4), one Se(5), and one Se(7) atom to form corner-sharing AlSe4 tetrahedra. In the second Al site, Al(2) is bonded to one Se(1), one Se(2), one Se(3), and one Se(7) atom to form corner-sharing AlSe4 tetrahedra. In the third Al site, Al(3) is bonded to one Se(3), one Se(4), one Se(6), and one Se(7) atom to form corner-sharing AlSe4 tetrahedra. In the fourth Al site, Al(4) is bonded to one Se(2), one Se(4), one Se(5), and one Se(6) atom to form corner-sharing AlSe4 tetrahedra. There are seven inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted water-like geometry to two equivalent Ba(1), one Al(1), and one Al(2) atom. In the second Se site, Se(2) is bonded in a 3-coordinate geometry to one Ba(1), one Al(2), and one Al(4) atom. In the third Se site, Se(3) is bonded in a distorted water-like geometry to one Ba(1), one Al(2), and one Al(3) atom. In the fourth Se site, Se(4) is bonded in a trigonal non-coplanar geometry to one Al(1), one Al(3), and one Al(4) atom. In the fifth Se site, Se(5) is bonded in a distorted water-like geometry to one Ba(1), one Al(1), and one Al(4) atom. In the sixth Se site, Se(6) is bonded in a distorted water-like geometry to one Ba(1), one Al(3), and one Al(4) atom. In the seventh Se site, Se(7) is bonded in a trigonal non-coplanar geometry to one Al(1), one Al(2), and one Al(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaAl4Se7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.579
_cell_length_b   7.685
_cell_length_c   14.816
_cell_angle_alpha   58.938
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   641.701
_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  0.642  0.435  0.546  1.0
  Ba  Ba1  1  0.358  0.435  0.046  1.0
  Al  Al2  1  0.840  0.992  0.241  1.0
  Al  Al3  1  0.160  0.992  0.741  1.0
  Al  Al4  1  0.986  0.998  0.503  1.0
  Al  Al5  1  0.014  0.998  0.003  1.0
  Al  Al6  1  0.847  0.508  0.228  1.0
  Al  Al7  1  0.153  0.508  0.728  1.0
  Al  Al8  1  0.634  0.764  0.725  1.0
  Al  Al9  1  0.366  0.764  0.225  1.0
  Se  Se10  1  0.855  0.209  0.057  1.0
  Se  Se11  1  0.145  0.209  0.557  1.0
  Se  Se12  1  0.637  0.991  0.541  1.0
  Se  Se13  1  0.363  0.991  0.041  1.0
  Se  Se14  1  0.897  0.673  0.046  1.0
  Se  Se15  1  0.103  0.673  0.546  1.0
  Se  Se16  1  0.976  0.675  0.806  1.0
  Se  Se17  1  0.024  0.675  0.306  1.0
  Se  Se18  1  0.485  0.904  0.819  1.0
  Se  Se19  1  0.515  0.904  0.319  1.0
  Se  Se20  1  0.497  0.440  0.778  1.0
  Se  Se21  1  0.503  0.440  0.278  1.0
  Se  Se22  1  0.979  0.180  0.808  1.0
  Se  Se23  1  0.021  0.180  0.308  1.0
[/CIF]
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